Presumptive herpesvirus-associated erythema multiforme in a cat.

Erythema multiforme (EM), an uncommon immune-mediated skin disorder of cats, conceivably could be triggered by feline herpesvirus type-1 (FHV-1) infection, in a manner analogous to human herpesvirus-associated EM (HAEM). This report describes a 10-year-old Persian-mixed cat with a presumptive diagnosis of HAEM.

L'érythème polymorphe (EM), est une dermatose à médiation immune rare chez le chat, théoriquement déclenché par une infection FHV-1 (feline herpesvirus type-1), de la même façon que chez l'homme avec HAEM (human herpesvirus-associated EM). Cet article décrit un chat croisé Persan de 10 ans avec un diagnostic présumé de HAEM.

El eritema multiforme (EM), un trastorno cutáneo poco común mediado por el sistema inmunitario de los gatos que posiblemente podría desencadenarse por una infección por herpesvirus felino tipo 1 (FHV-1), de manera análoga a la EM asociada al herpesvirus humano (HAEM). Este informe describe un gato persa mixto de 10 años con un diagnóstico presuntivo de HAEM.

Eritema multiforme (EM), uma doença de pele imunomediada incomum em gatos, em teoria pode ser desencadeada por infecção por herpesvírus felino tipo 1 (FHV-1), de maneira análoga ao EM associado ao herpesvírus humano (EMAH). Este relato de caso descreve um gato persa de 10 anos de idade com diagnóstico presuntivo de EMAH.

Ameloblastic fibro-odontosarcoma with mandibular bone invasion and regional lymph node metastasis in a cat: case report.

Odontogenic tumours are uncommon neoplasms in domestic animals, mostly solitary and locally infiltrative, but rarely metastatic. We report the case of a 13-year-old neutered male cat presented with a mandibular gingival neoformation. A computed tomography scan revealed an irregular neoformation with marked post-contrast enhancement, associated with lysis of the incisive bone and mandibular symphysis. Histologically, the oral mucosa and mandibular bone were infiltrated by a neoplasm consisting of a mixed population of odontogenic epithelium admixed with bundles of odontogenic ectomesenchyme, multifocally associated with hard tissue deposition. A spindloid cell component had metastasized to the right mandibular lymph node. The epithelial component was immunoreactive for cytokeratins (CK) 5/6, CK 14, pancytokeratin (CK AE1/AE3) and p63; the ectomesenchymal component was vimentin positive. A final diagnosis of ameloblastic fibro-odontosarcoma with bone invasion and lymph node metastasis was made. The findings indicate the metastatic potential of this rare tumour.

Conjunctival dacryops in two golden retrievers.

Two 5-month-old golden retriever dogs were referred for the evaluation of a mass arising from the left ventrolateral conjunctiva of the lower eyelid. The masses were externally located, deemed to be cystic in nature, and were surgically removed, and in one case, 0.15 mL of clear fluid was collected. Cytological examination of the aspirated fluid revealed proteinaceous, basophilic amorphous material, and few epithelial cells with foamy cytoplasm and small nuclei. No micro-organisms were detected. Histological examination of the cysts showed a wall composed of single to double cell layers. The cells were cuboidal to flattened, nonciliated, lined with mild submucosal connective tissues and slight inflammation composed of lymphocytes, plasma cells, and rare macrophages. In some areas, lobules of acinar glandular tissue were observed. To the authors' knowledge, this is the first case report of conjunctival dacryops in dogs. The complete surgical removal of the cysts was curative in both cases.

Multidetector-Row CT Findings in Dogs with Different Primary Parathyroid Gland Diseases.

