In situ squamous cell carcinoma of the gingiva and nictitating membrane associated with Felis catus papillomavirus type 3 in a cat.

Oral squamous cell carcinomas (OSCCs) are common cancers of cats. While papillomaviruses (PVs) are an important cause of human OSCCs, there is currently little evidence that PVs cause squamous cell carcinomas (SCCs) of the mouth or other mucosal surfaces in cats. In the present cat, in situ carcinomas developed on the gingiva and nictitating membrane. Neoplastic cells within both cancers contained prominent PV-induced cellular changes consistent with those caused by Felis catus PV3 (FcaPV3), and FcaPV3 DNA was amplified from both cancers. Neoplasms also contained intense nuclear and cytoplasmic p16CDKN2A protein (p16) immunolabeling, suggesting PV-induced degradation of retinoblastoma protein. The molecular and histological features strongly suggested the cancers were caused by FcaPV3 infection. This is the first report of an association between PV infection and the development of an in situ carcinoma of the mucosa of cats. The identification of these lesions suggests that PVs might cause a proportion of OSCCs, and SCCs from other mucosal surfaces, in cats.

Teat sinus and duct adenomatous hyperplasia in dogs.

Seventeen lesions diagnosed as teat sinus and duct adenomatous hyperplasia were identified in 10 dogs. All of the dogs were small breeds. Six were spayed female and 4 were male, 3 castrated and 1 intact. In 5 cases, the lesions involved multiple teats. They were pink to black, flattened to round, and sometimes crusted. Histologically, the lesions were usually pigmented (16/17), plaque-like to nodular masses composed of polygonal cells arranged in anastomosing trabeculae and bilayered ducts and/or cysts, with a fibrous to mucinous (Alcian blue-positive) stroma and squamous cysts (12/17). Scattered epithelial cells contained single, discrete, clear cytoplasmic vacuoles. Atypia was mild, and the mitotic count per 2.37 mm2 varied from 0 to 15 (average 2.7). Immunohistochemistry was performed on 14 of the lesions from 8 dogs. Epithelial cells were 100% panCK+ and included basally located CK14+/CK5_6+/p63+/calponin- cells and nonbasal CK19+/CK7+ cells. Cells manifesting squamous differentiation were usually panCK+/CK14+/CK5_6+/CK19-/CK7-/p63±/calponin-. In addition to fibroblasts, vimentin positivity was found in disseminated, round to stellate stromal and intraepithelial cells that often had black, granular, cytoplasmic pigment (consistent with dendritic/phagocytic cells and/or melanocytes). Of the 8 dogs for which clinical follow-up information was available, all were still alive and well, with no significant teat changes, development of mammary lesions or other masses 4 to 22 months (median 12.5) after biopsy. The histologic, immunohistochemical, and clinical findings were consistent with teat duct and sinus adenomatous hyperplasia. This is an uncommon, benign proliferative lesion that can involve multiple teats of female and male, small breed dogs.

Toxocara canis Larval Migration Causing Verminous Pneumonia in Fading Puppies From 2 Scottish Terrier Litters.

Migration of vertically transmitted Toxocara canis larvae through the liver and lungs is poorly documented as a cause of periparturient mortality in puppies. This case series describes 4 cases of fading puppies in 2 litters from 2 different bitches owned by the same breeder. Of the 4 cases, 4 had verminous pneumonia, 2 had fibrinoid necrosis of pulmonary arterioles, 4 had hepatic necrosis and inflammation, 2 had hepatic thrombophlebitis, and 1 had tracheal occlusion. These lesions were associated with migrating nematode larvae morphologically consistent with T. canis. The identity of the larvae was confirmed by sequencing of a portion of the ITS-2 region of nuclear ribosomal DNA. The tissues involved are consistent with the known migration pathways of this parasite. The dam of the first litter was negative for Toxocara spp. and other intestinal parasites by fecal floatation. This report highlights the need to consider T. canis migration in the differential diagnosis of fading puppies.

Endocrine fibroblast growth factors in domestic animals.

Fibroblast growth factors (FGFs) are a group of structurally homologous yet functionally pleiotropic proteins. Canonical and intracellular FGFs have primarily autocrine or paracrine effects. However, the FGF19 subfamily, composed of FGF15/19, FGF21, and FGF23, act as endocrine hormones that regulate bile acid, metabolic, and phosphorus homeostasis, respectively. Current research in human and rodent models demonstrates the potential of these endocrine FGFs to target various diseases, including disorders of inherited hypophosphatemia, chronic liver disease, obesity, and insulin resistance. Many diseases targeted for therapeutic use in humans have pathophysiological overlaps in domestic animals. Despite the potential clinical and economic impact, little is known about endocrine FGFs and their signaling pathways in major domestic animal species compared with humans and laboratory animals. This review aims to describe the physiology of these endocrine FGFs, discuss their current therapeutic use, and summarize the contemporary literature regarding endocrine FGFs in domestic animals, focusing on potential future directions.

