Articles Archive – Feline

January 7, 2026 

Objective

To highlight clinical and clinicopathologic differences between kittens with feline infectious peritonitis–associated uveitis (FIP-AU) versus those with an otherwise similar feline undifferentiated resolving uveitis (FURU).

Methods

Clinical and clinicopathologic data were compared between 22 kittens with FURU and 8 with necropsy-confirmed FIP-AU examined between January 1, 1985, and December 31, 2022.

Results

Sex, lifestyle, seasonality, household cat numbers and systemic signs were similar in both groups. Feline undifferentiated resolving uveitis occurred predominantly in domestic-breed kittens from shelters, whereas FIP-AU was more frequent in purebred or stray cats. Duration of ocular signs before presentation was 1 to 2 weeks for FURU versus > 2 months for FIP-AU. Feline undifferentiated resolving uveitis was more commonly associated with episcleral hyperemia while FIP-AU was more commonly associated with corneal edema, dyscoria, rubeosis iridis, iridal congestion/thickening, posterior synechia, or keratic precipitates. Corneal edema and chemosis were more severe in FIP-AU. No eyes with FURU had fundic abnormalities whereas 6 of 11 eyes with FIP-AU had chorioretinitis. All kittens with FIP-AU presented bilaterally whereas 5 of 15 kittens in which FURU was ultimately bilateral, initially presented unilaterally. Hyperproteinemia, hyperglobulinemia, and hyperbilirubinemia occurred only with FIP-AU. Neither likelihood of a positive coronavirus titer nor titer magnitude differed between groups.

Conclusions

Kittens can develop bilateral fibrinous uveitis with keratic precipitates, systemic signs of illness, and serum coronavirus antibodies which resolves without sequelae following empirical treatment. Syndromic assessment—including careful fundic examination—can help differentiate FURU from FIP-AU and should precede antiviral therapy.

Clinical Relevance

Resolution of uveitis during antiviral treatment does not confirm FIP. Comprehensive diagnostic evaluation is essential to avoid misdiagnosis and inappropriate treatment.

Keywords: ocular; pediatric; disease resolution; inflammatory; idiopathic

Introduction

Uveitis is inflammation of the iris, ciliary body or choroid in various combinations with clinical signs such as blepharospasm; episcleral hyperemia (or “injection”); conjunctival hyperemia; corneal edema; aqueous flare, anterior chamber fibrin or cell, hyphema, hypopyon or keratic precipitates; iris thickening or color change; miosis; decreased intraocular pressure; chorioretinal edema, hemorrhage, or exudation; retinal detachment; or decreased vision.¹ Classically, uveitis in cats has been categorized as exogenous or endogenous, with exogenous uveitis typically secondary to trauma, corneal ulcers, or lens luxation. Causes of endogenous uveitis include bacterial, fungal, viral, or protozoal infection, neoplasia, or immune-mediated disease; however, a cause is frequently not found, even with extensive diagnostic testing, and such cases may become chronic or recurrent.¹ Such cases are typically called “idiopathic” but in human medicine as many as 30% of these may have a definable cause with further testing.² As a result, some have suggested that “idiopathic” be reserved for cases in which no cause is found after thorough diagnostic testing, and that the term “undifferentiated” be used for cases in which testing is limited or in which a pragmatic “response to therapy” approach is taken,³ as is often the case in veterinary medicine. Difficulty clinically differentiating cases ultimately determined to be idiopathic from those in which a cause is found constrains management of affected cats,^4,5 especially where a potentially treatable, communicable, or fatal cause is possible, and management decisions appropriate to that cause are required. Therefore, some generalizations have gained popularity. For example, densely fibrinous or granulomatous uveitis, especially with keratic precipitates, is sometimes considered characteristic of feline infectious peritonitis–associated uveitis (FIP-AU),⁶ and may lead to discussions of euthanasia or administration of antiviral drugs that may be expensive or not legally available within all countries, and which carry the risk of adverse effects. Management decisions such as these would be inappropriate if the disease were, instead, self-limiting or due to an alternate but treatable cause. We identified a group of kittens with severe, fibrinous/granulomatous uveitis extremely similar to FIP-AU but which resolved completely without antiviral therapy specific for coronaviruses (called here feline undifferentiated resolving uveitis [FURU]). The purpose of this retrospective study is to present clinical characteristics, clinicopathologic data, and outcome of kittens ≤ 1 year of age with FURU, and to compare these with kittens with uveitis in which FIP was immunohistochemically confirmed at necropsy. Our hypothesis was that, despite broadly similar clinical presentations, certain historical, clinical, or clinicopathologic features may aid differentiation of these 2 critically different disease syndromes.

Methods

Two populations of kittens were retrospectively identified and reviewed through a digital search of electronic medical records (EMR) from the University of California-Davis Veterinary Medical Teaching Hospital between January 1, 1985, and December 31, 2022. Kittens in the study population (ie, with FURU) were ≤ 1 year of age at initial diagnosis; had been examined at least twice within the study period by a board-certified veterinary ophthalmologist or resident in training using slit lamp biomicroscopy; and had uveitis which resolved without antiviral drugs with known efficacy against coronavirus. To identify kittens with anterior uveitis, panuveitis, and/or chorioretinitis, all 3 of those terms plus “*uceitis,” “*uv*t*,” “*veitis,” and “*ch*r*tis” (to capture misspelled terms) were searched. Records were then reviewed to identify kittens in which no recognized cause was identified. The extent of investigation varied widely from a physical examination only through to extensive serologic testing and body cavity imaging. Specifically, uveitis believed or known to be secondary to trauma, glaucoma, corneal ulceration, keratoconjunctivitis, known infectious agents, lens subluxation/luxation, ocular neoplasia, or following ophthalmic surgery were excluded. Resolution was defined as lack of all clinical signs suggestive of uveitis at the most recent visit, and/or a clinical diagnosis within the EMR of “resolved” or “historic” uveitis while no longer on anti-inflammatory therapy, and/or telephone/email contact with the client at least 4 years after the final visit with no evidence of ocular disease or disease attributable to FIP in that interval. A reference population comprising kittens with uveitis and FIP confirmed immunohistochemically at a necropsy performed at the University of California-Davis Veterinary Medical Teaching Hospital was identified using the search terms “FIP,” “feline infectious peritonitis,” “eye’,” and “uveitis.” For inclusion in the reference population, kittens were required to be ≤ 1 year of age at initial diagnosis; have been examined at least once within the study period by a board-certified veterinary ophthalmologist or resident in training using slit lamp biomicroscopy; have a clinical diagnosis of anterior uveitis, panuveitis, and/or chorioretinitis; and have a histopathological diagnosis consistent with FIP (ie, pyogranulomatous inflammation affecting multiple organs) made at necropsy by a board-certified veterinary pathologist and confirmed with immunohistochemistry in an affected tissue (not necessarily the eye). One kitten with FIP-AU received GS-441524, a nucleoside analog drug, after the initial presentation at which uveitis was diagnosed according to entry criteria. This kitten contributed data to the present study from the period prior to treatment only. For all kittens from both study populations, the EMR was individually reviewed by 2 authors (HS and DJM) to ensure all entry criteria were met and the following data were extracted: signalment, origin, history, lifestyle, ophthalmic examination findings, diagnostic test results, treatment, duration of follow-up, and outcome. For lifestyle, kittens defined as “indoor” could have controlled outdoor access such as enclosed patios and leash walks. Origin of kittens was defined as “breeder” when obtained from a person who breeds cats, “shelter” when obtained from an animal shelter or rescue organization, or “stray” when found or adopted from a person not associated with an animal shelter or rescue group. For kittens with FIP-AU, age at death/euthanasia was recorded, and duration of uveitis was calculated as the period from first ocular signs (as reported by the owner) until death/euthanasia. When duration of ocular signs prior to initial presentation was reported as a range, the longest duration from onset was used for analyses. For both study populations, severity of ocular discharge, conjunctival hyperemia, episcleral hyperemia, chemosis, and corneal edema were individually graded by the examining clinician as absent (0), trace/subtle (0.5), mild (1), mild-to-moderate (1.5), moderate (2), moderate-to-severe (2.5), or severe (3). Aqueous flare, anterior chamber cell, and vitreous cell were graded by the examining clinician as trace (0.5) or 1 through 4 based on a published scale that is used consistently at this institution.^7,8 Where clinicians graded flare or cell as a range, the higher end of that range was used for analyses. Uveitis was consistently defined as “inactive/resolved” (if no signs of uveitis were described, and/or the examining clinician described it this way, and the patient was on no anti-inflammatory drugs), “resolving/improving/medically controlled” (if signs of uveitis were reduced from the prior examination, and/or the examining clinician described it this way), or “active” (if signs of uveitis were unchanged from the prior examination, and/or the examining clinician described it this way).

Statistical analysis

Since uveitis was seen unilaterally or bilaterally (and, when bilaterally, the onset was sometimes asynchronous), data were compared at the kitten or eye level as appropriate. Data were statistically compared between FURU and FIP-AU populations using the Mann-Whitney rank sum, Fisher exact, or Fisher-Freeman-Halton tests as shown. For all analyses, a P value ≤ .05 was considered significant.

Results

Signalment and history

In all, 22 kittens (11 spayed females, 2 intact females, 8 castrated males, and 1 intact male) were diagnosed with FURU. Within the same period, 325 kittens in the same age group were diagnosed with uveitis of any type, therefore, FURU represented 6.7% of all uveitis diagnoses in kittens during this time. Of those 22 kittens, there were 16 domestic shorthair, 2 domestic medium hair, 1 domestic longhair, 1 Maine Coon cross, 1 Siamese, and 1 Bengal. Two kittens were littermates and lived in the same household; all others were from separate homes and presumed unrelated. Uveitis was diagnosed in every month except July with no obvious seasonality observed. Duration of ocular signs prior to initial presentation was about 1 to 2 weeks (Supplementary Table S1). Clinical abnormalities commonly reported by caregivers or referring veterinarians were ocular cloudiness (14 kittens), blepharospasm (12 kittens), lethargy (5 kittens), ocular redness (3 kittens), or anisocoria, anorexia, hiding, or ocular discharge (2 kittens each). Ocular color change, heavy breathing, miosis, head shaking, ocular swelling, and trembling were each reported once. Within the same period, 8 kittens (2 spayed females, 1 intact female, 3 castrated males, and 2 intact males) had FIP-AU. Of those 8 kittens, there were 3 domestic shorthair, 1 domestic longhair, 1 Siamese, 1 Burmese, 1 Pixie Bob, and 1 Sphinx. No kittens were littermates, and all were from separate households. Uveitis was diagnosed in 8 different months with no obvious seasonality observed. Reported duration of ocular signs was about 1 month (4 kittens), 2 months (1 kitten), or 3 months (3 kittens). Clinical abnormalities commonly reported by caregivers or referring veterinarians were lethargy (7 kittens); ocular discharge or anorexia (4 kittens each); or ocular cloudiness, anterior chamber opacities, or sneezing (3 kittens each). Blepharospasm, hyphema, iridal discoloration, coughing, ataxia, or inability to walk were each reported in 2 kittens. A wide diversity of other clinical signs was reported only once. No significant differences in median age at first visit or sex distribution (without consideration of neuter status) were detected between the FURU and FIP-AU populations (Supplementary Table S1). However, kitten source varied significantly between the 2 populations (P < .001); the majority of the FURU population were sourced from shelters and none from breeders, whereas all kittens with FIP-AU were strays or from breeders. This was also reflected in the tendency for kittens with FIP-AU to be purebred (P = .06). A significant difference in duration of ocular signs prior to first ophthalmic examination was not detected (P = .14); however, (where recorded) this period was > 60 days in 3 of 5 kittens with FIP-AU versus ≤ 2 weeks in all kittens and ≤ 7 days in all but 1 of the 18 kittens with FURU.

Ophthalmic examination findings

At initial presentation, there were 29 eyes with FURU; 15 kittens were affected unilaterally (6 right eyes and 9 left eyes) and 7 kittens were affected bilaterally (Figure 1). Kitten number 22’s left eye was enucleated at 3 weeks of age for a disease unrelated to this study and prior to uveitis developing in its remaining eye. It therefore contributed data from 1 eye only throughout this study. Five of the 15 kittens initially presented with unilateral uveitis were subsequently affected in the contralateral eye; however, median time between each eye being affected was 45 days (range, 7 to 156 days; Figure 1, Figure 2, and Figure 3). Therefore, considering the entire study period, 10 kittens were affected unilaterally (5 right eyes and 5 left eyes) and 12 kittens were affected bilaterally, for a total of 34 eyes (Figure 1). By comparison, at initial presentation, 4 kittens with FIP-AU were affected unilaterally (3 right eyes and 1 left eye) and 4 kittens were affected bilaterally. The number of affected eyes did not change throughout the study. Therefore, data from 12 eyes are included.

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Clinical time course of 34 eyes of 22 kittens with feline undifferentiated resolving uveitis. Note that some kittens were affected unilaterally, some bilaterally and synchronously, and some bilaterally and asynchronously. Data for the right and left eyes of each kitten occupy a single row. Visits (visit numbers 1 to 8) were at various intervals. Black cells represent visits at which uveitis was detected, dark gray cells represent visits at which uveitis was considered resolving or was medically controlled, and light gray cells represent visits at which uveitis was absent. One kitten (kitten number 22) was enucleated prior to study entry and so could only be affected unilaterally. Although kitten number 5 was last examined only 4 days after onset of uveitis (at which time the uveitis was resolving), that kitten’s primary care veterinarian described normal eyes without history of recurrence 36 weeks after last examination at our hospital. For kitten number 7, the right eye is never shown as “affected” because the owner self-initiated treatment for that eye between visits using medications prescribed for the left eye. At the subsequent visit, uveitis was confirmed in the right eye and was therefore classified as “resolving.”

Citation: Journal of the American Veterinary Medical Association 2026; 10.2460/javma.25.07.0469

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Right and left eyes of a 6-month-old spayed female domestic shorthair kitten with bilateral but asynchronous feline undifferentiated resolving uveitis (kitten number 19 from Figure 1). A—At initial presentation, the left eye had episcleral and conjunctival hyperemia, aqueous flare and cell, keratic precipitates, rubeosis iridis, iridal thickening, and miosis; the right eye was normal. B—One week later, the left eye was normal; the right eye had episcleral and conjunctival hyperemia, diffuse subtle corneal edema, a fibrinous clot in the anterior chamber, and rubeosis iridis. C—Both eyes were normal 2.8 years after the initial presentation.

Citation: Journal of the American Veterinary Medical Association 2026; 10.2460/javma.25.07.0469

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Right and left eyes of a 2-month-old female spayed domestic shorthair kitten with bilateral but asynchronous feline undifferentiated resolving uveitis (kitten number 18 from Figure 1) showing 4 visits over 19 months. A and B—At initial presentation, the left eye had conjunctival hyperemia, chemosis, aqueous flare, anterior chamber fibrin and cell, rubeosis iridis, and vitreous cell; the right eye was normal. Both pupils have been pharmacologically dilated. C and D—Both eyes were normal 1.5 months later. E and F—The left eye was normal 5.8 months after the initial presentation; the right eye had conjunctival and episcleral hyperemia, chemosis, aqueous flare, anterior chamber cell, keratic precipitates, rubeosis iridis, and iridal thickening. G and H—No evidence of uveitis was seen in either eye 19 months after initial presentation.

Citation: Journal of the American Veterinary Medical Association 2026; 10.2460/javma.25.07.0469

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Ophthalmic examination findings at initial presentation were compared between all 29 eyes with FURU (Supplementary Figure S1 and S2) and 12 eyes with FIP-AU (Table 1; Supplementary Table S2; Supplementary Figure S3). Relative to eyes with FIP-AU, eyes with FURU were more likely to have episcleral hyperemia but less likely to have corneal edema, dyscoria, rubeosis iridis, iridal congestion/thickening, posterior synechia, keratic precipitates, or fundic abnormalities. In FURU, the fundus was normal in all 24 eyes examined, whereas abnormalities such as tapetal hyporeflectivity, and retinal hemorrhages, edema, separation, and vascular engorgement were noted in 6 of 11 examined eyes with FIP-AU (Figure 4). Corneal edema and chemosis were more severe in eyes with FIP-AU than in those with FURU.

Table 1Number of eyes unaffected versus affected with and severity of various ophthalmic abnormalities at initial presentation for 29 eyes of 22 kittens with feline undifferentiated resolving uveitis (FURU) and 12 eyes of 8 kittens with feline infectious peritonitis–associated uveitis (FIP-AU).

Clinical sign	FURU (29 eyes)	FIP-AU (12 eyes)	P value (statistical test)
Number of eyes unaffected:affected
Episcleral hyperemia	9:17	7:2	.05 (FE)
Corneal edema	26:2	1:6	< .001 (FE)
Dyscoria	25:1	4:5	.002 (FE)
Rubeosis iridis	12:13	0:11	.01 (FE)
Iridal congestion/thickening	18:7	1:6	.01 (FE)
Posterior synechia	24:1	2:8	< .001 (FE)
Keratic precipitates	26:2	3:7	< .001 (FE)
Fundic abnormalities	24:0	5:6	< .001 (FE)
Median (range) severity
Episcleral hyperemia	1 (0–3)	0 (0–1.5)	.03 (MW)
Corneal edema	0 (0–1)	1 (0–2)	< .001 (MW)

Not all signs were reported for all eyes. Only those clinical signs for which statistical significance was demonstrated are shown. FE = Fisher exact test. MW = Mann-Whitney rank sum test.

Clinical signs with P > .05 are available in Supplementary Table S2. Refer to the Methods for the grading system.

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Fundus of the right (A) and left (B) eyes of a 9-month-old castrated male domestic longhair kitten with bilateral and synchronous feline infectious peritonitis–associated uveitis. Both eyes had multifocal poorly-demarcated, hyporeflective, gray-white chorioretinal lesions within the tapetal fundus—often perivascularly. There was also bilateral conjunctival hyperemia, chemosis in the right eye, and aqueous flare, anterior chamber cell, and iridal thickening in the left eye at this visit.

Citation: Journal of the American Veterinary Medical Association 2026; 10.2460/javma.25.07.0469

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Clinicopathologic data

Of the 22 kittens with FURU, 16 were assessed using CBC (n = 16), serum biochemistry panel (12), or urinalysis (3) at least once. Of the 8 kittens with FIP-AU, 5 underwent assessment using CBC (n = 4), serum biochemistry panel (5), or urinalysis (3) at least once. Considering all CBC and biochemistry results across the study, kittens with FIP-AU were more likely than those with FURU to have anemia, leukocytosis with neutrophilia, hyperproteinemia with hyperglobulinemia, hyperglycemia, or hyperbilirubinemia (Supplementary Table S3); however, the magnitude of these changes differed significantly between the 2 populations for hyperphosphatemia only, but this was measured on only 2 occasions in only 1 kitten with FIP-AU. Hyperproteinemia, hyperglobulinemia, and hyperbilirubinemia were seen only in kittens with FIP-AU. Urinalysis results were unremarkable in kittens from either population.

Infectious disease testing

Fourteen of 22 kittens with FURU were screened for at least 1 infectious disease. These kittens were tested for serum antibodies to FIV (n = 10), Toxoplasma gondii (8), Dirofilaria immitis (1), or feline panleukopenia virus (FPV; 1) and antigens of FeLV (10) or Cryptococcus spp (5). One kitten (kitten number 16; Figure 1) underwent PCR on whole blood for Bartonella spp, feline herpesvirus type 1, T gondii, and FeLV. All results of all tests in the FURU population were negative except for the FPV titer (1:2048). Because FPV is not a reported cause of uveitis, this kitten was retained in the FURU group. Six of 8 kittens with FIP-AU were screened for at least 1 infectious disease. These kittens were tested for serum antibodies to FIV (n = 5), Toxoplasma gondii (4), or Bartonella spp (1) and antigens of FeLV (5) or Cryptococcus spp (1). One kitten underwent PCR on whole blood for Mycoplasma haemofelis. Results of all tests except Bartonella serology (reported as “1+”) were negative. Serum feline coronavirus (FeCoV) antibodies were detected in 7 of 11 kittens with FURU. Median FeCoV titer in these kittens was 1:400 (range, 1:50 to 10,240). One kitten with a FeCoV titer of 1:100 was tested for FeCoV RNA in whole blood using PCR; none was detected. Considering kittens with FIP-AU, serum FeCoV titers were positive in 3 of 4 tested (1:1,600, 1:6,400, and ≥ 1:6,400, respectively). The kitten with the 1:6400 titer also had FeCoV PCR performed on blood (which was negative) and on aqueous humor (which was positive). Coronavirus RNA was not found in blood from a second kitten in which FeCoV serology was not performed. The proportion of kittens with a positive FeCoV titer did not differ significantly between the 2 populations (P = 1.000; Fisher exact test), nor was there a significant difference in median titer of kittens with FIP-AU versus those with FURU (P = .18; Mann-Whitney rank sum test).

Diagnostic imaging

Considering the FURU population, thoracic radiography and abdominal ultrasound were performed on 1 kitten. No relevant abnormalities were noted. For kittens with FIP-AU, thoracic radiography was performed in 4 kittens and abdominal ultrasound in 5 kittens. All kittens had at least 1 abnormality observed. Thoracic radiographs revealed moderate diffuse bronchial pattern (n = 1) or mild diffuse interstitial pulmonary pattern (1). Abdominal ultrasonography revealed diffusely distended intestines (n = 2), esophageal gas (1), hypoechoic liver with increased portal vascular detail (1), mild hepatomegaly (1), mildly echogenic gallbladder wall (1), hyperechoic (1) or hypoechoic (1) splenic mottling, enlarged adrenal gland (1), enlarged mesenteric (3), ileocolic (1) or unspecified (1) lymph nodes, bilateral renomegaly (1), or free peritoneal fluid (2).