Primary hyperparathyroidism in dogs is a possibly life-threatening condition, characterized by the excess of parathyroid hormone (PTH) secretion, which leads to an increase in serum ionized calcium level. The utility of computed tomography (CT) in the detection and characterization of parathyroid diseases in dogs has not been assessed to date. Therefore, the aim of this study was to describe the use of multidetector-row CT (MDCT) for the diagnosis of parathyroid disease in dogs. For this descriptive, single-center study, the database of the San Marco Veterinary Clinic was searched for dogs having a suspicion of parathyroid disease who underwent contrast-enhanced MDCT in the period from 2005 to 2021. Dogs with histopathology of the affected parathyroid gland were subsequently considered for inclusion. A total of 22 parathyroid glands were included: 12 adenomas, 8 adenocarcinomas, and two glands with hyperplasia. Several CT features were evaluated, including parathyroid gland affected, lateralization, shape, size, attenuation, and contrast-enhancement. Although the overlap between the appearance of different diseases exists, contrast-enhanced CT was a useful method for the diagnosis of parathyroid disease in dogs.

Conjunctival Extramedullary Plasmacytoma in Dogs and a Cat: Clinical Characteristics and Histopathological Findings.

BACKGROUND: Extramedullary plasmacytoma (EMP) is a plasma cell tumor that is very rarely reported in ocular and adnexal tissue and is usually solitary and benign. METHODS: This study evaluated seven cases from different ophthalmology referrals submitted for histopathological analysis between 2013 and 2022. RESULTS: EMPs were diagnosed in a 9-year-old domestic short-haired cat and in six dogs (median age, 10 years): three English Cocker Spaniels, a Golden Retriever, a Maltese, and a Pinscher. EMPs affected the third eyelid conjunctiva in five cases (5/7), followed by the superior bulbar (1/7) and palpebral conjunctivae (1/7), respectively, and were presented mostly as well-defined, salmon-colored nodules. Histopathologically, the masses were composed of sheets and packets of round cells morphologically consistent with mature plasma cells with mild anisocytosis and anisokaryosis; mitosis and binucleated giant cells were rarely observed. Follow up for 6/7 cases ranged from 6 months to 2 years. No signs of recurrence or systemic involvement (multiple myeloma) were observed. CONCLUSIONS: EMP should be included in the differential diagnoses of canine and feline conjunctival masses. Staging recommendations should include multiple myeloma diagnostic evaluation. Our results suggest that primary conjunctival EMP does not appear to be locally aggressive and has low systemic involvement behavior. The local surgical excision alone or combined with cryotherapy should be curative.

Acquired myasthenia gravis with concurrent polymyositis and myocarditis secondary to a thymoma in a dog.

Background: Canine thymomas are associated with multiple paraneoplastic syndromes, among which myasthenia gravis (MG) is the most common. Acquired MG is an autoimmune disease characterized by the presence of antibodies against acetylcholine receptors (ACHRs). ACHRs antibodies are the most commonly formed, but the production of antistriational antibodies binding to skeletal and cardiac muscle proteins has also been recorded both in humans and dogs. An association between the occurrence of antistriational antibodies and a severe form of myocarditis, giant cell myocarditis, has been described in humans. Case Description: A 4-year-old mixed-breed dog was referred because of 1 month history of exercise-induced weakness, hypersalivation, and regurgitation. The neurologic examination was indicative of a neuromuscular junction disease, and MG was suspected. A computed tomographic scan examination showed the presence of a megaoesophagus and a thymic mass. Serum antibodies against ACHRs confirmed the diagnosis of MG. Treatment with pyridostigmine was started, and the thymic mass was surgically excised, and a diagnosis of thymoma was confirmed by histology. 24 hours after surgery, the dog developed a third-degree atrioventricular block. Severe arrhythmia and increased troponin serum levels suggested myocarditis which rapidly led to cardiopulmonary arrest. Histopathologic examination of the heart, esophagus and diaphragm revealed a lymphocytic and macrophagic infiltration, consistent with myocarditis and polymyositis. Scattered rare giant multinucleated cells were also detected in the myocardium. Conclusion: To the author's knowledge, this is the first report of thymoma-associated MG with concurrent polymyositis and giant cell-like myocarditis in a dog.

Molecular and Immunohistochemical Expression of LTA4H and FXR1 in Canine Oral Melanoma.