Equus caballus papillomavirus Type 7 is a rare cause of equine penile squamous cell carcinomas.

Penile squamous cell carcinomas (SCCs) are common, potentially life-threatening neoplasms of horses. They are well-recognized to be caused by Equus caballus papillomavirus (EcPV) type 2, although EcPV2 cannot be detected in all cases. A 23-year-old standardbred gelding developed multiple penile in situ and invasive SCCs that contained histological evidence of PV infection. By using both consensus and specific PCR primers, these lesions were found to contain EcPV7 DNA, but not DNA from EcPV2 or any other PV type. To determine how frequently EcPV7 is present in equine penile SCCs, specific primers were used to detect EcPV2 and EcPV7 in a series of 20 archived samples. EcPV7 was the only PV detected in one, both EcPV2 and 7 were detected in five, and only EcPV2 was detected in 14 SCCs. EcPV7 DNA was also detected in three of 10 archived oropharyngeal SCCs, although only as a co- infection with EcPV2. This is the first report of EcPV7 causing disease in horses. These results suggest EcPV7 could cause a subset of equine penile SCCs, and this is the first evidence that PV types other than EcPV2 can cause these neoplasms. The detection of EcPV7 in the oropharyngeal SCCs suggests a potential role of this PV type in the development of these SCCs. There were no clinical or histological features that differentiated lesions containing EcPV7 DNA from those containing EcPV2 DNA. If EcPV7 causes a proportion of equine penile SCCs, vaccines to prevent EcPV2 infection may not prevent all equine penile SCCs.

Clinicopathologic observations on laryngoplasty failure in a horse.

OBJECTIVE: To report morphologic findings associated with laryngoplasty failure in a horse. STUDY DESIGN: Clinical report. ANIMALS: A 9-year-old Thoroughbred cross gelding. METHODS: Necropsy and histopathology were performed on a horse that died peracutely during anesthetic recovery after correction of a right dorsal displacement of the ascending colon. Three weeks earlier the horse had left laryngoplasty and ventriculocordectomy. RESULTS: Dissection of the larynx revealed that the laryngoplasty suture had pulled through the muscular process of the left arytenoid cartilage, which appeared grossly normal. Histopathology of the arytenoid muscular process revealed cartilage necrosis, granulation tissue, and inflammation around the cartilage and within the cartilage failure line, and small numbers of coccoid bacteria in a minority of cartilage canals. Multifocal cardiomyopathy and pulmonary congestion, edema, and hemorrhage were also observed histologically. CONCLUSION: Death was attributed to peracute pulmonary edema associated with cardiac abnormalities and airway obstruction from laryngoplasty failure. Morphologic changes in the muscular process indicate gradual progression toward laryngoplasty failure, possibly associated with suture-induced pressure necrosis and/or microscopic low-grade postoperative infection.

Cutaneous xanthoma causing hypercalcaemia in a cat.

CASE SUMMARY: A 5-year-old male neutered cat weighing 3.56 kg presented owing to the development of two masses over the dorsal cervical and cranial thoracic areas, as well as weight loss, inappetence and vomiting. Diagnostic tests revealed a grossly lipaemic sample with hypercholesterolaemia (440 mg/dl; reference interval [RI] 90.0-205.0), hypercalcaemia (>16.0 mg/dl [RI 8.0-11.8]) and urine specific gravity 1.022 (RI ⩾1.035). When re-presented 9 months later, fasted blood analyses revealed elevated ionised calcium (1.87 mmol/l [RI 1.11-1.38]), persistently elevated total calcium, normal phosphate and persistent minimally concentrated urine with calcium oxalate dihydrate crystals. Ultrasound-guided fine-needle aspiration of the masses produced blood-tinged purulent fluid with negative culture results. Excisional biopsies of both masses were undertaken, and histopathology was consistent with cutaneous xanthoma. No organisms were identified with special staining, and deep-tissue culture did not grow bacteria or fungi. Postoperatively, repeat fasted biochemical analysis revealed persistent hypercholesterolaemia with normal triglycerides, and normalisation of ionised and total calcium levels. Based on these findings, a diagnosis of cutaneous xanthoma causing hypercalcaemia due to primary dyslipidaemia was made. The cat was reported to be significantly improved in comfort and energy levels postoperatively and a transition to a fat-restricted diet was instituted. Eight months after xanthoma removal no recurrence was reported. RELEVANCE AND NOVEL INFORMATION: To our knowledge, this is the first report of cutaneous xanthoma and associated granulomatous inflammation causing hypercalcaemia due to dyslipidaemia in a cat. Familial hypercholesterolaemia is an example of a primary condition that could cause dyslipidaemia in cats, and further studies are warranted to better describe the genetic characteristics. Xanthoma formation and the resultant granulomatous inflammation should be considered in cases of hypercalcaemia.