Treatment

Kittens with FURU received topically administered corticosteroids (n = 21), mydriatic/cycloplegic agents (3), antibiotics (2), and antiglaucoma drugs (3), as well as systemically administered antibiotics (5), corticosteroids (4), famciclovir (2), NSAIDs (2), analgesics (2), or subcutaneous fluids (1). Only 1 kitten with FURU received no anti-inflammatory agents (kitten number 1; Figure 1), and their uveitis resolved despite this. This kitten did, however, receive famciclovir and doxycycline, the latter of which is known to have some immunomodulating as well as antibacterial effects. Kittens with FIP-AU received topically administered corticosteroids (n = 6), mydriatic/cycloplegic agents (4), lubricants (2), antibiotics (1), cidofovir (1), or antiglaucoma drugs (1), as well as systemically administered corticosteroids (3), famciclovir (1), NSAIDs (1), or iron dextran (1).

Duration of Uveitis

For the FURU population, median duration of uveitis was 10 days (range, 5 to 84 days), with uveitis resolving in less than 28 days on 29 of 33 occasions. Telephone/email follow-up with owners and/or referring veterinarian was available for all kittens with FURU. Median time from initial presentation until telephone/email contact was 4.7 years (range, 1.2 to 18.2 years), during which all were confirmed to be alive and free of signs suggestive of FIP. Uveitis did not resolve in any kitten with FIP-AU, therefore duration of ocular signs was not calculated. Instead, median period from first clinical signs until death/euthanasia was calculated as 16 weeks (range, 2.7 to 29.1 weeks), and period from diagnosis of uveitis to death/euthanasia was 38 days (range, 1 to 92 days). Figure 5 shows Kaplan-Meyer survival curves for time to uveitis resolution for the FURU population and time to death for kittens with FIP-AU.

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Kaplan-Meier survival curves showing the probability throughout the clinical course of kittens with feline undifferentiated resolving uveitis achieving ophthalmic recovery (A) or kittens with uveitis associated with feline infectious peritonitis dying /being euthanized (B).

Citation: Journal of the American Veterinary Medical Association 2026; 10.2460/javma.25.07.0469

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Discussion

This study highlights a form of uveitis in kittens with many clinical signs considered characteristic of FIP-AU,⁶ but from which all recovered without sequelae and without antiviral therapy effective against FIP. Our coarse prevalence data suggest that FURU occurs in about 7% of all kittens with uveitis of any form. This prevalence and the similarities with FIP-AU make it critical that veterinarians are aware of this syndrome and attempt to differentiate it from FIP-AU. Ideally, all kittens with uveitis would undergo extensive diagnostic testing; however, this is often not financially feasible, false negative and positive test results are possible, and a definitive diagnosis is not made in the majority of feline uveitis.^4,5 As such, our population (each of which underwent a different level of diagnostic investigation) is a pragmatic representation of practice. Clinical judgment following a complete syndromic assessment is therefore essential in all cases. In hopes of refining early differentiation of FURU and FIP-AU, this study highlights similarities and distinctions between these 2 syndromes. Since age at first presentation was an entry criterion for both populations, it is unsurprising that no significant difference in age between them was detected. However, we also failed to detect significant differences between populations for sex distribution, indoor/outdoor lifestyle, seasonality, or number of cats in the household, which were not entry criteria. This underscores the care needed not to confuse these 2 syndromes based on signalment alone. Analysis of littermate and housemate data provides further insight. No littermates were noted in the FIP-AU group, which is consistent with the widely accepted “internal mutation theory” whereby enteric FeCoV mutates to become FIP virus in individual cats rather than FIP virus being transmitted among cats.⁹ Meanwhile, there was only 1 pair of littermates with FURU, and they were living in the same home, which suggests that FURU, too, is not caused by a highly communicable pathogen. This is further supported by the fact that commonly incriminated infectious agents were not diagnosed in those kittens tested. However, not all kittens underwent infectious disease diagnostic testing, and some received antibacterial agents or famciclovir. Additionally, some important differences in signalment and history were observed between the populations. Kittens with FURU were predominantly domestic kittens and often sourced from shelters, whereas those with FIP-AU were frequently purebred and acquired from breeders or found as strays. This aligns with prior findings that purebred kittens, particularly those from multicat settings, are at higher risk of FIP.¹⁰ Finally, kittens with FURU in the present study tended to have a short duration of ocular signs (1 to 2 weeks) relative to those with FIP-AU where disease frequently exceeded 2 months. Prevalence and magnitude of individual clinical signs of uveitis were largely similar between the 2 populations, as was expected since kittens with FURU were selected because their signs largely mimicked those seen in FIP-AU. Therefore, differences between the 2 populations are particularly helpful for differentiating FURU from FIP-AU. For example, kittens with FURU were more likely than kittens with FIP-AU to have episcleral hyperemia, whereas kittens with FIP-AU were more likely to have corneal edema, dyscoria, rubeosis iridis, iridal congestion/thickening, posterior synechia, and keratic precipitates; and, when present, corneal edema and chemosis were more severe in FIP-AU than in FURU. Given that episcleral hyperemia is considered a hallmark sign of uveitis, especially when uveitis is severe, it is striking that this finding was seen more commonly with FURU than with FIP-AU. While this speaks to the severity of uveal inflammation seen with FURU, it is also possible that chemosis (which was more marked in FIP-AU than in FURU) and marked blepharospasm made episcleral hyperemia more challenging to see in FIP-AU. Perhaps the most discriminating clinical sign was that no eyes with FURU had fundic abnormalities whereas 6 of 11 eyes with FIP-AU had evidence of chorioretinitis such as retinal hemorrhages, separation, or vascular engorgement suggesting that a fundic examination is critical in all kittens with anterior uveitis. Laterality of uveitis may also offer important clues as to final diagnosis. Although both FURU and FIP-AU could be unilateral or bilateral, no unilaterally affected kittens with FIP-AU became bilaterally affected before death/euthanasia due to FIP, whereas 5 of 15 unilaterally affected kittens with FURU subsequently became bilateral at a median of 45 days (and in 1 case at 156 days) after initial presentation making this an important distinction between the 2 populations. This variability in clinical course also presented difficulties for data analysis in this study. Kittens with FURU showed notable variation in laterality of uveitis at and after presentation such that they occupied 1 of 5 categories: 1) Unilateral uveitis on a single occurrence in kittens with 2 eyes; 2) Unilateral uveitis by default due to enucleation; 3) Unilateral recurrent uveitis (potentially from different causes in each instance); 4) Bilateral synchronous uveitis; and 5) Bilateral asynchronous uveitis (potentially from different causes in each instance). As with all ophthalmic studies, this presents a dilemma as to whether separate disease events in the same kitten should be treated as statistically dependent or independent events. For many reasons, we chose to treat them as independent events. First, we have no evidence that the etiopathogenesis for the first uveitic event was the same as that for the second (whether that second event occurred ipsilaterally or contralaterally). Second, the period of up to 5 months between eyes being affected is likely to affect the degree of dependence of data. Given these young kittens were developing and often changing housing, many important clinical confounders such as lifestyle, nutrition, anatomic and physiologic development, and immunologic maturity would change notably during the time between the first and second uveitis event. Third, it is likely that uveitis in 1 eye alters the specific and nonspecific immunologic response to a subsequent uveitis in that or the contralateral eye. Finally, the alternative approach using multilevel regression models of first versus subsequent uveitic events was considered problematic for the type of data generated at the eye level, and—given the low P values we currently demonstrate for many of these analyses— reanalysis using multi-level regression models is unlikely to change a significant result to a nonsignificant result. Therefore, wherever clinically reasonable, we analyzed differences at the kitten level (age, breed, sex, source, lifestyle, number of cats in household, etc, in Supplementary Table S1; serum biochemistry values, serologic test results, CBC values, UA, etc, in Supplementary Table S3), whereas for all the reasons noted above, ocular signs were assessed at the eye level (Table 1; Supplementary Table S2). No data were assessed at the occurrence level. Clinical course may also provide useful differentiating data, albeit sometimes retrospectively. From time of first visit, clinical course was notably longer in kittens with FURU than in kittens with FIP-AU. Using survival curves (Figure 5) as a means of estimating this, there was a 75% probability that ophthalmic disease would resolve within 3 weeks of the first examination for FURU versus a 50% probability of death within about 5 weeks in kittens with FIP-AU. Presence of systemic signs was not an entry criterion for either population, and lethargy and anorexia as well as respiratory and neurologic signs were reported for kittens in both populations. As such, presence of systemic signs in a kitten with uveitis should not be used to suggest that a more serious cause such as FIP is likely. Although we did not assess severity of any systemic signs in the present study, it is possible that these were sometimes perceived as more concerning or chronic in kittens with FIP-AU because these kittens more frequently underwent abdominal or thoracic imaging than did kittens with FURU. Although some clinicopathologic differences between populations were significant (anemia, leukocytosis with neutrophilia, hyperproteinemia with hyperglobulinemia, hyperglycemia, and hyperbilirubinemia), these differences were in prevalence only, not magnitude, and for all but 3 of these the same hematologic/biochemical change was seen in at least 1 kitten in both populations, making none of these reliable as a sole differentiating criterion. Exceptions were hyperproteinemia, hyperglobulinemia, and hyperbilirubinemia, each of which was seen only in kittens with FIP-AU. These changes have been previously reported as common in cats with FIP,¹¹ but studies have not always included a control group.¹⁰ Perhaps most critically, neither likelihood of a positive FeCoV titer nor titer magnitude was greater in kittens with FIP-AU than in kittens with FURU. This reinforces previous data suggesting that serology alone must not be used to diagnose FIP.¹¹ Finally, it is worth noting that both populations lacked compelling positive infectious disease test results other than coronavirus seropositivity. Although this was expected for kittens with FURU since this was an entry criterion, for those with FIP-AU, it suggests that coinfections with FIP virus are uncommon. This study was not designed to assess treatment or clinical management of these 2 populations. However, data presented here regarding FURU and its close similarity to FIP-AU present a dilemma for clinicians considering use of drugs such as remdesivir or GS-441524 in cats with uveitis considered typical of FIP-AU. This is especially important given that uveitis in a kitten with FIP may necessitate a longer course and/or higher dose of antiviral drugs, and carry a more guarded prognosis than for a kitten without ocular involvement.^12–15 If a kitten with FURU is presumptively misdiagnosed as having FIP-AU, veterinarians would present owners of the kitten with a worsened prognosis and presumably discuss high doses of expensive drugs which, in some jurisdictions, are not even legally available. As a result, owners may be deterred from or hesitate beginning antiviral therapy or even empirical therapy for uveitis; some may even consider euthanasia. Conversely, a kitten with FIP-AU requires early institution of high-dose targeted antiviral therapy and appropriate supportive care, which, if delayed, may lead to poorer outcomes. In this way the identification of FURU along with the availability of effective antiviral therapy for FIP presents veterinarians and owners with a dilemma. It is, therefore, essential that veterinarians consider FURU as a differential diagnosis, conduct a syndromic assessment of the patient (including especially a fundic examination), and, at a minimum, encourage empirical uveitis therapy for kittens in which either diagnosis is possible. Furthermore, recognition of FURU necessitates that clinical improvement in any kitten with uveitis while on antiviral therapy must not be used alone to confirm the FIP diagnosis. Differentiating FURU from FIP-AU is challenging, but broad awareness of this syndrome is a critical first step. Taken together, our data highlight the importance of comprehensive history-taking and clinical evaluation in differentiating these 2 syndromes confirming earlier work¹¹ suggesting that FIP is a syndromic diagnosis. Regardless, data from the present study offer some important means by which veterinarians may increase the likelihood of differentiating FIP-AU from FURU, or at the very least limit the frequency with which FIP-AU is misdiagnosed. Important among these are: 1) FIP-AU may be unilateral (approximately 50% of kittens in the present study); 2) Anterior chamber fibrin and cell are seen commonly in both FURU and FIP-AU and should not be used to differentiate the 2 syndromes; 3) Severe chemosis, corneal edema (especially if severe), dyscoria, rubeosis iridis, iridal congestion/thickening, posterior synechia, and keratic precipitates are more commonly seen with FIP-AU but are not diagnostic alone; 4) Chorioretinitis is common with FIP-AU (> 50% of eyes) but was never seen in FURU, making fundic examination a critical assessment in kittens with uveitis; 5) Clinicopathologic abnormalities should be interpreted cautiously, but hyperproteinemia, hyperglobulinemia, and hyperbilirubinemia were never seen in kittens with FURU; 6) FeCoV titers alone cannot be used to differentiate FURU from FIP-AU; 7) Despite being initially severe and even fibrinous/granulomatous in appearance, FURU is responsive to empirical therapy without use of antiviral agents with known efficacy against FIP; 8) Response to antiviral therapy cannot be used alone to confirm the diagnosis of FIP.

Supplementary Materials

Supplementary materials are posted online at the journal website: avmajournals.avma.org.

__________________________________________________________________________________ DVM 360 News | Key takeaways from AAHA’s 2026 oncology guidelines  Author(s)Bob Alaburda, Associate Editorial Director  January 7, 2026  AAHA’s 2026 oncology guidelines aim to update diagnostics, staging, treatment priorities, and team workflows to help primary care clinics detect, stage, and manage cancer while preserving patient quality of life.   Cancer is a leading cause of illness and death in older dogs and cats, affecting roughly 50% of dogs and about 30% of cats older than 10 years. The American Animal Hospital Association’s (AAHA) 2026 Oncology Guidelines synthesize current evidence and expert consensus into actionable recommendations for the primary care team from diagnosis and staging to treatment options, supportive care, referral triggers, and follow-up.1,2  Here are a few key takeaways. A link to the full guidelines can be found in the reference list below this article.  Make a definitive diagnosis before planning therapy  AAHA emphasizes that a cytologic or histopathologic diagnosis is necessary to determine prognosis and guide therapy.1-3 When fine-needle aspirate is inconclusive or additional information is required (for example, tumor grade), pursue biopsy and histopathology rather than assuming tumor behavior.3   Use staging to guide treatment intent and timing  Staging is more than local vs metastatic classification. It clarifies treatment intent (curative vs palliative) and identifies appropriate imaging and nodal assessment. AAHA provides tumor-specific staging checklists and recommends thoracic imaging, abdominal ultrasound, and regional lymph node cytology or biopsy as indicated.3   Frame chemotherapy around quality of life  The primary goal of systemic therapy in veterinary oncology is maintaining the best possible quality of life while controlling disease. Most veterinary chemotherapy protocols are generally well tolerated. Adverse events are usually manageable when clinicians and owners anticipate them and monitor appropriately.1,4  Educate owners proactively about the likelihood of appetite changes during chemotherapy and provide concrete management strategies. Addressing appetite loss early helps pets remain on recommended treatment plans and improves overall well-being during therapy.1  Evaluate new drugs and biologics carefully  The guidelines stress understanding the risks, benefits, cost, and regulatory status of novel therapeutics (such as small-molecule inhibitors, monoclonal antibodies, and other biologics). Clinicians should not adopt new agents without reviewing available evidence, registration status, and monitoring requirements.4   Integrate supportive and symptomatic care from diagnosis onward  Supportive care—nutrition, pain management, antiemetics, wound and infection management, and psychosocial support for owners—is fundamental and begins at diagnosis. AAHA provides screening and treatment checklists aimed at maintaining function and comfort throughout therapy and survivorship.7,8 When initiating symptomatic care, thoroughly evaluate for comorbidities that may alter drug choice, dosing, or prognosis. This ensures supportive measures truly improve quality of life rather than introducing harm.1   Optimize the veterinary team’s role  Technicians and other team members play a central role in oncology workflows, including intake screening, weight and appetite tracking, pain scoring, client education, medication administration training, and documentation. Standardized technician checkpoints improve early detection of complications and support better quality-of-life decisions.8   Know when to refer and how to collaborate  AAHA outlines clear referral triggers: complex staging that requires advanced imaging, specialized surgery, administration of advanced systemic protocols, or when weighing curative versus palliative intent. Good referral relationships and succinct transfer-of-care notes streamline transitions and may improve outcomes.5,6   Adopt structured post-treatment monitoring  Tumor-specific follow-up schedules and standardized monitoring (physical exam, imaging, and laboratory testing) are recommended to detect recurrence or late treatment effects early. Integrating these schedules into practice management software reduces the risk of patients being lost to follow-up.9  References 

1. American Animal Hospital Association. 2026 AAHA oncology guidelines for dogs and cats. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/ 

1. American Animal Hospital Association. Section 1: overview of common cancers. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-1-overview-of-common-cancers/ 

1. American Animal Hospital Association. Section 3: tumor diagnostics and staging. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-3-tumor-diagnostics-staging/ 

1. American Animal Hospital Association. Section 5: therapeutic interventions. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-5-therapeutic-interventions/ 

1. American Animal Hospital Association. Section 6: consultations and referrals. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-6-consultations-and-referrals/ 

1. American Animal Hospital Association. Section 2: what’s new in veterinary oncology. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-2-whats-new-in-veterinary-oncology/ 

1. American Animal Hospital Association. Section 7: supportive and symptomatic care. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-7-supportive-and-symptomatic-care/ 

1. American Animal Hospital Association. Section 8: technician and team optimization. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-8-technician-and-team-optimization/ 

1. American Animal Hospital Association. Section 9: post-treatment monitoring and follow-up care. American Animal Hospital Association. Published January 1, 2026. Accessed January 7, 2026. https://www.aaha.org/resources/2026-aaha-oncology-guidelines-for-dogs-and-cats/section-9-post-treatment-monitoring-and-follow-up-care/ 

https://www.dvm360.com/view/key-takeaways-from-aaha-s-2026-oncology-guidelines

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AVMA News I New guidelines call for earlier diagnosis, intervention in feline dental disease 

Recommendations for when to refer to specialists included in FelineVMA guidance for the first time

Published on December 30, 2025 

The Feline Veterinary Medical Association (FelineVMA) has published new comprehensive guidelines that raise the bar for oral health care in cats by providing evidence-based recommendations spanning diagnosis, treatment, anesthesia, prevention, and client communication.  Appearing in the November issue of the Journal of Feline Medicine and Surgery, the 2025 FelineVMA Feline Oral Health and Dental Care Guidelines is the most detailed resource on feline dentistry to date, outlining advances in tooth resorption classification, earlier intervention for feline chronic gingivostomatitis (FCGS), and structured referral pathways.  By promoting routine use of intraoral radiography, consistent client education, and spectrum-of-care approaches, the guidelines aim to reduce untreated oral pain and improve long-term outcomes for feline patients.  Oral and dental diseases are common health problems in the domestic cat, but can be difficult to identify given the cat’s powerful instinct to conceal illness and pain, according to the guidelines. The document is written for all members of the veterinary team and includes guidance on supporting owners as active participants in their cat’s dental health care.  “Oral and dental diseases are among the most common health problems in cats, yet they’re often unrecognized,” Dr. Heidi Lobprise, co-chair of the guidelines task force, said in a press release. “These guidelines equip veterinary professionals with practical, evidence-based tools to diagnose and manage these conditions earlier and more effectively.” 

Guidelines highlights 

Periodontal disease (PD) remains the most prevalent oral condition in feline patients, with gingival inflammation reported in up to 96% of cats in some studies, according to the guidelines.  “The term PD encompasses gingivitis, which is the early reversible stage of the disease process, and the progressive changes leading to periodontitis, where there is an irreversible loss of the supporting structures of the teeth. In gingivitis, the gum tissue may be erythematous, swollen or painful,” the guidelines state.  Periodontal disease indices and steps for assessment are included in the guidelines, which encourage full-mouth dental radiography to determine the amount of alveolar bone loss for each tooth and whether the attachment loss is horizontal or vertical.  Additional areas of focus include feline chronic gingivostomatitis (FCGS), tooth resorption, and trauma; patient assessment, evaluation, and documentation; anesthesia and analgesia; and specific considerations in relation to tooth extraction.  Early extraction therapy—partial caudal or full-mouth—is reaffirmed as the most effective treatment for FCGS, with cited resolution or substantial improvement rates approaching 67% in some studies. Long-term corticosteroid use is discouraged due to limited efficacy and risks of immunosuppression.  For refractory cases, the guidelines review adjunctive therapies including ciclosporin, interferon omega, and stem cell therapy, while noting many remain supported only by limited or anecdotal evidence.  Expanded coverage is given to tooth resorption (TR), a common and progressive disease affecting 28% to 67% of cats, depending on the population.  “Despite various hypotheses, the etiology of TR remains unclear,” the guidelines state. “Studies have shown an increase in prevalence with increasing age, while findings regarding a specific breed predisposition have not been consistent.”  Pain alleviation is the principal aim of treatment.  “Unfortunately, no prevention for tooth resorption has been found and there is no method of stopping the progression of an already existing lesion,” the guidelines state, which list tooth extraction, crown amputation, and monitoring as treatment options.  Additional topics covered in the guidelines include oral carcinomas, equipment considerations, and use of antibiotics. 

