Mucopolysaccharidosis VI in a Siamese/short-haired European cat

A 3-year-old Siamese/short-haired European cat was referred for clinical disease characterized by dwarfism, facial dysmorphia, paralysis, small and curled ears, corneal clouding and large areas of alopecia. X-ray examination showed multiple bone dysplasia. On the basis of clinical features a form of mucopolysaccharidosis was suspected. The cat, killed at the owner's request, presented several severe skeletal deformities such as long caudal limbs, enlarged thorax with sunken breastbone, vertebral ankylosis in many spinal segments and visceral involvement. Histologically, the cat showed diffuse vacuolization and enlargement of cells in cartilage, bone and visceral organs. Ultrastructurally, membrane-bound vacuoles were filled with fibrillar and fluffy-material or concentrically whorled lamellae. Arylsulphatase B activity was 3.24 nm/mg/h in the affected cat and 30.6 in a normal age-matched control (NC). The L-iduronidase activity was slightly increased. Quantitation of total glycosaminoglycans (GAGs) revealed a 4.5-fold increase in the affected cat as compared with NC, while electrophoretic run of specific GAGs [chondroitin sulphate (CA); hyaluronan (HA); heparan sulphate (HS); dermatan sulphate (DS); keratan sulphate (KS)] performed on a cellulose acetate sheet, showed a striking increase in the DS band. On densitometric analysis of the electrophoretic run stained with Alcian Blue 8GX, the absorption of DS was eight-fold increased as compared with NC. The clinical and morphological features, and the biochemical findings, were consistent with the diagnosis of feline mucopolysaccharidosis VI.     

Pancreatic cyst in a cat

CASE HISTORY: A 5-year-old neutered male Cornish Rex cat was presented for evaluation with a history of vomiting over the previous 5 days.

CLINICAL FINDINGS: An abdominal mass was palpated, which was shown to be cystic by ultrasound examination. Exploratory surgery revealed this to be associated with the pancreas and it was duly resected. Histopathology was performed on the cystic mass.

DIAGNOSIS: Pancreatic cyst with associated chronic active infl ammation.

CLINICAL RELEVANCE: This is the first report of a true pancreatic cyst in a cat.     

Acquired arachnoid cyst in a cat

A 5-year-old Birman cat presented with paraparesis associated with a fracture of the third thoracic vertebra and was managed conservatively. Voluntary function was regained over the next 6 months, but the cat was referred 4 years after the trauma because of recurrence of hindlimb paresis and ataxia. Magnetic resonance imaging (MRI) showed a spinal arachnoid cyst at the level of the fourth thoracic vertebra, which was treated surgically by dorsal laminectomy and durectomy, and hindlimb function subsequently recovered. The cat re-presented 4 years later for recurrent hindlimb paresis. Myelography and computed tomography–myelography (CT-M) showed dorsolateral pooling of cerebrospinal fluid (CSF) at the previous laminectomy site. The neurological signs after the second surgery improved, but not as much as after the first surgery and the cat remained ataxic with moderate paresis. Seven months later repeat CT-M revealed an atrophic spinal cord, but negligible pooling of CSF at the previous site of the arachnoid cyst. The cat could walk, but was being treated for self-induced trauma of the left hindlimb that was thought to be related to paraesthesia. The neurological signs gradually deteriorated over 3 months and the cat was euthanased.     

Choanal atresia in a cat

CASE HISTORY: A 5-month-old domestic shorthair kitten with a history of chronic left unilateral nasal discharge was examined.

CLINICAL FINDINGS: Endoscopy and computed tomography (CT) demonstrated a complete membranous obstruction of the left nasal choana, confirming congenital unilateral choanal atresia. In addition, congenital hydrocephalus was detected on CT. Nasopharyngoscopy was performed for confirmation and treatment of choanal atresia.

DIAGNOSIS: Unilateral membranous choanal atresia associated with congenital hydrocephalus.

CLINICAL RELEVANCE: This report describes a rare congenital condition and for the first time, CT imaging provided an accurate diagnosis and allowed planning for the successful treatment of unilateral membranous choanal atresia. In addition, concurrent congenital hydrocephalus was diagnosed.     