Acute and severe haemorrhage following pentosan polysulfate injection in a Cornish Rex.

CASE SUMMARY: A 14-year-old male castrated Cornish Rex cat was referred for lethargy progressing rapidly to collapse in the hours following a subcutaneous injection of a product containing 100 mg/ml pentosan polysulfate sodium and 168 mg/ml glucosamine. Physical examination revealed the cat to be in hypotensive shock with swelling and interstitial oedema around the cranial thorax and caudal cervical regions without cutaneous haemorrhage. Initial diagnostics revealed a severe anaemia (packed cell volume 11%) which later deteriorated further, necessitating a blood transfusion and aggressive fluid therapy. Post-transfusion, the patient remained dyspnoeic and subsequent diagnostics found evidence of pre-existing cardiomyopathy and congestive heart failure. The cat was euthanased 24 h following presentation due to increasing dyspnoea. Post-mortem findings were of severe subcutaneous and intermuscular haemorrhage over the neck and thorax, among other changes. There were no detectable levels of coumarin anticoagulants in the liver. RELEVANCE AND NOVEL INFORMATION: This is the first reported case of acute subcutaneous and intermuscular haemorrhage of this severity suspected to be related to the off-label use of an injectable product containing pentosan polysulfate in a cat. Given the popularity of its use for feline arthritis, there is a need for large-scale clinical trials to evaluate the safety and efficacy of products containing pentosan polysulfate for cats, and any side effects to be reported.

Evidence from a Series of 104 Equine Sarcoids Suggests That Most Sarcoids in New Zealand Are Caused by Bovine Papillomavirus Type 2, although Both BPV1 and BPV2 DNA Are Detectable in around 10% of Sarcoids.

Equine sarcoids are common mesenchymal neoplasms of horses that are caused by cross-species infection by deltapapillomaviruses. While bovine papillomavirus (BPV) 1 and 2 are the most common causes, there are differences between countries regarding which of these BPV types cause the majority of sarcoids. Additionally, no causative PV can be detected in a subset of sarcoids, suggesting that other PV types could be rarer causes of these neoplasms. In the present study, consensus PCR primers and PCR primers specific for the five deltapapillomavirus types currently known to cause mesenchymal neoplasia (BPV1, BPV2, BPV13, BPV14, and Ovis aries PV2 DNA) were used to investigate the presence of PV DNA in 104 sarcoids from three defined regions in New Zealand and from two distinct time periods separated by 15 years. PV DNA was detected in 94 (90.4%) sarcoids. Of the sarcoids containing PV DNA, 83 (88.3%) contained only BPV2 DNA, 9 (9.6%) BPV1 and BPV2 DNA, and 2 (2.1%) only BPV1 DNA. No other PV types were detected. The predominance of BPV2 is consistent with studies of sarcoids from North America but dissimilar to studies of sarcoids from Europe and Australia. Detection rates of BPV1 and BPV2 were similar in sarcoids from different regions of New Zealand and in sarcoids from different time periods. These results suggest that most equine sarcoids in New Zealand are caused by BPV2 and thus if vaccines are developed to prevent sarcoids, vaccines that provide good protection against BPV2 will be required in this country.

Detection of a Putative Novel Papillomavirus Type within a Large Exophytic Papilloma on the Fetlock of a Horse.

A 10-year-old horse presented with two 3-cm diameter exophytic masses over the fetlock. Histology was consistent with a hyperplastic squamous papilloma and numerous cell changes consistent with papillomavirus (PV) infection were visible. Partial sequences of PV L1 and E1 ORFs were amplified using consensus PCR primers. The sequences were most similar to Equus caballus type 1 (EcPV1). However, as the sequences were only around 73% similar to EcPV1, they appear to be from a novel PV type that is likely to be within the Zetapapillomavirus genus. The papillomas were treated with topical imiquimod and resolved within 14 weeks. The clinical presentation of the papillomas in the present case had marked differences to the clinical presentation of EcPV-1-induced papillomas, which are typically small, numerous and around the face. Observations from the present case increase the clinical spectrum of PV-induced lesions in this species as well as providing evidence of an additional novel papillomavirus that is able to cause disease in horses.