Oral melanoma is a common canine tumor whose prognosis is considered ominous, but poorly predicted by histology alone. In the present study the gene and protein expression of Leukotriene A4 hydrolase (LTA4H) and Fragile-X-mental retardation-related protein1 (FXR1), both reported as related to metastatic potential in different tumors, were investigated in canine oral melanoma. The main aim of the study was to confirm and quantify the presence of LTA4H and FXR1 genes and protein in oral melanomas. A secondary aim was to investigate their association with histologic prognostic criteria (mitotic count, Ki-67 index). Formalin-fixed-paraffin-embedded canine oral melanomas (36) were collected and histopathological evaluation carried out. Immunolabelling for LTA4H and FXR1 and Ki-67 were performed. RT-PCR evaluated LTA4H and FXR1 gene expressions. Histologically, most tumors were epithelioid cell melanomas (19/36) and were amelanotic, mildly or moderately pigmented (5, 12 and 13/36 respectively), only 6 were highly pigmented. Mitotic count ranged 1-106, Ki-67 index ranged 4.5-52.3. Thirty-two (32/32) melanomas immunolabelled for LTA4H and 33/34 for FXR1. RT-PCR values ranged 0.76-5.11 ΔCt for LTA4H and 0.22-6.24 ΔCt for FXR1. Molecular and immunohistochemical expression of both LTA4H and FXR1 did not statically correlate with mitotic count or Ki-67 index. The present study demonstrates LTA4H and FXR1 gene and protein in canine oral melanoma, however their expression is apparently unrelated to histopathologic prognostic criteria. Although LTA4H and FXR1 seem unrelated to tumor behavior, their extensive expression in the present cohort of cases suggest that they may play a role in canine oral melanoma oncogenesis.

Immunohistochemical investigation of PNL2 reactivity of canine melanocytic neoplasms and comparison with Melan A.

PNL2 is a recently generated monoclonal antibody (mAb) that recognizes normal and neoplastic melanocytes. Although the antigen recognized by PNL2 remains unknown, recent studies of human and mouse melanomas have confirmed its usefulness as a diagnostic marker. In the current study, the immunoreactivity of PNL2 in canine melanomas was tested and compared with Melan A (A103). Validation of PNL2 was performed by Western blot analysis. PNL2 and Melan A immunoreactivity were tested on frozen samples of canine melanomas and on 69 formalin-fixed, paraffin-embedded melanocytic neoplasms. Normal canine tissues and nonmelanocytic neoplasms were included as negative controls. Western blot confirmed the presence of a protein recognized by the PNL2 antibody in canine melanomas. Immunohistochemically, PNL2 stained the melanocytic neoplastic cells with an intracytoplasmic, granular pattern. Among the melanocytic neoplasms tested, 62% stained positively with PNL2 and 59% with Melan A; 50.7% stained positively with both mAbs. The overall percentage of neoplasms that stained positively with at least 1 of these 2 antibodies was 68%. The extent of staining (i.e., the percentage of cells stained per specimen) was greater with PNL2 than with Melan A. With both mAbs, staining was most intense and diffuse in the epithelioid cell phenotype. Neither nonspecific staining nor staining in cells other than melanocytes was detected with either mAb. In contrast to human granulocytes, canine granulocytes were negative by both Western blot and immunohistochemical analyses. PNL2 mAb proved to be highly specific for the identification of formalin-fixed canine melanocytic neoplasms and should be a valuable diagnostic reagent.

Eyelid multiple cysts of the apocrine gland of Moll in Persian cats.

Feline eyelid hidrocystoma is a rarely reported disease of the apocrine glands of Moll that has been variably interpreted as proliferative/neoplastic lesion or retention cyst. The purpose of this paper was to investigate feline hidrocystoma pathogenesis by means of a histological and immunohistochemical study. Nine paraffin embedded biopsies of eyelid hidrocystoma were retrieved from our archives. Histological sections were immunostained with antibodies anti-cytoskeletal proteins and Ki67 antigen. All hidrocystomas were observed in Persian cats, seven males/two females, mean age 9.6 years. Histologically, single or multiple, variably sized cysts expanded eyelid dermis. Cyst was lined by cuboidal epithelium, occasionally raising in papillary structures. Immunostaining was consistent with apocrine gland epithelium (cytokeratin 8/18; 19 and 14 positive). Ki67 immunolabelled nuclei ranged from 5.3 to 20.83%. Although it was not possible to draw a definite conclusion concerning hidrocystoma aetiopathogenesis, the relatively high Ki67-proliferative index observed, suggested a proliferative nature of the lesion.