Surgery and referrals 

The FelineVMA guidelines reiterate that comprehensive feline dental assessment and treatment cannot be performed in awake patients. Full-mouth dental radiography, thorough charting, scaling, and surgical procedures require general anesthesia and multimodal analgesia. Detailed workflow recommendations cover preanesthetic evaluation, the typical workflow and staging of oral and dental surgical procedures, postoperative care, and nutritional support.  For the first time, the FelineVMA guidelines offer explicit criteria to help general practitioners determine when referral to a board-certified veterinary dentist is advisable, which are as follows: 

• Retained or displaced root tips 

• Maxillofacial trauma or jaw fractures 

• Suspected oral masses requiring biopsy or advanced imaging 

• Systemically compromised or high-risk anesthetic patients 

• Need for full-mouth extractions, complex endodontics, or orthodontics 

• Practices without intraoral radiography capability or facing high risk of iatrogenic fracture 

The task force encourages maintaining relationships with dental specialists for consultation and continuity of care.  In addition, the guidelines feature supplemental online resources, such as videos, a feline dental chart, feline dental care brochure, feline Stomatitis Disease Activity Index (SDAI) scoring chart, and additional information on periodontal disease. Resources for cat owners can be found on the FelineVMA website.  Task force co-chair Dr. Kelly St. Denis emphasized the guidelines’ attention to veterinary team alignment and owner education: “By educating caregivers with consistent, science-based messaging, we can ensure more cats receive the dental care they need and deserve.”   https://www.avma.org/news/new-guidelines-call-earlier-diagnosis-intervention-feline-dental-disease?utm_source=delivra&utm_medium=email&utm_campaign=todays-headlines-news   ____________________________________________________________________________________ DVM 360 | Understanding oncology diagnostics and therapeutics  Multiple approaches to cancer treatment can be initiated by primary care veterinarians.  December 3, 2025  Author(s)Craig A. Clifford DVM, MS, DACVIM (Oncology), Christine Mullin VMD, DACVIM (Oncology)  What can primary care veterinarians do to provide care to patients with cancer? These approaches can help guide treatment.    Staging is a critical step in cancer patient management, but it does not always require referral to a specialist to be performed effectively. Most staging procedures—such as complete blood count, serum chemistry panel, cytologic evaluation of regional lymph nodes, and 3-view thoracic radiographs—are standard diagnostic tests readily available in general practice.    These tools provide essential information about the extent of disease, metastatic potential, and overall patient health, guiding both treatment decisions and client expectations. For example, aspirating a regional lymph node in a dog with a mast cell tumor or obtaining thoracic radiographs in a soft tissue sarcoma or osteosarcoma case are impactful yet straightforward steps that can be performed in-house. When these results accompany a referral, they not only streamline case management but also reduce client costs and improve continuity of care. By recognizing that cancer staging is based upon the same diagnostic principles used in primary care, veterinarians can confidently contribute to accurate diagnosis, timely treatment planning, and collaborative oncology care.   Key tests for primary care  

• Lymphoma: Complete blood count (CBC), serum chemistry, consider 3-view thoracic radiographs with radiologist review 

• Mast cell tumor: CBC, serum chemistry, consider regional lymph node cytology 

• Soft tissue sarcoma: CBC, serum chemistry, 3-view thoracic radiographs with radiologist review 

• Osteosarcoma: CBC, serum chemistry, radiographs of affected limb, 3-view thoracic radiographs with radiologist review 

• Melanoma: Mass measurement and photo, CBC, serum chemistry, 3-view thoracic radiographs with radiologist review, regional lymph node cytology 

Clinical takeaways  Performing baseline staging in-house supports faster case turnover, more informed prognostication, and smoother communication with oncology referral centers. Most initial cancer staging can be efficiently and accurately performed by primary care veterinarians, expediting or even in some cases replacing oncology referral and reducing client cost. 

Diagnosing lymphoma with a blood test 

The IDEXX Cancer Dx is a new blood-based screening/diagnostic panel aimed at detecting canine lymphoma from serum or whole blood. It reports the presence or absence of lymphoma-associated circulating biomarkers and, when positive, can provide a B- vs T-cell phenotype classification in some cases.1  Key performance numbers2: 

• Sensitivity: ~79% for dogs with lymphoma in IDEXX’s internal validation. 
• Specificity: ~99% versus healthy controls and dogs with inflammatory disease/other cancers in the same internal dataset. 

Practical details: 

• Sample: single blood draw (serum or whole blood). Interference from mild–moderate hemolysis, lipemia, or icterus is reportedly minimal. 
• Intended use cases highlighted by IDEXX: 
• Dogs suspected of having lymphoma 
• Cancer screening for apparently healthy “at-risk” dogs (IDEXX suggests integration within wellness panels for older dogs). 
• Cost/rollout: IDEXX promotes the test as low-cost (advertised as starting around US$15 as an add-on) and has been available in the US and Canada as of March 2025.1 

How to use it in primary care: 

• If lymphoma is suspected clinically (lymphadenopathy, constitutional signs, cytology suspicious): Cancer Dx can be run on the blood sample as a noninvasive adjunct, but positive results still require confirmation with cytology/biopsy/flow/PCR for antigen receptor rearrangement (PARR) as clinically indicated. A negative result does not rule out lymphoma because sensitivity is <100%. 
• If used for screening (as an add-on in older / at-risk dogs): discuss with owners that the test increases the chance of detecting lymphoma earlier, but is not a guarantee—explain the possibility of false negatives and what you’d do if the test is positive (confirmatory diagnostics, staging conversation). 

Clinical takeaways The IDEXX Cancer Dx is a practical, low-cost blood test that helps detect canine lymphoma earlier and in some cases supplies phenotyping information useful for initial case planning. It’s a reasonable adjunct for dogs with clinical suspicion and an attractive screening add-on for older/at-risk dogs — but it is not diagnostic by itself. Use positive results to prompt confirmatory diagnostics such as cytology/biopsy/flow cytometry/PARR, and use clinical judgment for negative results because sensitivity is not 100%. Consider the current evidence base (IDEXX internal validation data only) and watch for independent peer-reviewed studies as they emerge. 

Immunophenotyping Canine Lymphoma 

Immunophenotyping (determining B-cell vs. T-cell origin) is now considered a standard part of lymphoma diagnosis because it directly influences prognosis and treatment expectations. Multiple studies confirm that dogs with T-cell lymphoma have shorter survival times and lower response rates to standard CHOP chemotherapy compared to dogs with B-cell lymphoma. 

• In one study, T-cell lymphoma had only a ~50% response rate to single-agent doxorubicin, versus nearly 100% for B-cell lymphoma.3 
• T-cell protocols incorporating alkylating agents such as lomustine (CCNU) have shown partial responses in ~60% of cases and complete responses in 17%.4 
• Modified multiagent protocols (eg, L-MOPP, CCNU-based CHOP variants) may offer benefit, but toxicity and practicality limit their use in general practice.5 
• A prospective study comparing CHOP +/- the investigational agent AT-005 in T-cell lymphoma demonstrated similar response rates (~65% CR) and median progression-free survival (64–103 days), confirming that outcomes remain inferior to B-cell lymphoma.6 

Methods for immunophenotyping  Flow cytometry (preferred): 

• Most informative test of all those available. Confirms B-cell vs. T-cell, but also provides additional prognostic markers that can indicate grade and expected behavior 
• Can be performed on tissue aspirate (ie, lymph node, organ) or fluid (ie, blood, effusions, CSF) 
• Requires live cells in media and overnight shipping 
• Available at multiple academic and reference labs 

PARR: 

• Can be performed on both cytology and biopsy samples 
• Only confirms B-cell vs. T-cell status, does not provide grade 
• Available at most academic and reference labs 

Immunocytochemistry (ICC): 

• Can be performed on cytology slides 
• Somewhat subjective 
• Available at some academic and reference labs 

Clinical takeaways Primary care veterinarians can play a crucial role by determining lymphoma immunophenotype before referral and treatment initiation, allowing the care team and pet owners to have a more informed and directed conversation about treatment options and expected prognosis.  B-cell: CHOP-based therapy remains standard, potentially good long-term prognosis.  T-cell: Expect shorter remission; consider referral or alternate protocols. 

Cytologic Grading of Mast Cell Tumors (MCTs) 

Traditional histologic grading remains the gold standard, but cytologic grading is validated as a noninvasive, predictive tool when tissue biopsy isn’t feasible or clinically indicated. Studies have shown that specific cytologic features—including mitotic figures, multinucleation, nuclear atypia, and karyomegaly—strongly correlate with histologic grade and outcome.  Cytologic grading predicted histologic grade in 94% of cases.7  Cytologic grading carries an 88% sensitivity and 94% specificity relative to histopathology.8  Compared to low-grade tumors , cytologically high-grade MCTs are 25–39 times more likely to result in death within 2 years.7   Clinical takeaways  For general practitioners, cytologic grading provides a rapid, low-cost prognostic tool that can guide surgical planning and inform prognosis. Communicate with reference laboratory to ensure that cytologic grading can be provided for MCT submissions.     Noninvasive diagnosis of Transitional Cell Carcinoma (TCC)  The BRAF mutation test (CADET BRAF Mutation Detection Assay) represents one of the most impactful molecular diagnostics in veterinary oncology. Independent studieshave identified a single-point mutation (V595E) in the canine BRAF gene that is present in ~85% of TCC/urothelial carcinoma (UC) cases, but absent in benign or inflammatory bladder conditions. 9,10    This assay detects the mutant DNA in urine sediment, allowing: 

• Noninvasive diagnosis without aspirate, cystoscopy, or surgical biopsy 

• Early detection—often months before clinical signs 

• Monitoring for response to treatment and early detection of recurrence 

A secondary test now detects an additional ~10% of previously negative cases. The test is offered through Antech Diagnostics (BRAF Plus; Sentinel Biomedical platform).    Clinical takeaways   

• Consider this test for any dog with persistent hematuria, pollakiuria, or suspicion of a urinary tumor. 

• Submit a free-catch or catheterized urine sample for CADET BRAF testing before pursuing more invasive diagnostics such as prostatic wash for cytology, cystoscopy, or biopsy. 

• This test eliminates the need for needle aspiration of urinary tumors, a known risk for tumor seeding. 

• This test is 100% specific, so can be performed in dogs with known or suspected urinary tract infection (UTI) without concern for a false positive result. 

Oncologic therapies available in primary care practice  Use of verdinexor (Laverdia-CA1; Dechra)    Verdinexor is an oral anticancer medication conditionally approved by the FDA for the treatment of lymphoma in dogs. It belongs to a novel class of compounds known as Selective Inhibitors of Nuclear Export (SINE), which work by trapping tumor suppressor proteins inside the nucleus, thereby restoring normal control of cell growth and promoting cancer cell death.    For the primary care veterinarian, verdinexor offers an important at-home treatment option for canine lymphoma—particularly when referral for multiagent chemotherapy is not possible, or when a client prefers palliative care that still provides measurable clinical benefit.     Efficacy and clinical use   In a multicenter phase II study of dogs with both B-cell and T-cell lymphoma, verdinexor achieved a clinical benefit rate of 55% (stable disease or better), with a median duration of benefit of 71 days (range 21–273 days). Notably, T-cell lymphoma cases, which are often less responsive to traditional chemotherapy, still showed a 71% clinical benefit rate.11 Commonly reported adverse effects are mild and include transient loss of appetite, lethargy, or gastrointestinal upset, which can often be managed symptomatically.    This makes verdinexor a reasonable monotherapy option for:   

• Dogs that cannot undergo intravenous chemotherapy. 

• Patients that have relapsed after CHOP-based treatment. 

• Owners seeking palliative oral therapy that maintains quality of life.   

How SINE drugs work with other chemotherapy agents    In addition to its single-agent activity, the SINE drug class has shown synergistic and sensitizing effects when combined with other chemotherapeutics such as doxorubicin and platinum-based agents. These effects may help:   

• Sensitize lymphoma cells to respond better to chemotherapy. 

• Reverse or delay drug resistance that develops after cytotoxic treatment.   

Verdinexor vs prednisone: Impact on drug resistance    Historically, prednisone has been used for palliative treatment of lymphoma, but glucocorticoids can induce multi-drug resistance (MDR) by increasing P-glycoprotein expression in lymphoma cells—reducing the efficacy of subsequent chemotherapy and worsening prognosis.12    In contrast, verdinexor is not a substrate for P-glycoprotein, meaning it should not promote MDR or interfere with future chemotherapy response. In clinical studies, dogs receiving prednisone alone survived an average of 4–7 weeks, whereas verdinexor therapy offers a longer median benefit with potentially improved quality of life.11    Potential novel uses    Cutaneous (epitheliotropic) lymphoma is a challenging disease to treat, with lomustine & prednisone considered the current standard of care. New data suggests that verdinexor has efficacy vs. this form and may serve as a novel second line agent.13,14    Clinical takeaways   

• Verdinexor oral tablet can be prescribed and monitored in a general practice setting. 

• It provides a targeted, noncytotoxic option for dogs with newly diagnosed or relapsed lymphoma. 

• It can be considered a bridge between comfort care and referral for chemotherapy. 

• Technicians play a key role in client education—reviewing safe handling, side-effect monitoring, and adherence.   

Tigilanol tiglate (Stelfonta; Virbac)—A localized therapy for canine mast cell tumors (MCT)    Tigilanol tiglate is a novel anticancer protein kinase C activator that is FDA-approved for the treatment of certain canine MCTs. Tigilanol tiglate was originally isolated from the seed of the Australian tree Fontainea picrosperma and is now formulated for intratumoral injection.15 Tigilanol tiglate is approved for dogs with all grades of non-metastatic MCTs, including:   

• Any cutaneous MCT 

• Subcutaneous MCTs located at or distal to the elbow or the hock 

• Note: Tumors must be £10 cm3 in volume and accessible for intratumoral injection   

How it Works  

• Tigilanol tiglate (1 mg/ml) is injected via a single puncture site into the tumor, then the dose is distributed by fanning the needle throughout the tumor mass. 

• Dose to be injected is calculated based upon tumor volume (Modified Ellipsoid Method, in cm3): https://stelfonta.com/how-to-calculate-correct-stelfonta-dose/ 

• Once injected, tigilanol tiglate induces a rapid and localized inflammatory response and destruction of local blood supply to the tumor primarily via ischemic necrosis. 

• Healing of the affected area occurs with minimal scar formation. 

• Most wounds heal within 4-6 weeks; full healing was observed within 3 months in 98.2% of cases16 

Efficacy   In a prospective study, a single tigilanol tiglate treatment resulted in 75% complete response (CR) by 28 days, with that CR maintained in 94% of dogs by 84 days and 89% of dogs by 12 months.17 Dogs not achieving a complete response with the first treatment can receive a second treatment, which results in an improved overall CR rate of 88%. Another more recent study (showed similar results—75% CR rate after a single treatment, with that CR lasting at least 1 year in 64% of dogs.18    Adverse Effects    Adverse effects of tigilanol tiglate are typically low grade, transient, and directly associated with the mode of action. These include:   

• Wound formation (possibly extensive) following tumor necrosis and slough  

• Localized pain, swelling, erythema, and bruising at the tumor site  

• Lameness in a treated limb  

• Regional lymph node enlargement  

Suggested visit schedule:   

• Day 0 – injection  

• Day 2 or 3 – check site to confirm necrosis occurring  

• Day 7 – assess wound  

• Day 28 – reassess wound  

• Further visits will be dependent upon patient response and wound healing  

Tricks of the trade  

• Perform cytologic grading since histopathology will not be obtained 

• If cytologically high grade, expect lower response rate 

• Systemic therapy is warranted for high grade MCTs 

• Perform regional lymph node cytology to confirm nonmetastatic prior to administering tigilanol tiglate. 

• Bandaging and Elizabethan collars are not recommended, as the dog’s licking helps remove necrotic tumor tissue from the site. 

• The treatment site is considered a “clean” wound, so antibiotics are likewise not commonly needed. 

• Consider previsit anti-anxiety and analgesic drugs and/or injectable sedation for treatment of very active or agitated patients. 

• Wear personal protective equipment including gloves, protective eye wear, and a lab coat or gown when handling and administering this product. 

• Caution is required during treatment to avoid accidental self-injection, which may cause severe wound formation. 

Clinical takeaways    Tigilanol tiglate is not for every case, but can be a viable nonsurgical option for the following cases:   

• Dogs with multiple low grade MCT  

• Dog whose owner whoelectsagainst surgery   

• Dogs with a tumor in a challenging location to obtain a complete surgical removal

   References 

1. McCafferty C. Affordable early detection test for canine lymphoma to hit the market. dvm360. January 27, 2025. Accessed December 3, 2025. https://www.dvm360.com/view/affordable-early-detection-test-for-canine-lymphoma-to-hit-the-market 
2. Connell D, Drake C, Michael H, Nascimento, Stuart S, Lyons H. Performance of IDEXX Cancer Dx testing for detection of lymphoma and corresponding phenotype in dogs. IDEXX. 2025. Accessed December 3, 2025. www.idexx.com/files/cancer-dx-white-paper-en-na.pdf 
3. Beaver LM, Strottner G, Klein MK. Response rate after administration of a single dose of doxorubicin in dogs with B-cell or T-cell lymphoma: 41 cases (2006-2008). J Am Vet Med Assoc. 2010;237(9):1052–1055. doi:10.2460/javma.237.9.1052 
4. Brodsky EM, Maudlin GN, Lachowicz JL, Post GS. Asparaginase and MOPP treatment of dogs with lymphoma. J Vet Intern Med. 2009;23(3):578–584. doi:10.1111/j.1939-1676.2009.0289.x 
5. Rebhun RB, Kent MS, Borrofka SAEB, Frazier S, Skorupski K, Rodriguez CO. CHOP chemotherapy for the treatment of canine multicentric T-cell lymphoma. Vet Comp Oncol. 2011;9(1):38–44. doi: 10.1111/j.1476-5829.2010.00230.x 
6. Musser ML, Clifford CA, Bergman PJ, et al. Randomised trial evaluating chemotherapy alone or chemotherapy and a novel monoclonal antibody for canine T-cell lymphoma: a multicentre US study. Vet Rec Open. 2022;9(1):e49. doi:10.1002/vro2.49 
7. Camus MS, Priest HL, Koehler JW, et al. Cytologic criteria for mast cell tumor grading in dogs with evaluation of clinical outcome. Vet Pathol. 2016;53(6):1117–1123. doi:10.1177/0300985816638721 
8. Scarpa F, Sabattini S, Bettini G. Cytological grading of canine cutaneous mast cell tumours. Vet Comp Oncol. 2016;14(3):245–251. doi:10.1111/vco.12090. 
9. Hanazono K, Fukumoto K, Endo Y, et al. Ultrasonographic findings related to prognosis in canine transitional cell carcinoma. Veterinary Radiology and Ultrasound. 2013;55(1):79–84. doi:10.1111/vru.12085 
10. Mochizuki H, Kennedy K, Shapiro SG, Breen M. BRAF mutations in canine cancers. PLoS One. 2015;10(6):e0129534.doi: 10.1371/journal.pone.0129534. 
11. Sadowski AR, Gardner HL, Borgatti, A, et al. Phase II study of the oral selective inhibitor of nuclear export (SINE) KPT-335 (verdinexor) in dogs with lymphoma. BMC Vet Res. 2018;14(1):250. doi:10.1186/s12917-018-1587-9 
12. Bergman PJ, Ogilvie GK, Powers BE. Monoclonal Antibody C219 Immunohistochemistry Against P-Glycoprotein: Sequential Analysis and Predictive Ability in Dogs With Lymphoma. J Vet Intern Med. 1996;10(6):354-359. doi:10.1111/j.1939-1676.1996.tb02080.x 
13. Vlodaver EM, Keating MK, Bidot WA, Bruyette DS, Rosenkrantz WS, et al. Open-label pilot study: Efficacy of verdinexor for naïve canine epitheliotropic cutaneous T-cell lymphoma. Vet Dermatol. 2024;35(1):536-546. doi:10.1111/vde.13280 
14. Grady JL, Gencher J, Adrianowycz S, Martinez-Romero G. Clinical remission of cutaneous lymphoma in a dog treated with verdinexor. J Am Anim Hosp Assoc. 2024;60(5):223-226. doi:10.5326/JAAHA-MS-7443 
15. Miller J, et al. Dose characterization of the investigational anticancer drug tigilanol tiglate (EBC-46) in the local treatment of canine mast cell tumors. Front Vet Sci. 2019;6:106. doi:10.3389/fvets.2019.00106 
16. Reddell P, De Ridder TR, Morton JM, et al. Wound formation, wound size, and progression of wound healing after intratumoral treatment of mast cell tumors in dogs with tigilanol tiglate. J Vet Intern Med. 2021;35(1):430-441. doi:10.1111/jvim.16009 
17. Jones PD, Campbell JE, Brown G, Johannes CM, Reddell P. Recurrence-free interval 12 months after local treatment of mast cell tumors in dogs using intratumoral injection of tigilanol tiglate. J Vet Intern Med. 2021;35(1):451–455. doi:10.1111/jvim.16018 
18. Musser ML,Jones PD,Goodson TL,Roof E,Johannes CM.Response to tigilanol tiglate in dogs with mast cell tumors. J Vet Intern Med. 2024; 38(6):3162-3169. doi:10.1111/jvim.17211 

https://www.dvm360.com/view/understanding-oncology-diagnostics-and-therapeutics _________________________________________________________________________________________ American Humane Society I Cold-Weather Pet Tips  People who live in areas experiencing cold weather and winter storms need to take extra precautions to keep their animals safe. Pets left to fend for themselves in cold weather are susceptible to injury and death. Here are some simple tips from American Humane:  Be Prepared 

• Plan ahead and pay attention to cold-weather warnings. 
• Unless significant power outages are experienced, most cold-weather episodes and winter storms are “shelter in place” events, so pet care needs should be planned for in the home. Keep your pet preparedness kit well-stocked and ready — in a winter storm, you may not be able to leave your home for several days. 
• Leave your pets’ coats a little longer in the winter to provide more warmth. That summer “short cut” from your groomer should be avoided during cold weather. If you have short-haired breeds, consider getting them a coat or sweater that covers them from neck to tail and around the abdomen. 