Listerial mesenteric lymphadenitis in 3 cats.

BACKGROUND: Listeriosis is a rare disease in cats with naturally occurring cases usually being identified in individual animals. Listerial mesenteric lymphadenitis has not been described previously in cats. OBJECTIVES: To describe the clinical and histological features of listerial mesenteric lymphadenitis in cats as well as treatment outcome. ANIMALS: Listerial mesenteric lymphadenitis was confirmed in 3 cats by histology, immunohistochemistry, and bacterial culture. RESULTS: The affected cats were young to middle aged and were examined for various clinical signs. On both palpation and abdominal ultrasound examination, all cats had marked mesenteric lymphadenomegaly. Survival was prolonged in all 3 cases. Two of the 3 cats were fed a raw meat-based diet before they developed clinical illness. CONCLUSIONS AND CLINICAL IMPORTANCE: Lymphadenitis caused by listeriosis has a protracted time course and should be a differential diagnosis for abdominal lymphadenopathy in young to middle-aged cats. Feeding of a raw meat-based diet may be a contributing factor for development of listeriosis in cats.

Retrospective study of the relative frequency of feline hepatobiliary disease in New Zealand based on 10 years of hepatic biopsy samples.

AIMS: To retrospectively determine the relative frequency of feline hepatobiliary diseases from biopsy specimens submitted to a single laboratory across a 10-year period and to establish whether age, sex or breed associations exist. METHODS: Histopathological data from 154 liver biopsies of New Zealand cats sampled between 2008 and 2018 were analysed. The samples were allocated to primary, secondary and tertiary disease categories using criteria established by the World Small Animal Veterinary Association. Breed associations were derived using ORs and 95% CIs. Gender and age associations were also evaluated. RESULTS: The most frequently diagnosed hepatobiliary diseases were lymphocytic cholangitis (20 per cent), hepatitis (16.9 per cent), reversible hepatocellular injury (16.4 per cent), neutrophilic cholangitis (9.7 per cent), haematopoietic neoplasia (9.7 per cent), hepatocellular neoplasia (5.6 per cent) and cholangiocellular neoplasia (4.1 per cent). Burmese cats were found to be at significantly increased risk of both biliary and parenchymal diseases and Birman cats to be at significantly increased risk of parenchymal disease. Domestic longhair cats were at significantly increased risk of hepatobiliary neoplasia. Birman cats were at significantly increased risk of hepatitis while domestic shorthair cats were at significantly decreased risk of neutrophilic cholangitis, reversible hepatocellular injury and hepatitis. CONCLUSIONS: This study is the first retrospective examination of the relative frequency of hepatobiliary disease in biopsy specimens from New Zealand cats. Some breeds were associated with specific histopathology.

Successful treatment of vaginal malakoplakia in a young cat.

CASE SUMMARY: A 3-year-old, female, spayed, domestic shorthair cat presented for dysuria and haematuria, unresponsive to antibiotic treatment. A small, fleshy, erythematous mass protruded from the vaginal vault. Ultrasound identified a vaginal mass effect with mixed echogenicity measuring in excess of 3 cm. Vaginoscopy confirmed an extensive, fleshy, irregular mass that was characterised histologically as pyogranulomatous vaginitis, with periodic acid-Schiff-positive macrophages containing gram-negative bacteria. Fluorescence in situ hybridisation analysis demonstrated invasive intracellular Escherichia coli. Vaginal malakoplakia was diagnosed. Tissue culture and antimicrobial susceptibility of E coli was used to guide treatment. A 6 week course of enrofloxacin 5 mg/kg q24h resulted in complete resolution of the mass and clinical signs. RELEVANCE AND NOVEL INFORMATION: Malakoplakia is a rare chronic inflammatory condition that has been previously reported in the bladder of two cats. The pathogenesis of malakoplakia is thought to involve ineffective killing of bacteria (eg. E coli), similar to granulomatous colitis in Boxers and French Bulldogs. The literature on malakoplakia in cats is sparse. This is the first reported feline case with vaginal involvement, intracellular E coli and successful treatment with a fluoroquinolone. Malakoplakia is an important, non-neoplastic differential diagnosis when a mass is identified in the urogenital system of a young cat.