Mediastinal lymphoma in a young Turkish Angora cat

An 8-month old intact male Turkish Angora cat was referred to the Veterinary Medical Teaching Hospital (VMTH), Seoul National University, for an evaluation of anorexia and severe dyspnea. The thoracic radiographs revealed significant pleural effusion. A cytology evaluation of the pleural fluid strongly suggested a lymphoma containing variable sized lymphocytes with frequent mitotic figures and prominent nucleoli. The feline leukemia virus and feline immunodeficiency virus tests were negative. The cat was euthanized at his owner''s request and a necropsy was performed. A mass was detected on the mediastinum and lung lobes. A histopathology evaluation confirmed the mass to be a lymphoma. Immunohistochemistry revealed the mass to be CD3 positive. In conclusion, the cat was diagnosed as a T-cell mediastinal lymphoma.     

A Gartner duct cyst of the vagina causing dysuria and dyschezia in a Yorkshire Terrier

A 5 year-old, intact female Yorkshire terrier was referred for dysuria and dyschezia. The radiographic and ultrasound examination showed a round shaped mass caudal to the urinary bladder that contained anechoic fluid within the thin walls. During surgery, the cyst was noted to be attached to the outer wall of the vagina, not connected to the vaginal lumen. Cystic fluid was removed and the cystic wall was resected. Then the remaining cystic wall was omentalized to prevent a recurrence.Histological examination confirmed that the cyst was of Wolffian duct origin. In this case, a large Gartner duct cyst causing urological problems was diagnosed and removed by surgical resection.     

Direct approach to the nasal cavity through a bone flap for the treatment of a large nasal cyst

A 21‐year‐old Warmblood mare was referred to the Equine Department, Vetsuisse Faculty, University of Zurich, because of recurrent unilateral nasal discharge 3 months after partial removal of a large cyst from the left maxillary and frontal sinuses. Endoscopic, radiographic and computed tomographic examinations showed that the remnant of the cyst, which originally had extended from the left maxillary and frontal sinuses into the left nasal cavity, had expanded and was obliterating the left middle nasal meatus. A direct surgical approach to the cyst through the left nasal and maxillary bones rostral to the facial crest was chosen, which allowed evaluation and removal of the entire cyst. Endoscopic examination 3 days post operatively showed no remnants of the cyst, and the mare was discharged in good health. Re‐examination one year later showed no recurrence of the cyst.     

Symptomatic Capillaria plica infection in a young European cat

An 8-month-old owned European cat showing abdominal pain, fever, distended painful bladder and urinary blockage was presented. Intravenous fluids were immediately administered and, after sedation, a urinary catheter was applied. Blood and urine analysis revealed cystitis and a moderate-to-severe degree of renal failure. About 20 thread-like nematodes, identified as Capillaria plica larvae and fragments of adult stages, were found in the urine sediment. After treatment with an oral formulation of fenbendazole at 25 mg/kg q 12 h for 10 days, urinary signs and bladder worms disappeared. Cases of Capillaria species bladder worms in cats are rarely reported and most infected cats show no clinical signs, presumably because of a low parasite burden. In the present study, feline capillariosis was associated to urethral obstruction, severe difficulties in urination, cystitis and renal failures.     

Choledochal cyst with secondary cholangitis,choledochitis, duodenal papillitis,and pancreatitis in a young domestic shorthair cat

Choledochal cysts, congenital segmental dilations of the common bile duct, have been reported in few cats, and histologic characterization is lacking. A 20-mo-old spayed female domestic shorthair cat was presented because of vomiting and weight loss. There was progressive elevation of liver enzyme activity (ALT > ALP, GGT) and hyperbilirubinemia. Diagnostic imaging identified focal cystic dilation of the common bile duct, dilation and tortuosity of adjacent hepatic ducts, and a prominent duodenal papilla. A choledochal cyst was suspected, and the animal was euthanized. On postmortem examination, there was a 2-cm, firm, thickened, cystic dilation of the common bile duct, patent with adjacent ducts. Histologically, the cyst wall was expanded by fibroblasts, collagen, and lymphoplasmacytic inflammation. Adjacent bile ducts were markedly dilated and tortuous, with lymphoplasmacytic inflammation and papillary mucosal hyperplasia that extended to the major duodenal papilla. There was chronic neutrophilic cholangitis, suggesting bacterial infection and/or disturbed bile drainage, extrahepatic obstruction, and lymphoplasmacytic pancreatitis with ductular metaplasia. Prominent lymphoid follicles within biliary ducts and duodenum suggested chronic antigenic stimulation. Choledochal cysts can be associated with chronic neutrophilic cholangitis, extrahepatic obstruction, choledochitis, duodenal papillitis, and pancreatitis, and should be a differential for increased hepatic enzymes and hyperbilirubinemia in young cats.     