Repeated occurrence of jejuno-jejunal intussusception in a calf.

This paper reports the clinical findings, diagnostic imaging, surgical management, and necropsy of an unusual case of jejuno-jejunal intussusception in a calf that was diagnosed with the use of ultrasonography, and treated surgically by resection and end-to-end anastomosis. The calf fatally relapsed 8 d after laparotomy. Necropsy and histology revealed enteritis and myenteric ganglionitis.

Spinal epidural abscess in two calves.

OBJECTIVE: To report clinical signs, diagnostic and surgical or necropsy findings, and outcome in 2 calves with spinal epidural abscess (SEA). STUDY DESIGN: Clinical report. ANIMALS: Calves (n=2). METHODS: Calves had neurologic examination, analysis and antimicrobial culture of cerebrospinal fluid (CSF), vertebral column radiographs, myelography, and in 1 calf, magnetic resonance imaging (MRI). A definitive diagnosis of SEA was confirmed by necropsy in 1 calf and during surgery and histologic examination of vertebral canal tissue in 1 calf. RESULTS: Clinical signs were difficulty in rising, ataxia, fever, apparent spinal pain, hypoesthesia, and paresis/plegia which appeared 15 days before admission. Calf 1 had pelvic limb weakness and difficulty standing and calf 2 had severe ataxia involving both thoracic and pelvic limbs. Extradural spinal cord compression was identified by myelography. SEA suspected in calf 1 with discospondylitis was confirmed at necropsy whereas calf 2 had MRI identification of the lesion and was successfully decompressed by laminectomy and SEA excision. Both calves had peripheral neutrophilia and calf 2 had neutrophilic pleocytosis in CSF. Bacteria were not isolated from CSF, from the surgical site or during necropsy. Calf 2 improved neurologically and had a good long-term outcome. CONCLUSION: Good outcome in a calf with SEA was obtained after adequate surgical decompression and antibiotic administration. CLINICAL RELEVANCE: SEA should be included in the list of possible causes of fever, apparent spinal pain, and signs of myelopathy in calves.

Exophthalmos associated to orbital zygomatic mucocele and complex maxillary malformation in a puppy.

A case of exophthalmos due to zygomatic mucocele in a puppy with ipsilateral segmental maxillary atrophy is reported. A 7-month-old, mixed breed, male dog suffered the sudden-onset of unilateral painful exophthalmos and a gradual swelling of the right temporal region. A compressing, right retrobulbar mass was observed by ultrasound. Computed tomography revealed a large multiloculated cyst-like lesion of the right zygomatic gland projecting into the orbital space, thus displacing the eyeball. The ipsilateral molar part of the maxillary bone was underdeveloped, besides showing crowded, abnormal, multiple, unerupted maxillary molar teeth in the caudal maxillary region. Modified lateral orbitotomy and a selective caudal maxillary bone access were performed. The cyst-like lesion was removed and the zygomatic gland and the wall was collected for histology, which confirmed the mucocele. Clinical and imaging examinations six months after surgery showed neither recurrence of the mucocele nor ocular abnormalities. A possible common pathogenic mechanism involving these two conditions could be hypothesized.

Identification of bovine doppel protein in testis, ovary and ejaculated spermatozoa.

Doppel (Dpl) protein is a recently identified prion-like protein. Although Dpl might be expressed in the brain after prion gene deletion, in both human and mice Dpl is normally expressed only in testis and spermatozoa, where it appears to be involved in male fertility. Little information is available so far about the expression pattern of Dpl in bovines, thus, hampering possible research on the role of this protein in bovine infertility. We have thus, designed, produced and validated through Western blotting a polyclonal antibody against bovine Dpl. With this antibody we then screened bovine tissues for Dpl expression by immunohistochemistry. Ejaculated spermatozoa were screened by flow cytometry and immunocytochemistry. Bovine Dpl was expressed in all the developing stages of germinal cells, from spermatogones to ejaculated spermatozoa, in Sertoli cells and in ovarian follicles (granulosa cells and follicular fluid). Dpl immunoreactivity was also found on other tissues, where endothelial cells, peripheral nerves and scattered lymphocytes stained positive. This distribution pattern suggests that Dpl might be involved in sperm maturation/capacitation in bovines, like it might be in mice. This hypothesis needs to be verified by widespread application of the flow cytometric protocol established in this paper on spermatozoa from animals with reduced fertility.