Winter Pet Care 

• When you bathe your dogs in cold weather, make sure they are completely dry before taking them outside for a romp or walk. 
• When walking your dogs during bad weather, keep them on leash. It’s easier for a dog to become lost in winter storm conditions — more dogs are lost during the winter than during any other season. (And don’t forget to microchip and put ID tags on your dogs and cats!) 
• Leash your pets if you have frozen ponds, lakes or rivers nearby, as loose pets can break through ice and quickly succumb to hypothermia before trained ice-rescue personnel can arrive. Never try an ice rescue of a pet yourself — leave that to trained professionals. 
• When you are working on housebreaking your new puppy, remember that puppies are more susceptible to cold than are adult dogs. In cold conditions or bad weather, you may need to opt for paper training your new pet rather than taking the pup outside. 
• Keep your pets inside, both during the day and night. Just because they have fur doesn’t mean they can withstand cold temperatures. 
• If dogs are left outside, they should have a draft-free shelter large enough to stand and turn around in, yet small enough to retain body heat. Use a layer of straw or other bedding material to help insulate them against the cold. Make sure the entrance to the shelter faces away from the direction of incoming wind and snow. 
• Keep your cats indoors. Cats can freeze in cold weather without shelter. Sometimes cats left outdoors in cold weather seek shelter and heat under the hoods of automobiles and are injured or killed when the ignition is turned on. Banging loudly on the hood of your car a few times before starting the engine will help avoid a tragic situation. (This is true for wild animals in cold weather as well). 
• When taking your pets out for a bathroom break, stay with them. If it’s too cold for you to stand outside, it is probably also too cold for your pets. 
• Level Up Your Pet Parenting Skills With Our Free Guide! 
• Unleash the ultimate pet parenting guide! Sign up now to receive our exclusive guide filled with expert advice from American Humane Society’s animal care and veterinary specialists. Discover essential training techniques, vital pet care tips, and much more. 

Precautions for Outdoor Pets 

• If your pet is outside during cold weather: 
• Remember that staying warm requires extra calories. Outdoor animals typically need more calories in the winter, so feed them accordingly when the temperature drops. Talk to your veterinarian for advice on proper diet. 
• Watch your pet’s outside fresh-water bowl. If it is not heated, you may need to refresh it more often as it freezes in cold weather. 
• Salt and de-icers: Many pets like to go outside to romp and stomp in the snow, but many people use powerful salt and chemicals on their sidewalks to combat ice buildup. Thoroughly clean your pets’ paws, legs and abdomen after they have been outside, to prevent ingestion of toxic substances and to prevent their pads from becoming dry and irritated. Signs of toxic ingestion include excessive drooling, vomiting and depression. 
• Ice and snow: When you let your pets in from a walk or a romp outside, make sure to wipe their paws and undersides — get those ice balls off as soon as possible, as they can cause frostbite. After being outside, check your pets’ paws, ears and tail for frostbite. Frostbitten skin usually appears pale or gray and can be treated by wrapping the area in a dry towel to gradually warm the area. Check with your veterinarian if you suspect frostbite. 
• Use nontoxic antifreeze. Antifreeze is great-tasting to pets, but even a very small amount ingested can be deadly. Look for “safe” nontoxic antifreeze, consider using products that contain propylene glycol rather than ethylene glycol, and make sure all spills are cleaned up immediately and thoroughly. Contact your veterinarian immediately if you suspect your pets have ingested any antifreeze! 

_______________________________________________________________________________________ AVMA NEWS I American Bar Association highlight link between domestic violence, animal cruelty  Experts say the biggest red flag of potential animal abuse is inconsistent medical history  Published on November 19, 2025  The AVMA and the American Bar Association (ABA) have partnered to draw attention to the link between violence against people and animals.   Dr. Amanda Bisol, who represents District 1 on the AVMA Board of Directors and has a law degree, and Dr. Kendall Houlihan, associate director in the AVMA Animal Welfare Division, participated in a webinar, “Protecting People and Pets from Domestic Violence,” on October 22.   Spotting the signs  Dr. Bisol highlighted the importance of recognizing signs of animal maltreatment in clinical settings, such as unexplained injuries and a general lack of care or history that “just doesn’t add up.”   “The biggest red flag is an inconsistent [medical] history,” Dr. Bisol said. Another sign that is not as common are multiple injuries on the same animal that are different ages—for example, if an X-ray of a new fracture shows a healing fracture.   It’s important to be aware of how domestic violence and animal maltreatment can be interconnected, Dr. Bisol said, because sometimes, veterinarians may be the only ones to see the potential signs of an issue in a home. She also urged documenting a suspicious case with additional detail, including pictures, as such veterinary records may be valuable evidence if the case is investigated.   The sessions include an overview of how to identify signs of domestic violence and animal abuse or neglect and show how the two may be connected. Presenters also discuss how to access resources that support survivor decision-making and how to foster collaboration with local organizations and agencies that can help protect both survivors and their pets.  Collaborative effort  This collaboration between the AVMA and ABA comes after the law association adopted Resolution 504 earlier this year, urging all levels of government “to enact legislation and/or support judicial processes that protect individuals by protecting their pets in family law and civil restraining order proceedings.”  “The aim of this collaboration is to highlight the roles and responsibilities of different professionals and how we may more effectively interact with and support each other and our communities,” said Dr. Houlihan.   AVMA policy on “Animal Abuse and Animal Neglect” states that prompt disclosure of abuse is necessary to protect the health and welfare of animals and people.  While disclosure is important, “it is not the veterinarian’s task to determine if the maltreatment meets the enumerated elements of a crime; this is the duty of the investigating authority and the criminal justice system,” according to the AVMA’s “The Veterinarian’s Framework for Identification and Response to Suspected or Known Animal Maltreatment,” a free resource for veterinary professionals.  Veterinary social workers are uniquely dedicated to tending to the human needs that arise from relationships between humans and animals. Accordingly, Dr. Bethanie Poe, associate director of education and training for the University of Tennessee’s Center for Veterinary Social Work, also provided her expertise to the sessions.  Guiding future efforts  Animal cruelty has historically been considered an isolated issue that is not indicative of other violence. However, “recent research shows a well-documented link that it is a predictive or co-occurring crime with violence against humans (including intimate partners, children, and elders) and is associated with other types of violent offenses,” according to a 2021 Federal Bureau of Investigation Law Enforcement Bulletin. “Increased awareness of this linkage and a collaborative approach to these investigations strengthens the identification and reduction of such crimes.”  One result of the growing awareness of the link between animal and personal violence is greater consideration of what to do with a pet when the owner enters a domestic violence shelter.  For example, a paper published in the May 2024 issue of JAVMA described the creation of a safekeeping program for pets owned by domestic violence victims.   Dr. Hillary L. Pearce and others found that involving at least one veterinary practice was integral, “as most pets entering the program needed vaccination, testing for infectious disease, and/or parasiticide prevention before being placed into foster homes. The veterinary practice also served as a crucial temporary holding facility until pets could be matched into suitable foster homes.”  Recognizing that a variety of professionals engage with people and pets affected by domestic violence, future collaborations may add the perspectives of law enforcement and judges, who also work to support the human-animal bond in challenging circumstances.  https://www.avma.org/news/avma-american-bar-association-highlight-link-between-domestic-violence-animal-cruelty?utm_source=delivra&utm_medium=email&utm_campaign=todays-headlines-news  ___________________________________________________________________________________________________________ AVMA I News Normalize pet nutrition conversations at every veterinary visit  Purina handbook explores pet nutrition across the lifespan with proactive and practical recommendations  Published on November 17, 2025  As pet obesity rates continue to climb nationwide, nutrition is top of mind for pet owners and veterinarians alike.  The Purina Institute Handbook of Canine and Feline Well-Pet Nutrition, launched in August, provides evidence-based recommendations for veterinary care teams to help them prioritize pet nutrition in practice. The handbook is available for free with a sign-up for scientific communications from the institute.  The handbook cites a May 2023 Purina Institute survey, which showed 96% of pet owners said they trust their veterinarian for pet nutrition advice, but only 22% of veterinary professionals have proactive conversations about nutrition at most visits.  “Nutrition also brings the pet pleasure, positively reinforces the human-animal bond, and helps owners express love to their pets,” according to the introduction. “As we continue to recognize the integral role that pets play in our lives, it is essential to acknowledge the importance of proper nutrition in ensuring their health and longevity.”  Pet nutrition  Developed with contributions from 54 experts across 20 countries, the 322-page handbook covers nutrient fundamentals in small animals, specialized nutrition guidance by life stage, proactive nutrition recommendations for various health benefits, and other practical tools.   For example, Dr. Yuki Okada, a board-certified veterinary nutritionist in San Francisco, in the guide calls protein “undoubtedly the most critical macronutrient in the nutrition of both dogs and cats, serving as the primary source of amino acids and nitrogen for various physiological functions.”   The recommended protein intake is approximately 4 g/kg of body weight for senior dogs and about 5.2 g/kg for senior cats, according to the handbook, unless kidney disease necessitates certain restrictions.   Cats, as obligate carnivores, have significantly higher protein needs than dogs to maintain a constant state of gluconeogenesis that meets energy demands.   And senior pets may need up to 50% more protein than younger adults to counteract age-related muscle loss.  Overall, geriatric pets experience physical, functional, and metabolic changes that are still amenable to nutritional intervention to improve health and quality of life. A cohesive framework of nutritional prioritization and planning can aid in managing comorbidities in geriatric pets, according to the guide.   The section on proactive strategies covers the impact nutrition has on everything from oral and gastrointestinal health to joint, behavioral, and urinary health.   In addition, a table of ingredients commonly found in dental diets, treats, and chews, such as folic acid or polyunsaturated fats, shows the respective modes of action.   Client conversations  The handbook calls for veterinary care teams to have “a well-stocked communication skill toolkit” on hand to equip conversations with clients about pet nutrition.  Talk model   “Clients want to be partners in their pet’s veterinary care,” the handbook states. “Clients that understand the beneficial outcome for their pet (the ‘why’ behind recommendations) are more likely to adhere to plans of care.”  Or, talking about pets’ skin and coat health, an overall health indicator, is also a great conversation starter.  The section also addresses some common communication challenges and how to navigate them, including client resistance, skepticism, and the perception that a discussion on pet foods is driven by financial motivations and wanting to “make a sale.”   Veterinary professionals need to be prepared to confront and correct misinformation, as well as disinformation, differentiated as “false or incorrect information that is shared with an underlying intent to mislead.”  Care teams can counter misinformation by proactively discussing and providing resources on common nutritional myths. This is known as inoculation or “prebunking” with “cognitive antibodies,” with the aim of making pet owners more resilient to nutritional misinformation in the future.  Practical tools  Beyond nutritional science, the handbook offers 25 “Practical Tools,” including a fecal scoring chart with pictures and descriptions of different stools.  It also includes guidance on feeding “finicky” felines, managing cat allergens through nutrition, and selecting products marketed as supplements, as well as scoring charts for assessing body and muscle condition.   “It has been reported that pet owners tend to underestimate the body condition of their pet, emphasizing the importance of equipping every team member to perform and teach body condition scoring (BCS) and muscle condition scoring (MCS) at each visit,” writes Ashley Self, assistant director of veterinary nutrition at Texas A&M University College of Veterinary Medicine and Biomedical Sciences. “By involving the owners in the process of obtaining a body weight and estimating BCS and MCS, veterinary teams can identify trends that support proactive management while also enhancing the pet owner’s understanding of what constitutes a healthy body weight, BCS, and MCS.”   Veterinarians should also educate pet owners on available tools like wearable devices, litter box monitoring systems, and mobile applications that support at-home monitoring for more proactive and preventive care.  “Nutritional science has evolved significantly, and there are many facets to consider in a well-pet diet—not just from the pet’s perspective, such as life stage, activity level, and body condition, but also the owner’s perspective—their lifestyle, budget, and preferences,” said Natalia Wagemans, MD, the institute’s global head, in an August 28 press release. “This resource simplifies the process of making informed recommendations and can be a vital tool for veterinary professionals to both facilitate nutrition conversations with their clients and provide informed responses to questions.”  https://www.avma.org/news/normalize-pet-nutrition-conversations-every-veterinary-visit?utm_source=delivra&utm_medium=email&utm_campaign=todays-headlines-news  ____________________________________________________________________________________________________________ AVMA News I FDA reminds pet food makers that raw ingredients pose risk of exposure to H5N1  Published on November 14, 2025  Federal agencies are tightening regulations on raw pet food ingredients due to the risk of highly pathogenic avian influenza (type A H5N1) transmission.   Recent investigations have pointed to raw meat, specifically poultry, and unpasteurized milk as a source of infection for cats, both domestic and wild, which can experience severe illness or death from infection with the virus.   Dogs can also contract H5N1, although they usually exhibit mild clinical signs and low mortality.   “During the fall migratory season, H5N1 detections typically increase throughout the United States in wild birds, with potential spread to commercial and backyard poultry flocks,” according to the Food and Drug Administration (FDA) Center for Veterinary Medicine.   Suspected or verified sources of  highly pathogenic avian influenza type A H5N1 infecting cats include unpasteurized cow’s milk and raw poultry products.  With that in mind, on September 30, the agency issued a reminder to pet food manufacturers that H5N1 is a “known or reasonably foreseeable hazard” when using uncooked or unpasteurized ingredients.   Under the agency’s Food Safety Modernization Act Preventive Controls for Animal Food requirements, animal food businesses must conduct a reanalysis of their food safety plan when the FDA determines it is necessary to respond to new hazards and developments in scientific understanding.   Earlier this year, the FDA determined that food safety plans of manufacturers that specifically use uncooked or unpasteurized materials from poultry or cattle should include H5N1 as a potential hazard and implement preventive controls as needed. This could include seeking ingredients from healthy flocks or herds, taking processing steps such as heat treatment, or implementing a supply chain–applied control to provide assurance that ingredients used in animal food do not come from H5N1-infected animals.   “Manufacturers that implement a preventive control for the H5N1 hazard as a result of their reanalysis will be taking an important step toward protecting cat and dog health and helping to prevent spread of H5N1,” according to the FDA.  _______________________________________________________________________________________________________________________ Taylor & Francis Online I Serum Onconeural Antibodies in Dogs and Cats for Early Diagnosis of Cancer  Marianna Agassandian & Khristofor Agassandian  Published online: November 12, 2025  Abstract  Cancer is one of the leading causes of death in dogs and cats worldwide, and effective early detection techniques and reliable therapies are still lacking. Given the high demand for early cancer detection and differentiation in veterinary diagnostics, we developed and validated a new diagnostic approach to assess onconeural antibodies, also known as high-risk antibodies, in dog and cat blood serum samples. We determined the presence of systemic onconeural/high-risk (ONHR) antibodies, their suitability for early cancer diagnostics, and the feasibility of differentiating various malignancies. Our results identified several ONHR antibodies in 0.1 mL of specimens by the immunoblot-based technique, which was confirmed by indirect immunofluorescence assay. The diagnostic performance for detecting identified antibodies has demonstrated >95% sensitivity in dogs, >93% sensitivity in cats, as well as >97% specificity in dogs, and >95% specificity in cats. Thus, our data provide the first proof-of-principle that onconeural antibodies can be detected in dogs and cats, and their identification in serum might serve as a new tool for early cancer diagnosis.  Introduction  Malignant tumors in companion animals are a significant problem affecting the lives and well-being of pets and their owners. According to the Veterinary Cancer Society, cancer is the leading cause of death in 47% of dogs, especially elderly dogs, and 32% of cats.Citation1 Dogs develop cancer at almost the same rate as humans.Citation2 Cancer detection at the earliest stage may significantly improve the efficacy of the treatment and survival. Sensitive and specific methods for cancer screening can reduce mortality and improve the quality of life of affected animals.  Recently, two advanced techniques adapted from human cancer diagnostics have been implemented into veterinary medicine. The OncoK9 “liquid biopsy”, based on next-generation sequencing, could only differentiate hematological malignancies, required large blood volumes, was costly, and was discontinued from commercial use.Citation3  The second, Nu.Q test, measures plasma nucleosome concentration to predict certain cancers but provides only positive/negative results and can be provoked by inflammation, trauma, or other diseases.Citation4  To address these diagnostic limitations, we focused on antibody biomarkers, widely used in human medicineCitation5 but still limited in veterinary diagnostics due to a lack of development and standardization.Citation6–11 Canine and human cancers share biological similarities,Citation12 making this approach promising. We investigated onconeural antibodies, produced against neuronal proteins aberrantly expressed in tumor cells. These antibodies are linked to paraneoplastic neurological syndromes (PNS), which may precede cancer diagnosis.Citation13 Although not always directly pathogenic, they are valuable diagnostic markers.Citation14  Onconeural antibodies target intracellular or extracellular (membrane-bound) neuronal or glial proteins. Antibodies against intracellular proteins are more specific for malignancy rather than neurological syndromes and considered “high-risk”,Citation14,Citation15 while extracellular-directed antibodies are more closely tied to neurological diseases.Citation16 Sometimes, multiple antibodies coexist and are associated with the same cancer or PNS.Citation17 Paraneoplastic disorders are diagnosed in human patients with cancer, but there is a lack of knowledge about these diseases in animals. Even though these syndromes have been reported in dogs and cats, these diseases are usually diagnosed too late after the identification of cancer.  Since ONHR antibody formation usually precedes cancer, its early detection can predict malignancy before clinical symptoms, aiding timely treatmentCitation18–21 and better outcomes for pets.Citation22–24 Thus, serological detection of ONHR antibodies represents a convenient diagnostic method for early cancer detection and differentiation.  Depending on the type of malignancy, tumor cells may express intracellular proteins/antigens such as amphiphysin, CV2/CRMP5, Ri/NOVA1, Yo/CDR2, Hu/ELAV, recoverin, SOX1, titin, ZIC4, GAD65, and Tr/DNER that are normally restricted to the nervous system.Citation25–35 These antigens can induce specific antibody formation before tumors are symptomatic. Altered expression, mutations, or posttranslational modifications can create neoantigens, provoking immune responses.Citation36  As illustrated in many studies, between 50 and 90% of tumor-associated proteins/antigens in the human body acquire a variety of modifications that alter immunologic processing and presentation.Citation37 Thus, the modified self-antigens and neoantigens can be recognized as non-self-antigens by the immune system and promote onconeural antibody formation in the blood of patients with different types of tumors and have the potential to be an early sign of cancer. According to the literature, ONHR antibodies were detected in more than 90% of cases with underlying cancer within a few years of the study.Citation38  Unfortunately, in veterinary medicine, only a few antibodies to neuronal proteins have been identified.Citation39–45 In our study, we validated ONHR antibodies in sera of cancer-bearing dogs and cats, confirming their stability and strong association with malignancies. These findings support their use as novel, noninvasive biomarkers for early cancer detection and malignancy-associated neurological diseases in pets.  Materials and Methods  Ethics Statement  Ethical approval was not required for this study, as it used de-identified residual serum samples submitted to Pet Preferred Diagnostics for research purposes and after routine diagnostics, with no additional collection or animal interventions.  Inclusion Criteria  The validation study was conducted on a total of 202 dogs and 50 cats, including 76 presumably healthy dogs and 20 presumably healthy cats with medical records from participating veterinary clinics and the National Institute of Health blood bank. The records included patient information such as age, sex, breed, neuter status, clinical history, and examination details.  Serum samples were collected from dogs and cats with confirmed or suspected malignancies at the time of validation, as well as animals with specific neurological symptoms. Sera obtained from presumably healthy dogs and cats, based on physical examination and clinical history, were also included in the validation study. Animals with conditions such as chronic infections were excluded from this study.   Animal Samples  Serum samples (0.05–0.5 mL) from animals (dogs and cats) with confirmed, suspected cancer, and presumably healthy were prepared from blood using VACUETTE tubes with serum separator. After 30–45 minutes at room temperature (which allows blood to clot), the tubes containing the collected blood were centrifuged at 2000–2500 RPM for 20 minutes to separate the serum. Sera were then transferred to Eppendorf tubes labeled with the patient’s name and date of sample collection and shipped to Pet Preferred Diagnostics laboratory to be tested for the presence of onconeural antibodies.  Routine screening for the presence of ONHR antibodies such as anti-Hu, -Yo, -CV2, -Ri, -Tr, -ZIC4, -SOX1, -GAD65, -recoverin, -amphiphysin, and anti-titin (11 ONHR antibodies) was performed by immunoblot and confirmed by indirect immunofluorescence technique (IIFT) using monkey tissue slides.  Protein Sequence Comparison  UniProt Knowledgebase (UniProtKB) has been used for the analysis of ELAV/HuD (ELAV-like protein 4), CDR2/PCD17 (cerebellar degeneration-related protein 2), CRMP5/DPYSL5 (dihydropyrimidinase-related protein 5), NOVA1 (RNA binding protein), DNER/BET (Delta/Notch-like epidermal growth factor-related receptor), ZIC4 (Zinc finger protein), SOX1 (transcription factor protein), GAD65 (glutamate decarboxylase 2), RCVRN/RCV1 (recoverin/cancer-associated retinopathy protein), AMPH/BIN1 (amphiphysin/bridging integrator1/Myc box-dependent-interacting protein 1), and TTN (Titin/Connectin) human, canine, and feline protein sequences. Human, canine, and feline protein sequences were aligned using Clustal Multiple Sequence Alignment. A sequence similarity search query was submitted in the FASTA format.   Immunoblot-Based Assay  Serum samples from dogs and cats were tested using the commercial immunoblot kit (EUROLINE Neuronal Antigens Profile 72 (IgG), DL 1111–1601-72 G; Euroimmun, Lübeck, Germany). Immunoblots were performed on the EUROBlotOne system (Euroimmun). The nitrocellulose test strips with immobilized amphiphysin, CV2, Ri, Yo, Hu, recoverin, SOX1, titin, ZIC4, GAD65 and Tr antigens were incubated with patients’ serum according to the manufacturer’s instructions, modified and validated by our laboratory to adapt the test kit for veterinary diagnostics.  The strips were washed with a buffer provided in the kit and then incubated with the secondary alkaline-phosphatase conjugated goat anti-Canine IgG (SouthernBiotech, Birmingham, AL, USA) and goat anti-Cat (Bethyl Laboratories, Montgomery, TX, USA) antibodies. The onconeural antibodies in the serum bound to the related antigens were then visualized by NBT/BCIP substrate solution (nitroblue tetrazolium chloride/5-bromo-4chloro-3 indolylphosphate, Euroimmun). The intensity of binding of 11 ONHR antibodies was evaluated using EUROLineScan software (Euroimmun). An ONHR antibody band intensity value between 0 and 7 was considered negative or Class 0, between 8 and 14 was considered borderline or Class (+), between 15–35 and 36–70 as positive or Classes +, ++, and above 70 as strongly positive or Class +++. Strips with no added serum samples were used as negative controls.  Indirect Immunofluorescence Assay  The Neurology Mosaic 8 testing kit (Euroimmun, FA 1111–1005-8) is an indirect immunofluorescence assay used to confirm the presence of autoantibodies against eight targets associated with cancers and neurological diseases. This test detects antibodies against Hu, Yo, CV2, Ri, Tr, ZIC4, GAD65, and amphiphysin.   Serum samples were applied to the slides that were filled with BIOCHIPs – cerebellum and pancreatic sections collected from a monkey, according to the manufacturer’s instructions, and were modified and validated by our laboratory to adapt the test kit for veterinary diagnostics. Sera from a dog and a cat previously diagnosed with cancer were used as positive controls. A serum sample from a healthy dog or cat was included in each evaluation as the negative control. After incubation with diluted serum samples (1:10 to 1:100) for 30 min at room temperature, BIOCHIP slides were washed with phosphate-buffered saline/Tween (PBST) for 5 min and developed with secondary fluorescent-labeled antibodies (for dog samples: fluorescein isothiocyanate (FITC)-conjugated goat anti-Dog IgG, Euroimmun; for cat samples: FITC-conjugated goat anti-Cat IgG from Jackson ImmunoResearch Laboratories, West Grove, PA, USA). The BIOCHIP slides were then incubated for 30 min at room temperature and washed with PBST for at least 5 min. Immunofluorescent images were acquired with the EUROStar III Plus fluorescent microscope at ×20 and ×40. Each power field was captured in four quadrants using the same imaging technique. Serum samples from dogs and cats with positive results were retested with positive and negative controls to ensure the repeatability of the results.  Statistical Analysis  Sensitivity and specificity were determined as the fractions of true-positive results in the cancer-diagnosed/detected group and true-negative results in the control group, respectively, and calculated for results where borderline results were interpreted as negative. Confidence intervals (CIs) were determined to be 95% for all sensitivity and specificity calculations. Microsoft Excel (Microsoft Corporation, Redmond, WA, USA) and GraphPad Prism 10 (GraphPad, San Diego, CA, USA) online tools were used for statistical analyses.   https://www.tandfonline.com/doi/full/10.2147/VMRR.S537744#d1e278   ________________________________________________________________________________________________________________________ DVM360 – November 3, 2025  Feline diabetes mellitus: Advancements in treatment and the role of the veterinary team  Author(s)Ellen Carozza, LVT, VTS (CP-Feline)  Fact checked by: Caitlin McCafferty, Editor  Veterinary teams enhance feline diabetes management through personalized care, effective communication, and evolving treatment options for improved quality of life.  Feline diabetes mellitus (feline DM) has been recognized in veterinary medicine since the 1970s, with a significant increase in prevalence correlated with trends in feline obesity and sedentary lifestyles, particularly noted since the 1990s. While the veterinary field has managed feline diabetes for several decades, it was not until the early 2000s that synthetic long-acting insulin analogs such as glargine (Lantus;Sanofi) and detemir (Levemir;Novo Nordisk) became widely utilized. These formulations have contributed significantly to improved glycemic regulation and quality of life in diabetic feline patients.  In the last 5 years, further advancements have emerged with the introduction of oral hypoglycemic agents, notably the sodium-glucose cotransporter 2 (SGLT2) inhibitors bexagliflozin (Bexacat;Elanco) and velagliflozin (Senvelgo; Boehringer Ingelheim). However, current guidelines generally recommend that these agents be used only after initial management with injectable insulin, due to the potential for complications such as diabetic ketoacidosis if the patient is misclassified or poorly monitored.  Given the increasing complexity of available treatment options, it is imperative to evaluate each feline diabetic patient holistically, considering not only the pathophysiology of the disease but also the capacity of the caregiver and veterinary team to support ongoing disease management. Historically, feline DM was conceptualized primarily as an insulin-deficiency disorder; however, it is now widely understood to resemble human Type 2 diabetes, characterized by peripheral insulin resistance and progressive pancreatic beta-cell dysfunction.  Client communication and individualized care  Effective diabetes management begins with a thorough and empathetic conversation between the veterinary team and the pet caregiver. Diabetes mellitus is a chronic, multifactorial condition that necessitates sustained client education, regular monitoring, and collaborative decision-making. Many of the clinical signs, such as polyuria, polydipsia, weight loss, and lethargy, are non-specific and may be initially misattributed to other conditions. Thus, clear and early communication is critical for both diagnosis and ongoing care.   Each case must be approached individually, as clients vary widely in their financial capacity, emotional resilience, and physical ability to manage a diabetic cat. Some clients may be comfortable administering injectable medications, while others may have limitations—visual impairment, needle phobia, or handling difficulties with a reactive or fearful cat—that necessitate alternative treatment strategies. Identifying these barriers early can guide the development of realistic, personalized treatment plans.  The role of the veterinary team  Successful management of feline DM requires a coordinated, team-based approach. The client service representatives (CSRs) serve as the initial point of contact, often fielding inquiries from owners who may be unaware of the severity of their pet’s condition. Proper training enables CSRs to triage appropriately and escalate potential emergencies to the veterinary technical or clinical team when needed. Additionally, proactive scheduling of follow-up diagnostics and appointments by CSRs is essential for maintaining continuity of care.  Technicians play a critical role in diagnostics, client education, and treatment implementation. Their responsibilities include collecting comprehensive medical histories, performing initial assessments, obtaining diagnostic samples, and supporting the veterinarian in interpreting results. Importantly, technicians often act as the primary educators for at-home diabetes care, such as demonstrating glucose monitoring, explaining insulin administration, or helping troubleshoot challenges related to in-home care and medication compliance.  Veterinarians are responsible for guiding the clinical decision-making process, which includes identifying comorbidities that may influence insulin sensitivity, such as hyperthyroidism, pancreatitis, acromegaly, formulating diagnostic and treatment plans, and communicating prognosis and treatment goals. Tiered care options—ranging from ideal treatment protocols to financially or logistically constrained alternatives—should be presented without judgment, enabling clients to make informed decisions within their means.  Addressing barriers to compliance  Non-compliance in diabetic management is a common challenge and may stem from financial constraints, emotional stress, physical limitations, or misunderstanding of the disease. Rather than viewing non-compliance as failure, it should be approached as an opportunity for problem-solving and improved communication. Open-ended questioning—such as asking clients what they feel capable of managing—can uncover underlying barriers and lead to more sustainable care plans.  Client education should be iterative and reinforced at each visit. Educational materials, visual aids, and follow-up calls or check-ins can reinforce key concepts and provide ongoing support. Empowering clients to monitor their cat’s clinical signs and glucose levels at home increases their confidence and allows for early intervention if glycemic control deteriorates.  Quality of life and long-term management  An essential aspect of managing feline diabetes is the ongoing evaluation of quality of life—for both the patient and the caregiver. Clients should be counseled that while some cats may enter remission, others will require lifelong management. The emotional investment required should not be underestimated, and periodic reevaluation of the treatment plan may be necessary as the disease progresses or as other comorbid conditions develop.  Clear communication, shared decision-making, and flexibility in treatment approaches are vital. The veterinary team should set realistic expectations and remain responsive to changing circumstances, always centering the conversation on improving the cat’s quality of life and supporting the caregiver’s ability to provide care.  Conclusion  Feline diabetes is a dynamic and increasingly manageable condition, provided that the veterinary team and pet caregiver collaborate effectively. As treatment options evolve, so too must our strategies for communication, education, and client support. By embracing a team-based, client-centered approach, veterinary professionals can improve outcomes for diabetic cats and reduce the burden of care on their owners. Early intervention, continuous education, and a commitment to flexibility are key to successful, long-term management.  _____________________________________________________________________________________________________________________________________________