Multiple cutaneous histiocytomas in a cat

A 15-year-old domestic long haired cat developed nodular cutaneous masses over the right shoulder that were removed surgically. Similar masses developed in multiple cutaneous sites over the following three years. In each case, the lesions were characterized by diffuse dermal infiltration by histiocytic cells with a low mitotic rate and evidence of epidermotropism. The neoplastic population uniformly expressed class II molecules of the Major Histocompatibility Complex, but did not express the T and B lymphoid markers CD3 and CD79. Perivascular aggregates of CD3⁺ T lymphocytes were located at the deep margins of the tumour nodules. The clinical, histopathological and immunohistochemical features of these tumours are consistent with cutaneous histiocytoma. This tumour has not been previously well-documented in the cat.     

Identification of domestic cat hepadnavirus from a cat blood sample in Japan

The hepatitis B virus (Hepadnaviridae) induces chronic hepatitis and hepatic cancer in humans. A novel domestic cat hepadnavirus (DCH) was recently identified in several countries, however, the DCH infection status of cats in Japan is unknown. Therefore, we investigated the DCH infection rate of 139 cat samples collected in Japan. We identified one positive blood sample (0.78%) from a 17-year-old female cat with chronically elevated alanine aminotransferase. Phylogenetic analysis demonstrated that the DCH strain identified in this study is genetically different from strains in other countries. Further investigations are required to elucidate the evolution of DCH and the impact of DCH infection on hepatic diseases in domestic cats.     

Staphyloma in a cat

A unilateral scleral staphyloma in an 18-month-old, female spayed Domestic Short-haired cat was treated with excision, primary closure and fascial graft. Other ocular abnormalities noted on examination included iris coloboma, anterior cortical cataract, focal lens equator flattening and retinal dysplasia. The staphyloma was presumed to be congenital in origin.     

Nocardial peritonitis in a cat

Objective To illustrate a successfully managed case of nocardial peritonitis in a cat.
Design Case report.
Animal An 8 year old neutered male Burmese cat presented for nonspecific signs of depression, anorexia, pallor and mild dehydration. Pyrexia, loss of weight and abdominal distension developed despite treatment with amoxycillin-clavulanate and supportive therapy.
Procedure Various medical and surgical procedures were used.
Results Haematology revealed severe inflammatory left shift. Biochemistry showed mild prerenal azotemia. A "ground glass" appearance to the abdomen was seen on radiographs. Fluid collected by abdominocentesis contained "sulphur granules" and had characteristics of a septic exudate. Laparotomy allowed drainage of peritoneal fluid and extensive lavage of the peritoneal cavity. Culture of the fluid revealed Nocardia sp. Sensitivity testing resulted in a change of antimicrobial therapy to trimethoprim-sulphadiazine.
Conclusion Response to surgical drainage and change in antibacterial therapy was excellent. No toxic side effects were encountered during the 3 months course of trimethoprim-sulphonamide. The cat made a complete recovery.     

Nasolacrimal obstruction caused by root abscess of the upper canine in a cat

A 10‐year‐old, castrated male domestic short hair cat was presented to the Small Animal Clinic at the Western College of Veterinary Medicine with a presenting complaint of chronic, ocular discharge from the left eye. Ocular examination confirmed epiphora and mucopurulent discharge but there were no apparent reasons for the ocular discharge, and nasolacrimal obstruction was suspected. The cat had swelling of the left side of the face, severe periodontal disease and a fractured upper left canine tooth with pulpal exposure. Dacryocystorhinography revealed narrowing of the nasolacrimal duct above the root of the fractured upper left canine and dental radiographs showed a severe periapical lucency at the apex of the upper left canine tooth. The fractured canine tooth was removed. Subsequently, the ocular discharge and facial swelling resolved. After 2 years, the epiphora has never reoccurred. This is a noteworthy case because a suspected root abscess resulted in extralumenal compression of the nasolacrimal duct, which shows the importance of a thorough oral examination when nasolacrimal obstruction is evident.     