Common bile duct obstruction due to a duodenal gastrinoma in a dog.

In dogs gastrinomas are rare endocrine neoplasms that have always been reported to arise from the pancreas. We report here what we believe to be the first case of a duodenal gastrinoma in a dog. A nine-year-old, male, Pekinese dog was presented with a three-day history of anorexia, vomiting and mucous diarrhoea. Clinical examination and laboratory findings suggested the presence of a severe hepatobiliary disorder. Abdominal ultrasonography showed a diffuse increase in echogenicity of the liver, with severe gallbladder dilation and marked dilation of the cystic duct, common bile duct and extrahepatic bile ducts. Based on these findings, an extrahepatic biliary tract obstruction (EBTO) of unknown cause was suspected. At laparotomy, the gallbladder and the extrahepatic bile ducts appeared severely dilated. The gallbladder was tense and could not be compressed suggesting an outflow obstruction. The duodenum at the level of the common duct orifice appeared slightly thickened and severely hardened for a length of 1 cm. Biopsies from the duodenum and liver were obtained and a cholecystoduodenostomy was performed. The duodenal biopsy revealed severe fibrosis of the submucosa and a infiltrate of small pockets and cords of round to polygonal cells with granular cytoplasm. Based on this appearance the differential diagnoses included neuroendocrine tumours and poorly differentiated carcinoma. Despite surgery and supportive therapy the dog continued to be anorexic and to vomit 3-6 times daily. After euthanasia and necropsy, histopathology showed the presence of a neuroendocrine neoplasia involving the duodenal wall with focal invasion of the adjacent pancreas and small liver metastases. On immunohistochemistry, the cytoplasm of approximately 90% of neoplastic cells intensely expressed neuron specific enolase and gastrin. These findings were consistent with a diagnosis of gastrinoma.

Bovine Doppel (Dpl) and prion protein (PrP) expression on lymphoid tissue and circulating leukocytes.

Doppel (Dpl) protein shares some structural features with prion protein (PrP), whose pathologic isoform (PrPsc) is considered to be the causative agent of transmissible spongiform encephalopathies. Dpl is mainly expressed in testes but, when ectopically expressed in the central nervous system, is neurotoxic. We have examined the expression pattern of Dpl and PrP on bovine lymphoid tissues and circulating leukocytes. A polyclonal anti-Dpl antibody along with a panel of monoclonal antibodies specific for leukocyte membrane antigens or PrP were used to examine frozen sections from spleen, lymph nodes, and bone marrow by immunohistochemistry. Blood was analyzed by flow cytometry. Double staining was used to study the possible coexpression of the two proteins and to characterize cells expressing Dpl and/or PrP. Dpl was expressed in B-cells, in dendritic cells within lymphoid follicles, bone marrow, circulating myeloid cells, and circulating B-cells. The distribution of Dpl was quite similar to that of PrP. The only differences in expression observed concerned the low number of Dpl+ cells in lymph nodes and the strong Dpl positivity of circulating granulocytes. The two proteins were rarely co-expressed, suggesting an independent expression mechanism in resting cells. The role of Dpl+ leukocytes in the pathogenesis of Dpl- or PrP-induced diseases merits further investigation.

Imaging diagnosis--split cord malformation.

The features of a calf with a split cord malformation are described. Clinically, there was severe cervicothoracic kyphoscoliosis and an interscapular dermal sinus associated with cerebrospinal fluid drainage. Using magnetic resonance imaging, complete duplication of the spinal cord at the cervical intumescence was detected. There was associated syringohydromyelia, multiple cervicothoracic vertebral malformations resulting in kyphoscoliosis and rachischisis, herniation of the cerebellar vermis, meningoencephalocele, and calvarial defects.