AVMA NEWS I Winter holiday pet safety  

November and December abounds with holiday celebrations, and nothing can spoil good cheer like an emergency trip to the veterinary clinic. These tips can help keep your winter holiday season from becoming not-so-happy—for your pet and for you. 

Plan in advance 

Make sure you know how to get to your 24/7 emergency veterinary clinic before there’s an emergency. Talk with your veterinarian in advance to find out where you would need to take your pet, and plan your travel route so you’re not trying to find your way when stressed. Always keep these numbers posted in an easy-to-find location in case of emergencies: 

• Your veterinarian’s clinic phone number 

• 24/7 emergency veterinary clinic (if different) 

• ASPCA Poison Control Center: 888-426-4435 

• Pet Poison Helpline: 855-764-7661 

Food 

Keep people food away from pets, and instruct everyone else to do the same. If you want to share holiday treats with your pets, make or buy treats formulated just for them. The following people foods are especially dangerous for pets: 

• Chocolate is an essential part of holidays for many people, but it is toxic to dogs and cats. It’s safest to consider all chocolate off limits for pets, even though the harm it can cause varies based on the type of chocolate, the size of your pet, and the amount eaten. 

• Other sweets and baked goods also should be kept out of reach. Not only are they often too rich for pets; they may contain the artificial sweetener xylitol, which has been linked to liver failure and death in dogs. 

• Table scraps – including gravy, sauces, dressing, and meat or poultry fat or skin – should be kept away from pets. During the holidays, when our own diets tend toward extra-rich foods, table scraps can be especially hard for pets to digest and can cause pancreatitis. Bones can cause choking or intestinal blockage. Plus, many foods that are healthy for people are poisonous to pets, including onions, raisins, and grapes. 

• Unbaked yeast dough can cause problems for pets, including painful gas and potentially dangerous bloating. 

Quick action can save lives. Signs that your pet may have eaten something they shouldn’t include sudden behavior changes, depression, pain, loss of appetite, vomiting, or diarrhea. If your pet has any of these signs, call your veterinarian or nearest veterinary emergency clinic immediately. You may also want to call the ASPCA Poison Control Center (888-426-4435) or the Pet Poison Helpline (855-764-7661); note that a fee may apply.  

Decorating 

Holiday plants, lights, candles, and other decorations can make the holidays festive, but they also pose risky temptations for our pets. 

• Ornaments can cause hazards for pets. Breakable ornaments can cause injuries, and swallowed ornaments can cause intestinal blockage or illness. Keep any ornaments, including those made from salt-based dough or other food-based materials, out of reach of pets. 

• Tinsel, ribbons, wreaths, and other decorative materials also can be tempting for pets to play with and eat. These items whether swallowed in whole or in part can cause choking or intestinal blockage. 

• Christmas trees can tip over if pets climb on them or try to play with the lights and ornaments. Consider tying your tree to the ceiling or a doorframe using fishing line to secure it. 

• Water additives for Christmas trees can be hazardous to your pets if swallowed. Avoid adding anything to the water for your tree if you have pets in the house. 

• Electric lights can cause burns when a curious pet chews the electrical cords. 

• Candles and oil lamps are attractive to pets as well as people. Never leave a pet alone in an area with a lit candle or lamp; it could result in a fire. 

• Flowers and festive plants can result in an emergency veterinary visit if your pet gets hold of them. Poinsettias, amaryllis, mistletoe, balsam, pine, cedar, and holly are among the common holiday plants that can be dangerous and even poisonous to pets who eat them. The ASPCA offers lists of plants that are toxic to dogs and cats. 

• Potpourris should be kept out of reach of inquisitive pets. Liquid potpourris pose risks because they contain essential oils and other ingredients that can severely damage your pet’s mouth, eyes and skin. Non-liquid potpourris containing flowers, leaves, bark, herbs, and/or spices could cause problems if eaten. 

Hosting parties and visitors 

Visitors can upset pets, as can the noise and excitement of holiday parties and any celebratory fireworks. Even pets that aren’t normally shy may become nervous in the hubbub that can accompany a holiday gathering. The following tips will reduce emotional stress on your pet and protect your guests from possible injury. 

• All pets should have access to a comfortable, quiet place indoors if they want to retreat. Make sure your pet has a room or crate somewhere away from the commotion, where your guests won’t follow, that your pet can go to anytime they want to get away. 

• Inform your guests ahead of time that you have pets or if other guests may be bringing pets to your house. Guests with allergies or weakened immune systems (due to pregnancy, disease, or medications/ treatments that suppress the immune system) need to be aware of the pets (especially exotic pets) in your home so they can take any needed precautions to protect themselves. 

• Guests with pets? If guests ask to bring their own pets and you don’t know how the pets will get along, you can either politely decline their request or plan to spend some time helping the pets to get to know each other, supervising their interactions, monitoring for signs of a problem, and taking action to avoid injuries to pets or people. 

• Pets that are nervous around visitors should be put it in another room or a crate with a favorite toy. If your pet is particularly upset by houseguests, talk to your veterinarian about possible solutions to this common problem. 

• Exotic pets make some people uncomfortable and may themselves be more easily stressed by gatherings. Keep exotic pets safely away from the holiday hubbub. 

• Watch the exits. Even if your pets are comfortable around guests, make sure you watch them closely, especially when people are entering or leaving your home. While you’re welcoming hungry guests and collecting coats, a four-legged family member may make a break for it out the door and become lost. 

• Identification tags and microchips reunite families. Make sure your pet has proper identification with your current contact information – particularly a microchip with registered up-to-date, information. That way, if your pet does sneak out, they’re more likely to be returned to you. If your pet isn’t already microchipped, talk to your veterinarian about the benefits of this simple procedure. 

• Clear the food from your table, counters and serving areas when you are done using them and make sure the trash gets put where your pet can’t reach it. A carcass or large quantity of meat sitting out on the carving table, or left in a trash container that is easily opened, could endanger your pet if eaten. Dispose of carcasses and bones – and anything used to wrap or tie the meat, such as strings, bags and packaging – in a covered, tightly secured trash bag placed in a closed trash container outdoors (or behind a closed, locked door). 

• Trash also should be cleared away where pets can’t reach it – especially sparkly ribbon and other packaging or decorative items that could be tempting for your pet to play with or eat. 

When you leave the house 

• Unplug decorations while you’re not around. Cats, dogs and other pets are often tempted to chew electrical cords. 

• Take out the trash to make sure your pets can’t get to it, especially if it contains any food or food scraps. 

Holiday travel 

Whether you take your pets with you or leave them behind, take these precautions to safeguard them whenever you’re traveling. Learn more about traveling with pets. 

• Interstate and international travel regulations require any pet you bring with you to have a health certificate from your veterinarian—even if you are traveling by car. Learn the requirements for any states or countries you will visit or pass through, and schedule an appointment with your veterinarian to get the needed certificate within the timeframes required by those destinations. (Even Santa’s reindeer need to get health certificates for their annual flight around the world!) 

• Pets in vehicles should always be safely restrained and should never be left alone in the car in any weather. Proper restraint means using a secure harness or a carrier, placed in a location clear of airbags. Never transport your pet in the bed of a truck. 

• If you’re traveling by air and considering bringing your pet with you, talk with your veterinarian first. Certain pets, such as short-nosed dogs and cats, may have difficulty with air travel. Your veterinarian is the best person to advise you regarding your own pet’s ability to travel. 

• Pack for your pet as well as yourself if you’re going to travel together. In addition to your pet’s food and medications, this includes bringing copies of their medical records, information to help identify your pet if they become lost, first aid supplies, and other items. Refer to our Traveling with Your Pet FAQ for a more complete list. 

• Boarding your dog while you travel? Talk with your veterinarian to find out whether and how to protect your pet from canine flu and other contagious diseases, and to make sure your pet is up-to-date on vaccines. 

______________________________________________________________________________________________________________________________________________ AVMA I News – Why persistence pays off when it comes to dietary management of chronic enteropathy patients – October 20, 2025 Prescribing therapeutic diets involves not only evaluating ingredients, but also strong client communication  Story by Malinda Larkin  If a patient is vomiting, has diarrhea, or is showing other gastrointestinal (GI) clinical signs, dietary management should automatically be on the table, says Dr. Adam Rudinsky, associate professor in the Department of Veterinary Clinical Sciences at The Ohio State University College of Veterinary Medicine.   He runs a laboratory dedicated to researching chronic enteropathies, pancreatic and hepatic disease, and intestinal microbiome. Dr. Rudinsky will be the first to acknowledge that getting owners to switch diets can be difficult.   “A diet switch is like a personal affront to people,” Dr. Rudinsky said. “A lot of their self worth, in terms of that animal, is tied up in the diet that they feed them. So, it can be a challenging discussion, particularly when you have a busy schedule.”   Taking a comprehensive diet history and making a purposeful diet selection are the keys to success when it comes to a nutritional management strategy, says Dr. Adam Rudinsky, associate professor in the Department of Veterinary Clinical Sciences at The Ohio State University College of Veterinary Medicine. He gave a lecture on the topic at the 2025 American Animal Hospital Association annual conference.   But he maintains it’s still worth the time and effort. He and Dr. Harry Cridge, associate professor of small animal internal medicine at Michigan State University College of Veterinary Medicine, each gave presentations on nutrition at the 2025 American Animal Hospital Association CON, held September 11-13 in Chicago. Both are board-certified specialists in small animal internal medicine.   Dietary selection   When considering a dietary management strategy, after taking a diet history, Dr. Rudinsky recommends asking these questions:  

• What is the duration of clinical signs—acute or chronic?  

• Where are the clinical signs localized? Stomach? Small or large bowel?  

• Are the clinical signs consistent with a specific disease process, such as pancreatitis or parvovirus?  

If the diagnosis warrants, a diet trial can be the first step, even before a biopsy or other invasive diagnostic procedure. Why? “Because many patients will respond to it and it’s cost effective,” Dr. Cridge said.   Dr. Rudinsky outlined five main diet categories for dogs and cats with acute or chronic GI clinical signs:  

• Highly digestible or low-residue diets: These diets take the work off the GI tract by requiring less digestive effort. Dr. Rudinsky uses these diets for dogs and cats that are underweight due to vomiting, mild small intestine disease, or acute GI disease because of their nutritional density.  

• Novel or limited-ingredient diets: Often associated with use in chronic GI disorders, especially small or large bowel disease, these diets can also help with food allergies. However, Dr. Rudinsky says the prevalence of food intolerance appears to be much higher than the true food allergy, as most animals are responding to the antigen load. “If you continue to feed a diet that is too rich or varied, you can get those responses frequently that appear as a chronic condition,” he said. When selecting a limited-ingredient diet, he advises choosing one with only a single carbohydrate and a single protein source in the ingredient list, both of which are ideally novel to the patient.  

• Hydrolyzed diets: These diets undergo hydrolysis processing to reduce allergenicity and antigenicity by altering macronutrient structure. Typically, they are highly digestible and have a reduced fiber content. Often these are a mainstay for chronic GI symptoms, such as pancreatitis in cats and small bowel disease in dogs and cats. Specifically, Dr. Rudinsky said, “The more I have a vomiter … or a small bowel diarrhea case, I love a hydrolyzed diet.”  

• Low-fat diets: These are diets with fat content generally in the range of less than 3 grams of fat per 100 kilocalories. More recently, fat content has been identified as an important component in the management of some canine GI diseases, especially pancreatitis, GI motility issues, or mixed bowel diarrhea cases, Dr. Rudinsky said. This doesn’t appear to be an issue for cats. However, “for dogs, if you use an easily digestible diet, you might as well use one that is low fat too,” he added.  

• Fiber-enriched diets: Fiber is added to diets for multiple reasons, but especially diarrhea and large bowel disease in both dogs and cats. The fiber type and source will influence the type of effect that is seen in the patient. The benefits of soluble and insoluble fiber, besides helping with diarrhea (soluble) or constipation (insoluble) include fermentation, production of volatile fatty acids, benefits to enterocyte health, augmentation of the microbiota, as well as alterations in gut motility and passage of GI luminal contents.  