Carcinosarcoma mimicking a feline injection‐site sarcoma in a cat

A 15‐year‐old spayed female domestic short‐haired cat with cutaneous/subcutaneous well‐circumscribed, alopecic mass approximately 25 × 30 mm in diameter, localized to the left shoulder region was brought to the veterinary surgery department. Despite the suggestive location and macroscopic appearance, feline injection‐site sarcoma was not suspected based on the cytologic examination of fine‐needle aspirates. The tumor was surgically resected, and tissue sections were evaluated microscopically. The tumor was found to be nonencapsulated with a distinct border between the neoplastic parenchyma and surrounding connective tissue. The neoplastic tissue consisted of 2 cell populations: elongated to spindle‐shaped cells arranged in bands and cords and malignant epithelial‐like cells. Both populations showed microscopic features of malignancy. Multinucleate giant cells with irregular cytoplasm were scattered among the neoplastic cells. The spindle‐shaped cells strongly expressed vimentin but did not express α‐smooth muscle actin (α‐SMA) or cytokeratin. Desmin was strongly expressed in about 0‐5% of cells. Epithelial‐like cells expressed cytokeratin, but not vimentin, desmin, or α‐SMA. Multinucleate giant cells expressed vimentin, but did not α‐SMA, desmin, or cytokeratin. Based on microscopic observations and IHC results, the final diagnosis was carcinosarcoma with histologic features compatible with feline injection‐site sarcoma, but without the clinical aggressiveness of this tumor.     

B-cell conjunctival lymphoma in a cat

A bilateral conjunctival neoplasm was surgically removed from a 13-year-old Domestic Short-haired female cat and examined by histopathology. The neoplasm was infiltrative, nonencapsulated and composed of large sheets of densely packed, round to polygonal cells. Neoplastic cells were variably sized with scant to modest amounts of cytoplasm and oval to round nuclei. On immunohistochemistry the neoplastic cells stained positively for BLA.36 and negative for CD-3 antibodies. On the basis of histopathology and immunohistochemical findings, a diagnosis of conjunctival B-cell lymphoma was made. This is the first case with immunohistochemical characterization of conjunctival lymphoma in a cat.     

Vitelline cyst in the rat ileum

Congenital vitelline duct anomalies other than Meckel’s diverticulum are rare in animals. A cyst of approximately 8 mm in diameter was observed on the antimesenteric surface of the ileal serosa in a 10-week-old female Crl:CD(SD) rat. Microscopically, the cyst closely resembled the ileum, but it did not communicate with the ileal lumen. We diagnosed this case as a vitelline cyst derived from the vitelline duct based on the location where it developed and its histological behavior. In rats, only Meckel’s diverticulum has been reported with a congenital anomaly of the vitelline duct, and no other spontaneous anomalies including a vitelline cyst have been reported. This case may be the first report concerning a vitelline cyst in the rat ileum.     

Multimodality characterization of a noncommunicating congenital duodenal duplication cyst causing pyloric outflow obstruction in a young dog

A 10‐month‐old German Shepherd Dog presented for evaluation of intermittent vomiting. Abdominal radiographs revealed a marked right cranial mass effect. Initial differentials included abscess/cyst or less likely neoplasia from undetermined origin. On abdominal ultrasound the mass appeared cystic and thin walled. Computed tomography revealed a large cystic lesion originating from the pyloroduodenal junction causing pyloric outflow obstruction. A noncommunicating duodenal duplication cyst was found on exploratory laparotomy and further confirmed with histopathology and immunohistochemistry. Enteric duplication cyst should be considered as a differential in young dogs with gastrointestinal signs and a cystic abdominal mass detected with different imaging modalities.