When first getting started, Dr. Rudinsky recommends looking at hydrolyzed, novel protein, or easily digestible diets for cats. “Cats maintain the same response rate with easy digestible diets that they do with hydrolyzed and novel ingredient diets, but dogs do not,” he said, so only start with hydrolyzed or novel ingredient diets for dogs.   Dr. Harry Cridge, associate professor of small animal internal medicine at Michigan State University College of Veterinary Medicine, says he uses soluble fiber to control diarrhea and insoluble fiber to control constipation.    Also important to note is that even among a particular diet category, options can vary by ingredient list, fiber content, fat content, and more. For example, Dr. Cridge says elimination diets differ in more than just their protein. He recommends using product guides for up-to-date nutrient compositions, including looking at dietary fat and fiber content.   Both Drs. Rudinsky and Cridge suggest looking at the global nutrient profile of diets when evaluating macronutrient diet choices. Do not focus on percent as fed, which doesn’t take into account water content and other features of the diet, but rather look at grams per 100 kcal, Dr. Rudinsky said.   This information may not always be on the bag. In that case, they recommend using Tuft University Cummings School of Veterinary Medicine’s Clinical Nutrition Service Nutrient Calculator or product guides to help with comparing nutrients between diets.   Dedication pays   Recent research reaffirms the importance of purposeful nutritional management, especially for patients with chronic enteropathies.   A retrospective paper published this past May in the Journal of Veterinary Internal Medicine (JVIM) looked at 81 dogs with chronic enteropathy. Among those in which the only therapeutic change was a hydrolyzed or other alternative diet, 88% (14 of 16) had a decreased stool‐consistency score and 70% (16 of 23) saw a 69% reduction in their total Canine Inflammatory Bowel Disease Activity Index score.   Another study, published in the September-October 2024 issue of JVIM, followed 60 dogs with chronic inflammatory enteropathy for two years. The initial dietary response rate was about 45%, but over time, 73% of them ended up being diet responsive and able to come off modulators.   “Giving more evidence that even if you don’t get that initial dietary response, diet is still a fundamental component, because your ability to minimize medications later on is going to be super useful,” Dr. Rudinsky said.   Finally, he emphasized the importance of taking a complete diet history. A study out of the University of Zurich, published in 2022 in the journal Animals, found that dietary information gained from referring veterinarians and owners was often incomplete.   Among these dogs presenting to the university’s GI and internal medicine service, no dog had received more than one previous diet trial for chronic GI signs.   After prescribing all of the dogs a new diet, 58% had an initial dietary response. Then the researchers convinced all the owners with a dog that didn’t respond to switch to yet another diet, and those dogs saw a 66% dietary response rate. The researchers did this again and had a 44% dietary response rate for owners that had switched a third time.   “If you add those percentages up … they were able to drive their response rate up in chronic enteropathy animals up to 85% or 86%. So that is really powerful, especially if you think of those dogs that we’ve managed sometimes with super bad prednisone effects or other issues with chronic medications (to correct that).”   “A lot of us intuitively know this, but we’re so thankful if an owner even does one diet switch,” Dr. Rudinsky said. “Don’t be afraid to ask them to switch again if first switch isn’t working.”   So, when to switch? Dr. Rudinsky says, “If you have not seen a response in two weeks, you can abandon ship and switch. If you see a partial response at that two-week mark, then you want to go out to about four weeks.”   Dr. Cridge says two weeks for him, too, and then he’ll move onto another diet for canine patients. “I don’t push owners to try a diet for too long because that’s when they want to give up and try something else,” he said. For cats, he acknowledges the challenge is getting them to try the diet in the first place.   Another issue Dr. Rudinsky has noticed, beyond not convincing an owner to do a diet trial, is getting them to accept the cost of the new diet because many of them may be more expensive than what they are currently feeding their pet.   Finally, Dr. Cridge recommended referring patients to a board-certified veterinary nutritionist when there is a refractory case of chronic enteropathy or protein-losing enteropathy (PLE), presence of concurrent diseases, picky dogs that may need a home-cooked diet, or when owners wish to make a home-cooked diet.   “Nutritionists are invaluable resources, especially for refractory chronic enteropathy and PLE dogs and often will provide remote consultations directly,” he said.   _______________________________________________________________________________________________________________________________ Frontiers Veterinary Science – October 14, 2025  Sec. Veterinary Imaging Volume 12 – 2025 | https://doi.org/10.3389/fvets.2025.1655498   Seungeun Lee, Yoojin An, Yoonju Choi, Sungsoo Kim, Kichang Lee, Hakyoung Yoon  Introduction: Urethral wall thickness is a potential indicator of pathological changes in the feline lower urinary tract. However, reference values for total urethral thickness in cats have not been established. This study aimed to develop ultrasonographic reference ranges for total urethral thickness in clinically normal cats and to evaluate the effects of breed, sex, neutering status, body weight, and bladder volume. We further compared urethral thickness between healthy cats and those presenting with lower urinary tract signs (LUTS) and determined a diagnostic cutoff value.  Methods: A total of 302 cats were retrospectively analyzed in a multicenter study. Measurements were obtained from mid-sagittal ultrasonographic images at the level cranial to the pelvic symphysis.  Results: In clinically normal cats (n = 240), mean total urethral thickness was 2.20 ± 0.26 mm, with no significant influence of sex, breed, body weight, or bladder volume. Cats with LUTS (n = 62) demonstrated significantly greater urethral thickness (2.75 ± 0.51 mm, p < 0.001). Multivariable analysis identified LUTS as the strongest independent predictor of increased urethral thickness. Receiver operating characteristic analysis yielded an area under the curve of 0.859, confirmed by bootstrap validation (bias-corrected AUC = 0.858; 95% CI: 0.7840.918). A diagnostic cutoff of 2.49 mm achieved 76% sensitivity and 88% specificity.  Discussion: These findings establish ultrasonographic reference ranges for feline urethral thickness and propose a clinically useful threshold for detecting urethral abnormalities. Ultrasonography may therefore provide a reliable, non-invasive tool for evaluating urethral pathology in cats. 

1 Introduction 

Feline idiopathic cystitis is the most common cause of feline lower urinary tract disease (FLUTD) and is often associated with urethral obstruction resulting from urethral inflammation, muscular spasms, intraluminal plug formation, or neurological dysfunction (1). Urethritis and urethral neoplasia, including urothelial carcinoma, can also manifest as diffuse wall thickening on ultrasonographic imaging (2, 3), thereby contributing to urethral outflow resistance. Consequently, urethral thickness may represent a valuable parameter for assessing urethral disease.  Although urethritis has historically been considered rare in cats (3), this assumption may reflect underdiagnosis due to the limited use of definitive diagnostic procedures. Urethral biopsy and fine-needle aspiration, which are considered confirmatory, are not routinely performed because of their technical difficulty, invasiveness, and associated risks, including hematuria, transient urinary incontinence, and urethral laceration (4–6). As a result, urethral inflammation may remain undetected or be misclassified as another lower urinary tract disorder.  Necropsy findings in cats that did not respond to treatment for urethral obstruction have revealed marked inflammation in both the urethra and bladder (7). Furthermore, in cats with idiopathic cystitis, obstruction may arise from functional changes such as inflammation-induced spasm and edema rather than from a true mechanical blockage (7). Collectively, these findings suggest that urethritis may constitute a more common and underrecognized component of FLUTD than previously thought.  Computed tomography (CT) and magnetic resonance imaging (MRI) offer the advantage of complete urethral visualization and allow detection of pelvic soft tissue abnormalities. However, their application is constrained by high cost, the need for general anesthesia, and prolonged image acquisition times (8–10). Additionally, accurate evaluation frequently requires multiplanar reconstruction of thin-slice images (11).  Cystourethroscopy is a valuable diagnostic tool for evaluating feline lower urinary tract disorders because it allows direct visualization of the urethra and adjacent structures. However, its use is limited by the need for general anesthesia, specialized equipment, and the risk of complications such as hemorrhage, infection, or iatrogenic injury (6, 12, 13). In contrast, ultrasonography is a non-invasive, cost-effective modality that does not require anesthesia. It enables rapid assessment while avoiding exposure to ionizing radiation (10). Ultrasonography is particularly useful for evaluating the proximal urethra in females and the prostatic urethra in males (14).  Despite these advantages, no previous studies have established reference ranges for total urethral thickness in cats using ultrasonography. A targeted literature search of PubMed and Google Scholar (2000–2024) using the terms “feline urethra,” “ultrasound,” and “urethral thickness” identified no relevant studies reporting ultrasonographic reference ranges in cats. Accordingly, the objectives of this study were fourfold: (1) to establish ultrasonographic reference ranges for total urethral thickness in clinically normal cats; (2) to evaluate variations based on breed, sex, and neutering status, as well as the influence of body weight and bladder volume; (3) to compare total urethral thickness between clinically normal cats and those presenting with lower urinary tract signs (LUTS); and (4) to determine a diagnostic cutoff value for detecting urethral abnormalities. 

2 Materials and methods 

2.1 Animals 

This retrospective multicenter study was conducted at Jeonbuk National University Animal Medical Center and VIP Animal Medical Center between April 2021 and May 2025. A total of 750 ultrasonographic images with corresponding medical records were initially reviewed, and 302 cats that met the inclusion criteria were ultimately enrolled. Clinically normal cats were defined as those with no history of lower urinary tract disease, no clinical signs such as dysuria or hematuria, and no abnormalities on urinalysis performed within one week of the ultrasound examination. Cats with LUTS were defined as those exhibiting clinical signs such as hematuria or pollakiuria. Exclusion criteria included: (1) poor visualization of the urethral wall on ultrasonography; (2) presence of a urethral catheter before or during examination; (3) overdistension of the urinary bladder resulting in urethral luminal filling, which precluded adequate urethral collapse; and (4) significant fecal accumulation in the descending colon causing external urethral compression.  This study was approved by the Institutional Animal Care and Use Committee of Jeonbuk National University, Iksan-si, Jeollabuk-do, Republic of Korea (Approval No. NON2024–172). 

2.2 Measurements 

Ultrasound images were obtained using the following systems: Aplio 300 (Canon Medical Systems, Europe B.V., Zoetermeer, Netherlands) with a 12-MHz linear array 18 L7 transducer; Aplio i800 (Canon Medical Systems, Tokyo, Japan) with a 12-MHz linear array i18LX5 transducer; or Aplio i700 (Canon Medical Systems, Tustin, CA, United States) with a 12-MHz linear array i18LX5 probe. All cats were positioned in dorsal recumbency, and the urethra was imaged in the mid-sagittal plane.  The method for measuring urethral thickness was adapted from a previously published canine study (15). Measurements were obtained at the urethral segment immediately cranial to the pelvic symphysis, just before acoustic shadowing from the pelvis obscured visualization (Figures 1A,B). This site was chosen to minimize the effect of luminal distension, as the distal urethra in this region remains consistently collapsed and visible on ultrasound (15, 16). The same anatomical landmark was applied to both male and female cats. Total urethral thickness was defined as the linear distance from the ventral hyperechoic leading edge to the dorsal hyperechoic trailing edge of the collapsed urethral wall (15) (Figures 1C,D).  Figure 1. Measurement of total urethral thickness. Schematic illustrations (A,B) and mid-sagittal ultrasonographic images (C,D) show measurement of urethral thickness in a male (A,C) and a female cat (B,D). Measurements were obtained immediately cranial to the pelvic bone, just before acoustic shadowing from the pelvis obscured visualization. The distance was measured from the ventral hyperechoic leading edge to the dorsal hyperechoic trailing edge. BG, bulbourethral gland; UB, urinary bladder.  Bladder volume was measured in a subset of 70 clinically normal cats for which both sagittal and transverse images of the urinary bladder were available. With each cat positioned in dorsal recumbency, bladder dimensions were measured as follows: maximal length and height in the sagittal plane, and maximal width in the transverse plane. Bladder volume was calculated using the prolate ellipsoid formula (volume = length × width × height × 0.523), which has been validated in feline patients (17). All measurements were performed using RadiAnt DICOM Viewer (version 2023.1, 64-bit, Poznań, Poland).  For intraobserver reliability, a single investigator (S.L.) performed each measurement twice. For interobserver reliability, three residents in the Veterinary Medical Imaging Department at the Teaching Hospital of Jeonbuk National University (S.L., Y.C., and J.L.) independently measured urethral thickness using the same image sets. Both intra- and interobserver assessments were performed by reviewing ultrasonographic video clips (cine loops), from which each observer independently selected the optimal frame for measurement. 

2.3 Statistics 

All statistical analyses were performed using IBM SPSS Statistics (version 27.0; IBM Corp., Armonk, NY, United States). Data are presented as mean ± standard deviation. Before applying parametric tests, the assumptions of normality and homogeneity of variances were evaluated using the Shapiro–Wilk test and Levene’s test, respectively. One-way analysis of variance was applied to assess differences in urethral thickness among breeds. Independent-samples t-tests were used to compare urethral thickness between sexes, between neutered and intact cats, and between clinically normal and LUTS cats. Linear regression analysis was applied to evaluate associations between total urethral thickness and body weight (BW) or bladder volume. In addition, multiple linear regression analysis was performed to simultaneously assess the effects of LUTS status, BW, age, sex, and neutering status on total urethral thickness in the entire cohort.  Receiver operating characteristic (ROC) curve analysis was conducted to determine the optimal urethral thickness cutoff for distinguishing cats with LUTS from clinically normal controls. The cutoff was identified using Youden’s index, and the corresponding area under the curve (AUC), sensitivity, and specificity were reported. To evaluate model stability and correct for potential optimism bias, internal validation with 1,000 bootstrap resamples was performed. Intra- and interobserver reliability were assessed using two-way random-effects intraclass correlation coefficients (ICC) for absolute agreement, with 95% confidence intervals (CI). A p-value <0.05 was considered statistically significant, and a p-value <0.001 was considered highly significant. 

3 Results 

A total of 302 cats were included, comprising 141 females (124 neutered, 17 intact) and 161 males (148 neutered, 13 intact). The mean age was 7.59 ± 4.74 years (median, 7.42; IQR, 3.58–11.04; range, 0.25–24). The mean BW was 4.83 kg (range, 0.58–11.7).  The study population included the following breeds: Korean Shorthair (KSH, n = 164), Persian (n = 27), Russian Blue (n = 19), Scottish Fold (n = 18), Turkish Angora (n = 12), Siamese (n = 11), American Shorthair (n = 10), British Shorthair (n = 10), Ragdoll (n = 8), Abyssinian (n = 6), Maine Coon (n = 3), Bengal (n = 2), Domestic Shorthair (n = 2), Munchkin (n = 2), Norwegian Forest (n = 2), British Longhair (n = 1), Devon Rex (n = 1), Himalayan (n = 1), Khao Manee (n = 1), Minuet (n = 1), and Sphynx (n = 1).  Of the 302 cats, 240 were classified as clinically normal, and 62 presented with LUTS. The mean total urethral thickness in clinically normal cats was 2.20 ± 0.26 mm (95% CI: 2.17–2.23), compared with 2.75 ± 0.51 mm (95% CI: 2.62–2.88) in cats with LUTS. 

3.1 Comparison of total urethral thickness between breeds 

Among the 240 clinically normal cats, four breeds with a sample size greater than 10 were included in the analysis: KSH (n = 131), Persian (n = 26), Russian Blue (n = 16), and Scottish Fold (n = 14). Mean total urethral thickness was 2.24 ± 0.26 mm (95% CI: 2.20–2.29) in KSH, 2.19 ± 0.22 mm (95% CI: 2.10–2.27) in Persian, 2.18 ± 0.30 mm (95% CI: 2.02–2.34) in Russian Blue, and 2.12 ± 0.20 mm (95% CI: 2.01–2.23) in Scottish Fold. No statistically significant difference in urethral thickness was observed among these breeds (F = 1.757, p = 0.157). 

3.2 Comparison of total urethral thickness between sexes 

Among the 240 clinically normal cats, 123 were male and 117 were female. Mean total urethral thickness was 2.19 ± 0.26 mm (95% CI: 2.14–2.23) in males and 2.22 ± 0.24 mm (95% CI: 2.18–2.26) in females. Although the mean was slightly higher in females (mean difference, 0.03 mm), the difference was not statistically significant (p = 0.299) (Table 1).  Table 1. Total urethral thickness (mean ± SD) according to sex and neutering status in clinically normal cats. 

3.3 Comparison of total urethral thickness between neutered and intact cats 

Of the 240 clinically normal cats, 214 were neutered (111 males, 103 females) and 26 were intact (12 males, 14 females). Mean total urethral thickness was 2.20 ± 0.25 mm (95% CI: 2.16–2.23) in neutered cats and 2.23 ± 0.25 mm (95% CI: 2.13–2.33) in intact cats, with no statistically significant difference (p = 0.593). When stratified by sex, no significant differences were found. Among females, mean thickness was 2.21 ± 0.24 mm in spayed cats and 2.27 ± 0.24 mm in intact cats (p = 0.390). Among males, mean thickness was 2.19 ± 0.26 mm in castrated cats and 2.18 ± 0.26 mm in intact cats (p = 0.887) (Table 1). 

3.4 Correlations between total urethral thickness and BW 

In clinically normal cats (n = 240), linear regression analysis showed no significant association between total urethral thickness and BW (R2 = 0.005; β = 0.011; p = 0.299). 

3.5 Correlations between total urethral thickness and urinary bladder volume 

In 70 clinically normal cats with both sagittal and transverse bladder images, no significant association was found between total urethral thickness and bladder volume (R2 = 0.002; β = 0.043; p = 0.727). 

3.6 Comparison of total urethral thickness between clinically normal cats and cats with LUTS 

Total urethral thickness was compared between clinically normal cats (n = 240) and cats with LUTS (n = 62). Mean urethral thickness was 2.20 ± 0.26 mm (95% CI: 2.17–2.23) in the normal group and 2.75 ± 0.51 mm (95% CI: 2.62–2.88) in the LUTS group. This difference was highly significant (p < 0.001) and corresponded to a very large effect size (Cohen’s d = 1.68; 95% CI: 1.37–1.99) (Figure 2; Table 2).  Figure 2. Comparison of total urethral thickness between clinically normal cats (n = 240) and cats with LUTS (n = 62). Urethral thickness was significantly greater in cats with LUTS (p < 0.001***). LUTS, lower urinary tract signs.  Table 2. Comparison of total urethral thickness between clinically normal cats and cats with lower urinary tract signs (LUTS).  ROC curve analysis yielded an AUC of 0.859 (95% CI: 0.794–0.925) (Figure 3). To minimize optimism bias and evaluate model stability, internal validation with 1,000 bootstrap resamples was conducted. The optimism bias was negligible (0.001), resulting in a bias-corrected AUC of 0.858 (95% CI: 0.784–0.918).  Figure 3. ROC curve analysis and optimal cutoff value distinguishing clinically normal cats from cats with LUTS. The curve derived from the original dataset yielded an AUC of 0.859. Bootstrap internal validation produced a bias-corrected AUC of 0.858 (95% CI: 0.784–0.918). The optimal cutoff was 2.49 mm, corresponding to a validated sensitivity of 75.9% (95% CI: 65.1–85.9) and specificity of 88.2% (95% CI: 84.0–91.9). ROC, receiver operating characteristic; LUTS, lower urinary tract signs; AUC, area under the curve; CI, confidence interval.  Two cutoffs were identified. A threshold of 2.62 mm corresponded to a bootstrap-validated sensitivity of 67.8% (95% CI: 55.9–79.3) and a specificity of 96.2% (95% CI: 93.6–98.4). A lower threshold of 2.49 mm yielded higher sensitivity (75.9%; 95% CI: 65.1–85.9) but lower specificity (88.2%; 95% CI: 84.0–91.9). Both cutoffs produced an identical Youden’s index of 0.641; however, 2.49 mm was selected as the optimal screening threshold owing to its superior sensitivity. Bootstrap validation confirmed the robustness of this cutoff, with 2.49 mm lying within the 95% CI for the optimal threshold (2.400–2.630 mm). 

3.7 Multivariable analysis of total urethral thickness 

To account for potential confounders, a multiple linear regression model was constructed (Table 3). The model, including BW, age, sex, neutering status, and LUTS status, explained 34.9% of the variance in urethral thickness (adjusted R2 = 0.338; F = 31.748; p < 0.001; n = 302). LUTS status showed a strong independent association with greater urethral thickness (B = 0.557 mm; 95% CI: 0.467–0.647; p < 0.001). BW demonstrated a borderline positive association of very small magnitude (B = 0.026 mm/kg; 95% CI: 0.001–0.051; p = 0.045), whereas age (B = −0.004 mm/year; p = 0.379), neutering status (B = −0.037 mm; p = 0.577), and sex (B = −0.010 mm; p = 0.804) were not significant. Collinearity diagnostics indicated no concerns (all VIFs ≤ 1.26; maximum condition index = 11.36).  Table 3. Multivariable linear regression analysis of factors associated with total urethral thickness in all cats (n = 302). 

3.8 Intraobserver and interobserver reliability 

To evaluate measurement consistency, intra- and interobserver reliability were assessed across all 302 cats. Intraobserver reliability, based on two repeated measurements by a single observer, showed an ICC of 0.988 (95% CI: 0.985–0.991; p < 0.001), indicating almost perfect agreement (Table 4). Interobserver reliability, based on measurements by multiple observers, also showed excellent consistency (ICC = 0.962; 95% CI: 0.953–0.969; p < 0.001) (Table 5).  Table 4. Intraobserver reliability for the total urethral thickness measurements of 302 cats using ICC and their 95% CI.  Table 5. Interobserver reliability for the total urethral thickness measurements of 302 cats using ICC and their 95% CI. 

4 Discussion 

To the best of our knowledge, this is the first study to establish ultrasonographic reference ranges for total urethral thickness in clinically normal cats and to evaluate their clinical utility in detecting abnormalities associated with LUTS. These findings support ultrasonography as a non-invasive, accessible diagnostic tool for evaluating FLUTD.  The mean total urethral thickness in clinically normal cats (2.20 ± 0.26 mm) was significantly lower than that previously reported in healthy small-breed dogs (3.15 ± 0.83 mm) (15). This interspecies difference likely reflects anatomical variations in urethral musculature. Specifically, feline urethral walls contain substantially less circular smooth muscle and fewer elastic fibers compared with those of dogs, and the total urethral musculature volume in cats has been estimated at approximately 72% of that in dogs (18). These anatomical factors likely account for the thinner urethra observed in cats.  In this study, urethral thickness was measured at the segment immediately cranial to the pelvic symphysis in both sexes. In males, this region corresponds to the pre-prostatic urethra, reflecting the caudal position of the prostate within the pelvic canal (19). By contrast, in previous canine studies, measurements were obtained from the urethral segment between the prostate and the pelvic symphysis, corresponding to the membranous (post-prostatic) urethra (15). Notably, the pre-prostatic urethra in male cats measures approximately 3–5 cm in length, whereas in dogs it is comparatively short (20–22). Therefore, even with similar transducer positioning, the anatomical segments assessed differ between species and should be considered when comparing urethral thickness measurements.  Previous canine studies have demonstrated significantly greater urethral thickness in males than in females (15); however, no significant sex-based difference was observed in cats in this study. This may reflect anatomical similarities in the measured region, as the pre-prostatic urethra in male cats has been reported to resemble the cranial half of the female urethra (3). These factors may limit direct interspecies comparisons of sex-related differences.  In this study, no statistically significant effect of neutering status on total urethral thickness was observed in either sex. Among females, only a small, non-significant difference was noted, with a mean of 2.27 mm in intact cats and 2.21 mm in spayed cats (mean difference, 0.06 mm). This comparison must be interpreted cautiously, however, given the substantial imbalance in sample sizes between neutered (n = 214) and intact (n = 26) cats, which reduced statistical power. Previous studies have reported that early-neutered cats may develop infantile external genitalia (23), and those spayed females have significantly smaller pre-pelvic urethral luminal diameters compared with intact females (24). Nevertheless, direct comparisons with the present findings are limited because those studies examined different anatomical parameters and did not account for age at neutering, which was unavailable in the current dataset. Further studies with larger, more balanced cohorts and documented age at neutering are needed to clarify potential neutering-related differences in urethral thickness within sex.  In clinically normal cats, no significant association was found between total urethral thickness and BW. This contrasts with findings in small-breed dogs, which demonstrated a very weak but statistically significant positive association (15). The discrepancy may reflect the narrower range of body size and weight in cats (25), suggesting that urethral thickness in clinically normal cats can largely be interpreted independently of BW. In the pooled cohort including LUTS cats, however, a very small association reached nominal statistical significance (B = 0.026 mm/kg; p = 0.045). Given the minimal effect size, this association likely reflects a statistical artifact arising from mixing two distinct populations (healthy versus LUTS) rather than a clinically meaningful influence of BW.  Previous studies have reported that measurement sites for total urethral thickness may vary depending on the degree of bladder distension (15). In this study, the effect of bladder filling on urethral wall thickness was evaluated in clinically normal cats. No significant association was identified between urethral thickness and bladder volume. These findings suggest that urethral thickness can be measured consistently regardless of bladder filling, supporting its reliability as a diagnostic parameter without requiring bladder volume standardization. Furthermore, because urethral thickness remains unchanged despite bladder or urethral distension (10), the established reference ranges may be broadly applicable across physiological states, irrespective of luminal diameter.  One strength of this study is the inclusion of a large and diverse clinical population spanning 21 feline breeds. However, interpretation of the reference range for normal urethral thickness should take into account the study population’s composition. The clinically normal group was heavily weighted toward Korean Shorthair cats (131/240). Although no significant breed differences were detected among the four most common groups (n > 10), the reference range of 2.20 ± 0.26 mm is likely most representative of this population. Future work with more evenly distributed breed cohorts is warranted to refine reference ranges and determine whether breed-specific differences exist across a wider spectrum of cats.  Cats with LUTS exhibited significantly greater urethral thickness than clinically normal cats (2.75 ± 0.51 mm vs. 2.20 ± 0.26 mm; p < 0.001). The very large effect size (Cohen’s d = 1.68; 95% CI: 1.37–1.99) underscores the diagnostic distinction between these groups and reinforces the clinical relevance of urethral thickness measurement. Prior histopathological studies in feline interstitial cystitis have described suburothelial proliferation, immune cell infiltration, von Brunn’s nests, neovascularization, elastin remodeling, and increased COX-2 expression in the proximal urethra (26). In the present study, three cats with LUTS demonstrated measurable reductions in urethral thickness following resolution of urinary signs. This suggests that urethral thickening may, in some cases, represent a dynamic and potentially reversible process such as inflammation or edema. However, this finding does not establish a uniform etiology. Because ultrasonography cannot resolve individual urethral wall layers due to limited spatial resolution (27), thickening should be interpreted as a nonspecific indicator of pathology, potentially reflecting inflammation, edema, fibrosis, or neoplasia. Although this limitation precludes identification of the exact underlying pathology, the findings suggest that ultrasonographic assessment can serve as a valuable non-invasive indicator of urethral abnormalities in cats with FLUTD.  This study has several limitations. First, urethral biopsy and histopathological analysis were not performed, limiting tissue-level confirmation of ultrasonographic findings. Accordingly, urethral wall thickening should be regarded as a nonspecific indicator, with the underlying etiology, such as inflammation, edema, fibrosis, or neoplasia, remaining undetermined. Second, although the clinically normal cohort was defined by strict criteria (absence of lower urinary tract disease, absence of clinical signs, and normal urinalysis), the presence of subclinical urethral or bladder disease cannot be fully excluded. Third, the intrapelvic urethra could not be evaluated due to acoustic shadowing from the pelvic bones, and focal lesions restricted to this region may have been overlooked. Fourth, the small number of intact cats (n = 26; females, n = 14; males, n = 12) reduced statistical power to assess the effect of neutering status, and modest but clinically relevant differences cannot be excluded. Moreover, the absence of data on age at neutering limited the evaluation of potential timing-related effects. Fifth, because this was a multicenter study, a mixed-effects model was not applied to account for variability between institutions or scanners. Sixth, intra- and interobserver ICCs were calculated from repeated measurements of the same ultrasonographic video clips rather than from independently reacquired examinations, potentially inflating agreement by not capturing variability introduced by patient positioning or probe handling. Finally, in rare cases of extensive bladder distension in male cats, measurements may have inadvertently included the post-prostatic urethra.  In conclusion, this is the first study to establish ultrasonographic reference ranges for total urethral thickness in clinically normal cats (2.20 ± 0.26 mm). Within this population, sex, breed, BW, and bladder volume were not significantly associated with urethral thickness. By contrast, urethral thickness was significantly greater in cats with LUTS. Multivariable analysis confirmed LUTS status as the strongest predictor of increased thickness. ROC analysis identified 2.49 mm as the optimal screening threshold, based on its superior sensitivity, and bootstrap internal validation confirmed the robustness of this cutoff. Exceeding this threshold may indicate underlying urethral pathology. Collectively, these findings support ultrasonographic urethral thickness measurement as a non-invasive tool for early detection and differentiation of FLUTD.  https://www.frontiersin.org/journals/veterinary-science/articles/10.3389/fvets.2025.1655498/full  ________________________________________________________________________________________________________________________________ TVP – Today’s Veterinary Practice Logo Articles | October 6, 2025 |  Issue: November/December 2025   Anesthetic Strategies for the Dental Patient   General practice encompasses both anesthesia and dentistry skill sets on a continuum from basic to advanced care, and it is up to the discretion of the practitioner to determine when a case should be referred.   Brook A. Niemiec, DVM, DAVDC, DEVDC, FAVD    Stephanie Hon, DVM, DACVAA    Abstract   Dental care for small animal veterinary patients requires high-quality anesthesia and pain management. Dental patients often have significant comorbidities along with their need for dental care, continuing into the geriatric period. With appropriate preanesthetic preparation and perianesthetic management, these patients can still receive quality dental care to support them throughout their life. Robust pain management and techniques that decrease inhalant anesthetic minimum alveolar concentrations can help manage common comorbidities such as mitral valve disease and chronic kidney disease. However, complex patient status or advanced dental disease may present a challenge to the provider. For such patients, anesthesia-free dentistry is not recommended; instead, referral to a specialist team will reduce surgery and anesthesia time and enable use of advanced monitoring techniques.   Take-Home Points    Pain control intervenes in the pain pathway at multiple points, and a multimodal, preemptive approach supports a continuum of analgesia throughout the patient experience.   Locoregional anesthesia offers numerous benefits for pain management and techniques for reducing intraoperative inhalant anesthetic minimum alveolar concentrations.   Periodontal disease can increase the risk for development of new renal or cardiac comorbidities and can exacerbate preexisting disease; although dental work should be encouraged for patients with these conditions, patients must be properly prepared and their conditions managed.   Anesthesia-free dentistry is not a viable treatment option.   A specialist dentistry and anesthesia team can help improve patient outcomes, especially for patients with complex status or advanced dental disease.   Pain interventions should be aligned with the degree of pain stimulus experienced by the animal.1 Ideal pain management would consist of a preventive, multimodal approach, intervening in the pain pathway at multiple points and attempting to avoid any perception of pain by the patient.1-3 To achieve this goal, a combination of oral, intravenous, locoregional, and nonpharmaceutical agents can be used to create a full complement of strategies to mitigate pain.   What are the commonly used analgesics in dental patients?   Analgesia has been proven to be more effective when administered preemptively (before the procedure) than postoperatively.4-6 Oral preemptive analgesia and sedation are often achieved with premedication designed to be administered by the client before bringing the patient to the hospital.7 Agents generally consist of gabapentin and trazodone, which have wide safety ranges. Pregabalin has also been investigated for preemptive use.8 Although generally aimed at reducing anxiety and allowing for ease of obtaining intravenous access, gabapentinoids can also be administered before the procedure. Although NSAIDs are also powerful analgesics, they are reserved for postprocedure administration due to their potential to lead to renal insult if hypotension has been difficult to mitigate under general anesthesia. Acetaminophen (dogs only) is also being increasingly added to the armamentarium of perioperative oral pain control options.1,9,10    NSAIDs provide excellent pain control for oral surgery, typically for 24 hours, and can be given intraoperatively or postoperatively (especially advantageous in the initial postoperative period when a patient may resent oral manipulation). NSAIDs should be used with aligned standards in feline patients (robenacoxib or low-dose meloxicam only) and in all patients with metabolic disease, especially renal impairment.11 Preoperative testing (including CBC, serum chemistry, and urinalysis) and close intraoperative blood pressure monitoring are critical for minimizing any anesthetic complications.    Opioids are the mainstay analgesic for acute pain, and their safety index is favorable.12 Full µ agonists (e.g., methadone, fentanyl, hydromorphone, morphine) are commonly used during surgery. For postoperative pain control, buprenorphine provides a step-down partial µ agonist effect, but it can be a useful option to send home with patients or administer in a sustained-release formulation. Butorphanol is generally not adequate for pain control because its effect size is limited.13    Additional constant-rate infusions (CRIs) have been investigated to complement opioids. Dexmedetomidine (an α2 agonist) has been shown to be as effective as morphine for postoperative pain control in dogs undergoing invasive surgery.3 Ketamine, an NMDA (N-methyl-D-aspartate) receptor antagonist, has been shown to effectively reduce scores indicating acute pain but also to prevent conversion to or treatment of chronic pain for oncologic palliative care.3   Which locoregional techniques are commonly used in dental practice?   Locoregional techniques are excellent for blocking transduction and transmission of the pain stimulus, beginning before any surgical stimulus is created until long into the postoperative period if long-term techniques are used.14 Locoregional anesthesia reduces overall systemic drug consumption, recovery times, and inhalation anesthetic minimum alveolar concentrations (MACs).15   Commonly used locoregional techniques include infraorbital, mental, and caudal mandibular blocks, which are best learned in a hands-on laboratory and are taught in most extraction courses. For a list from the lead author, including a virtual option, see vdspets.com.    Infraorbital block (FIGURES 1 AND 2): If properly performed, the infraorbital block affects the ipsilateral maxilla teeth, as well as associated soft tissues.16,17 The infraorbital canal runs rostrally just above the apices of the maxillary fourth premolar and exits the maxilla over the distal root of the third premolar. To approximate the dorsoventral location, imagine the fourth premolar being approximately the same size mesiodistally as corona-apically. Measure the width of the tooth and then that same distance dorsally from the cusp tip. The infraorbital canal is just apical to this point. Starting approximately over the second premolar parallel to the maxilla, advance the needle caudally, close to the maxillary bone. The depth is controversial; some veterinary dentists barely enter the needle into the canal, and others place the needle all the way caudally to the level of the second molar. These authors generally recommend insertion to the level of the medial canthus of the eye in mesocephalic and dolichocephalic dogs.16 Correct placement can be confirmed by gentle lateral movement of the needle, allowing it to engage the canal wall.   In brachycephalic dogs and in cats, the infraorbital canal is very short, which may easily allow for orbital penetration.16 The block will diffuse distally to the molars if a finger is placed over the foramen for 30 to 60 seconds after injection.17   Mental block (FIGURES 3 AND 4): The mental block affects the inferior alveolar nerve and anesthetizes the ipsilateral canine tooth to the central incisor, including the surrounding bone and associated soft tissue.16,17 For the block to be effective, the needle must be placed slightly within the canal.   In dogs, the middle mental foramen is located rostrocaudally apical to the mesial root of the second premolar; in cats, it is midway in the diastema between the canine tooth and the third premolar.16,18  Dorsoventrally, the middle mental foramen is approximately two-thirds of the distance down from the dorsal border of the mandible.   To perform a mental block, retract the mandibular labial frenulum ventrally and insert the needle at the rostral aspect of the frenulum and advance it at an approximately 45° angle along the mandibular bone until it just enters the canal. Confirm placement by moving the syringe laterally to encounter the lateral aspect of the canal.   Caudal mandibular block (FIGURES 5 AND 6): The inferior alveolar nerve enters the mandibular foramen on the lingual aspect of the caudal mandible.16,17 The caudal mandibular block is performed by infiltrating the nerve at this level before its entry into the canal.   To perform the intraoral approach, place the patient in dorsal recumbency with the mouth open. Approximate the width of the last molar tooth (M3 in dogs and M1 in cats), and insert the needle starting at 1 width of the tooth caudally from the caudal edge of the last molar. The needle is inserted into the mucosa on the lingual aspect of the mandible and advanced right along (ideally touching) the mandible. Insert the needle at a 45° angle caudally, advancing it along the bone approximately halfway ventrally from the dorsal aspect of the mandible. If this insertion is correctly performed, all mandibular teeth, bone, and soft tissue on the treated side are affected by this block.18    Utilize your dentistry veterinary nurses/techs for locoregional blocks and share this TVN article!     Is there a use for anesthesia-free dentistry, especially given the prevalence of patients with comorbidities such as advanced cardiac disease?   In the opinion of the authors (as well as numerous veterinary dentists and veterinary dental associations), the short answer is no; anesthesia-free dentistry (also called nonanesthetic dentistry) serves no medical purpose whatsoever. It is well established that it is not possible to fully diagnose oral and dental pathology without a thorough anesthetized oral examination (including periodontal probing and imaging) of an anesthetized patient.19-25 Furthermore, a professional dental cleaning includes supragingival and subgingival scaling as well as polishing of the teeth with power and/or hand instrumentation performed by a trained veterinary healthcare provider while the patient is under general anesthesia.23,26   One study showed that anesthesia-free dentistry may result in periodontal health that is worse than it was before the procedure.27 In addition, there are concerns about the emotional stress and potential physical injury that animals may endure during the procedure,26 which may be particularly applicable for patients with comorbidities for which sympathetic tone increase can have a significant negative effect. Last, when heart murmurs are properly diagnosed and optimized for anesthesia, morbidity has not been shown to be increased for those patients.28   What are the anesthetic strategies for dogs with cardiac disease?   In dental practice, one of the most common conditions among dogs is mitral valve disease. If not previously diagnosed, patients should be screened for heart disease by physical examination, history, murmur auscultation, NT-proBNP (N-terminal pro–B-type natriuretic peptide) testing, and/or electrocardiography.29 In specialty dental practice, cardiology consultation and echocardiography are recommended and often pursued by the client, which provides the anesthetist the most robust database to formulate a risk-management plan.   Protocol design can be guided by echocardiography findings (e.g., left atrium to aortic root ratio, systolic function, degree of regurgitation, presence of arrhythmias).29 Staging of heart disease will help determine if the dental procedure should be rescheduled to a later date to allow time for further stabilization. For instance, dental procedures for dogs with newly diagnosed stage B2 heart disease should be delayed to allow for commencement of medical therapy (e.g., pimobendan), and dogs with stage C heart disease should be confirmed free of any acute signs of heart failure before being admitted for dental procedures. The increased risk associated with anesthesia should be discussed with the client, including options for specialty dentistry and anesthesiology referral.   Before the patient is anesthetized, pimobendan and diuretics should be continued and a minimum database obtained (including volume and electrolyte status) to help guide intraoperative fluid therapy. To avoid refractory intraoperative hypotension, anesthesiologists often request that angiotensin-converting enzyme inhibitors and angiotensin receptor blockers be discontinued for at least 24 hours before arrival at the hospital.30 Patient handling should involve minimal stress as endogenous catecholamine surge can worsen cardiac regurgitation and precipitate disease exacerbation or an acute heart failure event. If intravenous access can be obtained, premedication with an opioid is ideal, followed by 3 to 5 minutes of diligent preoxygenation and, if possible, placement of preanesthesia monitoring (e.g., electrocardiography, noninvasive blood pressure measurement, blood oxygen saturation) to ensure vital signs are stable before induction. Induction can be achieved with carefully titrated alfaxalone or propofol, often with benzodiazepine coinduction. Partial intravenous anesthesia techniques (e.g., fentanyl CRI) can reduce the vasodilation and negative contractility effects of inhalant anesthetics.    Anesthetic management strategies focus on maintaining high-normal heart rates, avoiding afterload increases, and supporting contractility; patients with advanced disease may benefit from receiving care at a facility with advanced monitoring capabilities.31 Dobutamine (pure β agonist) is a preferred agent for treating hypotension.28 Fluid volume delivery (including any CRI) should not exceed 2.5 to 3 mL/kg/hour.   During anesthesia and continuing into the postoperative period, the anesthetist should monitor for signs of fluid overload and congestive heart failure. Desaturation and decreased chest compliance are signs that the patient may benefit from furosemide. During recovery, the patient should receive oxygen and flow-by oxygen should be available. Before discharge, respiratory rate and effort and clear respiratory auscultation should be documented.   Even if the patient’s dental disease is not severe, referral may be warranted for anesthesia management capability. When heart disease is properly screened for and managed, morbidity among affected dogs that were anesthetized by trained personnel and monitored diligently during routine dental procedures was no higher than that among dogs with lower American Society of Anesthesiologists status.32   What are the anesthetic strategies for cats with chronic renal disease?   Among geriatric cats, chronic kidney disease (CKD) is highly prevalent (up to 80%).33 In addition, periodontal disease has been implicated as a risk factor for CKD.33,34 Geriatric cats should be screened for CKD and, if present, their renal perfusion should be optimized and clients should be counseled as to potential exacerbation of CKD. The disease process is not expected to resolve, but the progression varies based on many risk factors and the control thereof.35 Therefore, the risk-to-rewards balance of pursuing dental treatment should be weighed, considering the staging of the CKD, management and stability of the condition, risks from the dental disease, and overall prognosis for survival from the primary disease process, all of which may involve multiple specialties (e.g., dentistry, internal medicine, anesthesia). For example, patients with CKD at International Renal Interest Society (IRIS) stage I and with moderate to severe dental disease may be candidates for pursuing dental treatment, whereas patients at IRIS stage IV with mild dental disease may not be.   Helpful diagnostics to screen for CKD in new patients include physical examination, CBC and chemistry, SDMA (symmetric dimethylarginine), and blood pressure.36 Common abnormalities include azotemia, anemia, electrolyte imbalances, acidemia, and hypertension. Previously undiagnosed CKD patients should be referred for CKD staging and management before general anesthesia is pursued for dental care. Comorbidities (especially concurrent heart disease) add to the difficulty as the management strategies for heart and kidney disease may directly oppose each other.    As with cardiac disease, low-stress handling avoids the increased renal vascular resistance and decreased renal perfusion that result from sympathetic stimulation.36 Oral pretreatment can be helpful; however, if intramuscular premedication is required for catheterization, as is often the case for cats, low-dose dexmedetomidine or alfaxalone can avoid major shifts in hemodynamics. Benzodiazepines or opioids are also appropriate, but these agents alone will not confer adequate sedation if temperament is difficult; often they are used adjunctively with the former 2 options. Alfaxalone and propofol are equivalently adequate choices for induction as long as care is taken to prevent hypotension. Ketamine is more extensively renally excreted in cats and therefore is not a good choice for patients with advanced CKD.36   To protect against further renal insult, techniques that reduce inhalant MACs (e.g., fentanyl CRI, locoregional blocks) and aggressive blood pressure management with adrenergic agonists help prevent hypotension. Target mean arterial pressure should be 70 to 80 mm Hg, unless the cat has been chronically hypertensive, in which case 20% of baseline should be achieved. Invasive pressure monitoring is a helpful advanced monitoring technique to tightly regulate blood pressure.36,37 In addition, electrolyte imbalances or metabolic acidosis are common among patients with CKD; therefore, these values should be monitored and ventilation should be controlled. An arterial catheter also facilitates serial bloodwork as needed.   Discretion should be used regarding whether to continue fluid therapy during the postoperative period until discharge; additionally, NSAID therapy, if elected, should be administered with extreme caution. New literature is redefining when NSAIDs may be appropriate for patients with underlying kidney disease, but the findings are new and broad applications are not yet clear. However, if the degree of inflammatory dental pain warrants it, it may be worth the risk for CKD exacerbation to cautiously administer NSAIDs.29    Summary   Anesthesia and dentistry are specialties that have long existed in concert with each other. General practice encompasses both anesthesia and dentistry skill sets on a continuum from basic to advanced care, and it is up to the discretion of the practitioner to determine when a case exceeds the expertise of their clinical practice and should be referred. With anesthesia consultation, remote guidance, or in-person referral, patients with intricate comorbidities can still be provided dental care and returned to oral health, either by their primary veterinarian or through referral to a specialty practice.   References  

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_______________________________________________________________________________________________________________________________  Journal of Veterinary Internal Medicine ACVIM I 02 October 2025  Evaluation of a Rapid, Low-Cost Broth Turbidity Test for Detecting Ampicillin-Resistant Lower Urinary Tract Infections in Dogs and Cats 

1. Cooper Brookshire | Larry Ballard | Anna Collinsgru | Josh Burnette | Khadija Ferdous | Joo You Park |Keun Seok Seo

First published: 02 October 2025  https://doi.org/10.1111/jvim.70259  Funding: This work was supported by the National Institutes of Health NIGMS (U54GM115428).  ABSTRACT  Background  Effective treatment of urinary tract infections (UTIs) in dogs and cats relies on timely recognition of antimicrobial resistance, but traditional microbiological culture and susceptibility testing require 48–72 h and can be cost-prohibitive.  Objective  To evaluate a novel, low-cost broth turbidity test for detecting ampicillin-resistant UTIs in dogs and cats compared to the gold standard microbiological methods.  Animals  One hundred sixty urine samples from 145 dogs and 15 cats at the Mississippi State University College of Veterinary Medicine.  Methods  From September 2023 to February 2024, urine samples were tested using an ampicillin-supplemented Mueller–Hinton broth turbidity test and gold standard culture with Sensititre MIC plates. Sensitivity, specificity, Cohen’s κ, and McNemar’s test were calculated.  Results  The broth turbidity test showed 89.47% sensitivity (95% CI: 66.86%–98.72%) and 100% specificity (95% CI: 97.42%–100%) for the detection of ampicillin-resistant organisms in the urine, with substantial agreement (κ = 0.94, p < 0.001) and no classification difference (p = 0.500). Notably, all 36 samples with ampicillin-susceptible organisms identified by the gold standard cultures test were correctly identified as negative for ampicillin resistance by the broth turbidity test.  Conclusions  The broth turbidity test’s simplicity and affordability make it a promising tool for in-house use by veterinary practitioners to guide first-line therapy decisions, though its sensitivity could be limited in cases with low bacterial loads or confounding factors such as recent antibiotic administration.  Abbreviations 

1 Introduction  Urinary tract infections (UTIs) are prevalent in dog and cat populations, often requiring prompt antimicrobial therapy to prevent complications such as pyelonephritis or recurrent infections. Amoxicillin and potentiated sulfonamides are both considered first-line treatments for uncomplicated UTIs, but amoxicillin is preferred by many practitioners due to its efficacy, safety, and cost-effectiveness [1]. Amoxicillin is excreted into the urine at a high concentration, which likely reduces the need for clavulanic acid for successful treatment of many infections [1]. However, the rising prevalence of ampicillin-resistant bacteria, particularly methicillin-resistant Staphylococcus pseudintermedius and extended-spectrum beta-lactamase-producing Enterobacterales, has complicated empirical therapy, leading to treatment failures and the use of second-line antibiotics [2]. Traditional microbiological culture and susceptibility testing, while the gold standard, are time-consuming (48–72 h) and usually require submission to off-site diagnostic laboratories [3]. Published veterinary guidelines state that “aerobic bacterial urine culture is preferred for all cases of suspected bacterial cystitis,” but surveys suggest that practitioners commonly prescribe antibiotics empirically for these cases, with cost being a major limiting factor [1, 4–7]. Low-cost diagnostic tools are essential for veterinarians working in resource-limited settings and for those providing care across the spectrum of care model. These tools support decision-making by enabling diagnostic testing that aligns with clients’ financial limitations while still promoting responsible antimicrobial use [8].  Rapid, cost-effective point-of-care diagnostic tools to detect ampicillin resistance in dog and cat UTIs are lacking, hindering timely and appropriate treatment decisions. Such tools are needed to guide first-line therapy, reduce unnecessary antibiotic escalation, and support antimicrobial stewardship.  The objective of this study was to develop a rapid, cost-effective, user-friendly microbial assay to reliably detect ampicillin-resistant bacteria in urine samples within 16–24 h as a point-of-care diagnostic. If the pathogen grows in the presence of the indicator drug (ampicillin), the broth will become visibly turbid, indicating positive growth of an amoxicillin-resistant microbe. A positive result will prompt the clinician to submit the sample for traditional culture and susceptibility testing at an accredited laboratory, thus avoiding inappropriate first-line therapy resulting in likely improved patient outcomes. This study aimed to evaluate the performance of the experimental broth turbidity test against traditional microbiological methods in detecting ampicillin-resistant lower UTIs in dogs and cats. We hypothesized that the test would exhibit high sensitivity and specificity for the detection of ampicillin-resistant bacteria in dog and cat urine, making it a practical tool for in-house use by veterinary practitioners.  2 Materials and Methods  2.1 Study Design and Sample Collection  This study was conducted in accordance with the Standards for Reporting of Diagnostic Accuracy Studies (STARD) guidelines to ensure transparent and comprehensive evaluation of the broth turbidity test’s diagnostic accuracy [9]. Urine samples submitted for routine culture and antibiotic susceptibility testing (AST) at the Mississippi State University College of Veterinary Medicine (MSU-CVM) Diagnostic Laboratory from September 2023 to February 2024 were tested in parallel using the experimental broth turbidity test. A total of 160 de-identified urine samples collected via cystocentesis from 145 dogs and 15 cats were used, obtained as residual samples from routine diagnostic submissions unrelated to this study. The MSU-CVM Institutional Animal Care and Use Committee (IACUC) reviewed the study and determined that no IACUC protocol was required, as no live animals were involved and only pre-existing diagnostic samples were analyzed. Owner consent for diagnostic testing was obtained as part of standard clinical procedures at the MSU-CVM Diagnostic Laboratory.  Due to the absence of published data on the broth turbidity test’s performance, a sample size of 160 urine samples was selected based on unpublished antibiogram data from Mississippi State University (2022–2023), estimating a 15% prevalence of ampicillin-resistant bacteria in dog and cat urine cultures. Assuming a 15% prevalence and at least a 90% sensitivity for the broth turbidity test (informed by our unpublished pilot experiments), approximately 24 resistant cases were expected, yielding a 95% confidence interval (CI) for sensitivity with a width of approximately ±10% using the Clopper–Pearson method [10]. This precision was deemed sufficient for evaluating diagnostic accuracy, consistent with STARD guidelines [9].  2.2 Gold Standard Traditional Microbiological Methods  Gold standard testing followed standard protocols for urinary bacterial culture and AST, as described by the Clinical Laboratory Standards Institute (CLSI). In summary, a calibrated 1 μL sterile loop was used to inoculate blood agar, Columbia nalidixic acid (CNA) agar, MacConkey agar, and an enrichment broth with urine. After 24 h of aerobic incubation at 37°C, colonies were manually selected from agar plates, isolated, and identified using Sensititre gram positive or negative ID plates (Thermo Fisher Scientific). If agar plates failed to grow after 24 h but the enrichment broth exhibited growth, subcultures were performed for bacterial isolation. Ampicillin susceptibility was determined using Sensititre CMV1BURF minimum inhibitory concentration (MIC) plates, with results interpreted per CLSI guidelines. An organism was classified as resistant (positive) if its MIC for ampicillin exceeded the CLSI susceptible breakpoint for lower UTIs in dogs and cats (8 μg/mL) [11].  2.3 Experimental Broth Turbidity Test  The broth turbidity test was designed for simplicity and affordability. A clear sterile polystyrene tube containing 2.5 mL of sterile cation-adjusted Mueller–Hinton (MH) broth and two 10 μg ampicillin discs (corresponding to the CLSI breakpoint of 8 μg/mL) were added. The tube was vortexed to ensure disc dissolution, then inoculated with 20 μL of urine (two 10 μL sterile loops). Twenty-microliters of urine was used as the inoculation volume based on our unpublished pilot studies that suggested it would be a reasonable volume. Broth tubes were incubated aerobically in a non-shaking incubator at 37°C overnight for 16–24 h. After incubation, tubes were gently hand-rocked to suspend any bacteria and visually assessed by two independent and blinded observers for turbidity compared to a negative control tube, with apparent turbidity indicating growth of ampicillin-resistant bacteria (positive), as demonstrated in Figure 1. Tubes with no visible turbidity were classified as no growth of ampicillin-resistant bacteria (negative). Observers were blinded to the results of the gold standard test at the time of turbidity assessment; gold standard results were not available until 24–48 h after turbidity was assessed.  FIGURE 1  Open in figure viewerPowerPoint  Broth turbidity test visual comparison. Tube A = negative control tube; Tube B = positive sample.  2.4 Statistical Analysis  The performance of the broth turbidity test was compared to the gold standard for detecting ampicillin-resistant bacteria. A 2 × 2 contingency table was constructed to calculate true positives, true negatives, false positives, and false negatives. Sensitivity and specificity were computed, with 95% CIs determined using the exact binomial (Clopper–Pearson) method via an online calculator [10]. Cohen’s κ was calculated to assess agreement beyond chance, and McNemar’s test was used to evaluate differences in classification between the two methods. Statistical analyses were performed using SPSS (version 28, IBM Corp.) or the Soper online calculator, with significance set at p < 0.05.  3 Results  3.1 Summary of Bacterial Species and Ampicillin MICs  Urine from 145 dogs and 15 cats submitted for routine AST was used for the study. Of the 160 urine samples analyzed, the gold standard method identified bacterial growth in 55 samples (34.4%), while 105 samples (65.6%) showed no growth. Among the 55 samples with bacterial growth, 36 (65.5%) contained only ampicillin-susceptible isolates (MIC ≤ 8 μg/mL), and 19 (34.5%) had at least one ampicillin-resistant isolate (MIC > 8 μg/mL). The experimental broth turbidity test, designed to detect ampicillin-resistant organisms, showed growth in 17 samples (10.6%) and no growth in 143 samples (89.4%). The broth test correctly classified all 36 ampicillin-susceptible samples as negative for ampicillin-resistant organisms (no growth) but misclassified 2 of the 19 gold standard identified ampicillin-resistant samples as no growth (negative for ampicillin resistance), indicating false negatives. Interobserver agreement for the broth turbidity test was 100%, with both observers classifying all samples the same (negative vs. positive). A 2 × 2 contingency table summarizing the detection of resistant organisms is presented in Table 1. The broth turbidity test demonstrated a sensitivity of 89.47% (95% CI: 66.86%–98.72%) and a specificity of 100% (95% CI: 97.42%–100%) for detecting ampicillin-resistant organisms. Cohen’s κ was 0.94 (p < 0.001), indicating almost perfect agreement between the broth turbidity test and the gold standard. McNemar’s test showed no significant difference in classification between the two methods (p = 0.500, exact test, two-sided).  TABLE 1. Contingency table for the broth turbidity test versus gold standard test. 

Susceptible isolates included a variety of species, predominantly Escherichia coli (n = 10) and Enterococcus faecalis (n = 7), with MICs ranging from < 0.12 to 4 μg/mL. Of the 36 ampicillin-susceptible cultures, 6 contained two isolates each. Resistant isolates were primarily E. coli (n = 11), with MICs ranging from 32 to > 256 μg/mL, alongside other species such as Klebsiella pneumoniae and Enterobacter cloacae. Of the 19 ampicillin-resistant cultures, 6 contained two isolates. Three of these cultures contained two morphologically distinct E. coli isolates, which were identified based on differences in colony morphology noted during isolation. Two discrepant result cultures were noted: one contained a mixed culture of S. pseudintermedius (MIC < 2 μg/mL) and Proteus spp. (MIC 16 μg/mL), and the other contained a β-lactamase-producing E. coli isolate (MIC > 256 μg/mL). Both discrepant result samples tested negative in the broth turbidity test despite demonstrating resistance by the gold standard. Table 2 summarizes the bacterial species and MIC ranges, categorized by susceptibility, resistance, and discrepant results.  TABLE 2. Summary of bacterial species and ampicillin MICs. 

a Discrepant Result 1 had two bacterial isolates: Ampicillin-susceptible S. pseudintermedius and ampicillin-resistant Proteus spp.  Notably, all 36 cultures identified by the gold standard as positive for ampicillin-susceptible organisms (e.g., Streptococcus spp., Staphylococcus pseudintermedius, E. coli) were correctly classified as negative for ampicillin resistance by the broth turbidity test. This further confirms the test’s 100% specificity for detection of ampicillin resistance (zero false positives), even in the presence of uropathogenic bacteria.  The two discrepant results (false negatives) involved samples with low bacterial loads. One sample (Discrepant Result 1) had 1000 CFUs/mL in the gold standard test and contained ampicillin-susceptible S. pseudintermedius and ampicillin-resistant Proteus spp., while the other (Discrepant Result 2) had < 1000 CFUs/mL, grew only in the gold standard’s enrichment broth, and contained ampicillin-resistant E. coli. These discrepant results were included in the analysis to ensure a conservative estimate of the test’s sensitivity. Further investigation revealed that Discrepant Result 1 was from an animal treated with cefovecin 2 days before sample collection, likely resulting in high urinary concentrations of cefovecin at the time of culture [12]. This almost certainly contributed to suppresion of bacterial growth in the broth turbidity test, rendering the result invalid [13]. Discrepant Result 2 involved a Proteus species with an ampicillin MIC of 16 μg/mL on the Sensititre MIC plate, which is within one dilution of the CLSI breakpoint (8 μg/mL). Due to the design of MIC plates (antibiotic concentrations double with each well), a reported MIC of 16 μg/mL actually indicates that the true MIC is > 8 but ≤ 16 μg/mL.  4 Discussion  This study evaluated a novel, low-cost broth turbidity test for detecting ampicillin-resistant lower UTIs in dogs and cats, with the goal of guiding first-line therapy decisions. The test exhibited high specificity (100%) and substantial agreement with the gold standard (κ = 0.94), making it a reliable tool for ruling out ampicillin resistance. Its sensitivity (89.47%) was slightly lower, primarily due to two false negatives in samples with low bacterial loads (≤ 1000 CFUs/mL). These discrepant results were retained in the analysis to provide a conservative estimate of sensitivity, ensuring that the test’s performance is not overestimated. The findings suggest that the test is a promising in-house option for veterinary practitioners, particularly in resource-limited settings where rapid results can inform whether amoxicillin is appropriate or if a formal culture is warranted.  The test’s 100% specificity is a key strength, as demonstrated by its ability to correctly classify all 36 cultures positive for ampicillin-susceptible organisms as negative for resistance. This ensures that practitioners can confidently use amoxicillin in such cases without risking inappropriate treatment escalation. The high positive predictive value in this sample population (100%) further supports its utility in identifying true resistant cases, prompting submission for formal culture and susceptibility testing. However, an important limitation of the broth turbidity test is that it is specifically designed to detect ampicillin-resistant organisms and does not distinguish between antibiotic-susceptible infections and cultures with no bacterial growth. As a result, a negative test result could indicate either the absence of infection or the presence of a susceptible infection, but the test cannot differentiate between these scenarios. Therefore, this test should only be used when the clinician has a high clinical suspicion of a lower UTI that warrants empiric treatment. If the turbidity test on a lower UTI urine sample suggests ampicillin susceptibility, clinicians can treat with confidence using guideline-recommended amoxicillin. If the turbidity test suggests amoxicillin resistance, amoxicillin could still be an effective treatment, but results will be less predictable. In this case, the client could be given the option to opt for a different empirical drug (e.g., potentiated sulfonamide) based on local antibiogram data or submit the urine sample for traditional bacterial culture and AST at a diagnostic lab.  The two false negatives highlight additional limitations. Discrepant Result 1 was likely confounded by recent cefovecin administration, which could have suppressed bacterial growth in the broth turbidity test due to high urinary concentrations of the antibiotic. Cefovecin, a third-generation cephalosporin, has a long half-life in dogs and cats, and it is well documented that antibiotics excreted into urine at the time of bacterial culture can inhibit the growth of organisms [12, 13]. In standard AST protocols, organisms are first isolated and grown in antibiotic-free media, then tested for susceptibility using purified colonies [14]. This approach allows bacteria to undergo exponential growth under ideal conditions before antibiotic exposure. In contrast, the broth turbidity test exposes bacteria to ampicillin without a prior isolation step. So, the bacteria were effectively transferred from cefovecin-containing urine directly to ampicillin-containing MH broth, potentially compounding the inhibitory effects of the antibiotics. These findings suggest that the broth turbidity test might be unreliable in patients recently treated with antibiotics and that clinical history, particularly recent antimicrobial use, should be carefully considered when interpreting results.  Discrepant Result 2 involved a Proteus species with an MIC of 16 μg/mL, just one dilution above the CLSI breakpoint of 8 μg/mL for ampicillin resistance and the concentration of ampicillin in the broth turbidity test. CLSI guidelines state that a margin of error of ±1 dilution is acceptable for MIC testing [14]. Additionally, reported MIC values are the highest value within the dilution range, meaning a reported MIC value of 16 has a true MIC value > 8 but ≤ 16 μg/mL [3]. Variability in the antibiotic content of Kirby–Bauer discs is also well documented, with studies reporting high variability in the true antibiotic content of discs [15]. If the true MIC of the Proteus isolate was closer to 8.1 μg/mL and the disc content was slightly above 10 μg (e.g., 11 μg), this could explain why the organism did not grow in the broth turbidity test, leading to a false negative. This highlights the importance of considering the inherent variability in both MIC testing and disc-based methods when interpreting diagnostic test results near the resistance breakpoint.  The CLSI susceptible breakpoint of 8 μg/mL for ampicillin susceptibility is likely conservative for lower UTIs in companion animals, as amoxicillin (ampicillin is used in vitro to predict amoxicillin susceptibility) achieves very high urinary concentrations—averaging > 200 μg/mL over a typical dosing interval for typical doses in both dogs and cats [16, 17]. In human medicine, amoxicillin has been shown to effectively treat lower UTIs caused by bacterial pathogens with MICs far exceeding this breakpoint, owing to these elevated urinary concentrations [18]. However, these high urinary concentrations are not applicable to upper UTIs, such as pyelonephritis, where tissue penetration is critical. Treatment of upper UTIs should be guided by AST using tissue-specific breakpoints to ensure adequate therapeutic concentrations at the site of infection.  The low prevalence of ampicillin-resistant isolates resulted in a small number of positive cases (n = 19), leading to a wide CI for sensitivity (66.86%–98.72%). Future studies with larger sample sizes or higher resistance prevalence could provide more precise estimates of the test’s performance. Additionally, the test’s reliance on visual turbidity assessment introduces subjectivity; future iterations could incorporate more objective turbidity assessments with a microbiology densitometer or simply by comparing to a set of standardized McFarland turbidity reference tubes to enhance reproducibility. Excluding patients with recent antibiotic exposure could further improve the test’s reliability, as demonstrated by the probable confounding effect of recent cefovecin administration in Discrepant Result 1.  The broth turbidity test’s simplicity—requiring only MH broth, ampicillin discs, sterile tubes, sterile inoculating loops, and a basic incubator—makes it accessible for in-house use, with very low material costs (e.g., under $5 per test). Compact low-cost incubators are widely available for purchase and could be used for other useful purposes in veterinary hospitals. For example, a broth without ampicillin could be inoculated to rule out uro-pathogens in cases such as cystitis in young, otherwise healthy cats. Traditional culture and susceptibility testing often exceed $100 per sample and can easily double the total cost of diagnosing and treating a UTI. In addition to the financial burden of the gold standard test, results typically require 48–72 h, delaying treatment decisions. By providing results within 16–24 h at a very low cost, the broth turbidity test enables practitioners to make timely decisions, potentially improving outcomes while encouraging the use of a first-line antimicrobial, a critical consideration in the context of antimicrobial stewardship [19].  5 Limitations  This study has several limitations. First, the low prevalence of resistant bacteria limited the number of positive cases, affecting the precision of sensitivity estimates. Second, the test’s performance in samples with low bacterial loads or recent antibiotic exposure suggests that modifications (e.g., larger inoculum volumes, exclusion of recently treated patients) might be needed to enhance sensitivity and reliability. Third, the study was conducted at a single diagnostic laboratory, and regional variations in resistance patterns might influence the test’s generalizability. While the broth turbidity test detects ampicillin resistance, it does not provide organism identification or susceptibility profiles for alternative antibiotics, necessitating follow-up testing for positive results. Finally, the study is limited by its in vitro design. Future studies should assess patient outcomes, along with in vitro susceptibility of bacterial isolates, to determine the usefulness of the diagnostic test more accurately.  6 Conclusion  The ampicillin broth turbidity test offers a rapid, low-cost method for detecting ampicillin-resistant lower UTIs in dogs and cats, with high specificity and substantial agreement with gold standard traditional microbiological methods. Its perfect specificity in identifying ampicillin-susceptible infections underscores its reliability in avoiding unnecessary treatment escalation. However, its sensitivity might be affected by low bacterial loads, recent antibiotic administration, or variability in MIC and disc content near the resistance breakpoint. The CLSI breakpoint of 8 μg/mL for ampicillin susceptibility is likely conservative for lower UTIs, given that amoxicillin achieves urinary concentrations greatly exceeding 8 μg/mL. The test’s clinical value could likely be maximized by limiting its use to infections with high CFUs, as identified by urinalysis, and excluding animals with recent antibiotic exposure.  Acknowledgments  The authors acknowledge Sarah Duncan for her technical assistance with sample processing. This work was supported by the National Institutes of Health NIGMS under Award Number U54GM115428.  Disclosure  Authors declare no off-label use of antimicrobials.  Ethics Statement  Authors declare no institutional animal care and use committee or other approval was needed. Authors declare human ethics approval was not needed.  Conflicts of Interest  The authors declare no conflicts of interest.  _________________________________________________________________________________________________________________________

AVMA I News 

AVMA guidelines for the use of telehealth in veterinary practice  IMPLEMENTING CONNECTED CARE  https://www.avma.org/sites/default/files/2021-01/AVMA-Veterinary-Telehealth-Guidelines.pdf  Generic feline hyperthyroidism tablets among new FDA-approved drugs  https://www.avma.org/news/generic-feline-hyperthyroidism-tablets-among-new-fda-approved-drugs?utm_source=delivra&utm_medium=email&utm_campaign=todays-headlines-news   _________________________________________________________________________________________________________________________ For indoor cats, wellbeing requires more than physical safety  By R. Scott Nolen  September 23, 2025                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                                              Ensuring feline health requires meeting both physical and emotional needs through thoughtful environmental design and caregiver awareness.  “Meeting the Physical and Emotional Needs of Indoor Cats” emphasizes that while an indoor lifestyle may protect cats from many physical dangers, safety alone does not guarantee good overall health and welfare.  Originally published in the Journal of Feline Medicine and Surgery, the position statement underscores that indoor cats face unique challenges. Without adequate enrichment, they may experience distress, defined as an inability to cope, that can lead to behavioral disorders and stress-related medical diseases.  In 2024, approximately 32% of U.S. households owned at least one domestic cat, totaling roughly 73.8 million pets, according to the 2024 AVMA Pet Ownership and Demographic Sourcebook.  “Indoor-only cats are often assumed to be the safest, but it is more challenging to meet their needs, impacting their physical and emotional health and resulting in more caregiver concerns about behavior,” Dr. Ilona Rodan, chair of the FelineVMA’s Feline Welfare Committee, said in a press release.  “This position statement helps caregivers and veterinary practices recognize the essential daily needs of cats who are often physically and emotionally underserved,” she added.  Central to the updated position are five pillars that support a healthy feline environment by providing the following: 

• A safe place  

• Multiple and separated key environmental resources  

• Opportunity for play and predatory behavior  

• Positive, consistent, and predictable human-cat social interaction  

• An environment that respects the cat’s sense of smell and other senses 

• The statement notes that many behavioral and medical conditions seen in feline patients are linked to the failure to meet these essential needs. By implementing the five pillars, veterinarians and caregivers can reduce distress and promote long-term wellbeing.