Angela B. Royal

Cytologic and Histopathologic Evaluation of Extruded Canine Degenerate Disks

OBJECTIVE To describe the cytologic and histopathologic appearance of degenerate disk material in dogs with Hansen type I intervertebral disk disease (IVDD). STUDY DESIGN Case series. ANIMALS Dogs (n=45) that had surgical intervention for Hansen type I IVDD (January-November 2007). METHODS Impression smears and histopathologic sections were prepared from surgically removed degenerate disk material. All slides were evaluated for overall cellularity, quantity and attributes of extracellular matrix, types of cells present, and their cytomorphology. Histopathologic sections were also examined for presence of neovascularization and hemorrhage. RESULTS Cytologically, 11 of 45 samples consisted of only extracellular matrix, 30 had evidence of inflammation, and 20 contained dysplastic spindloid cells. Histologically, hyaline cartilage predominated in 35 of 45 samples, fibrocartilage in 4, and spindloid cells in 6; 37 of 45 were inflamed, 37 were hemorrhagic, and 13 had neovascularization. CONCLUSIONS The cytologic and histopathologic appearance of extruded degenerate disk material in dogs is variable and can include dysplastic spindloid cells. CLINICAL RELEVANCE The variability in cytologic findings and frequent presence of dysplastic spindloid cells suggest that cytology alone may not be a reliable tool to differentiate degenerate canine disk material from a mesenchymal neoplasm.

Disseminated Melanoma in a Dog with Involvement of Leptomeninges and Bone Marrow

An 11-year-old, Black and Tan Coonhound dog was presented with a history of lameness of the right hind leg for 2 months, osteolysis in the right distal femur, a pulmonary mass, and a presumptive diagnosis of osteosarcoma. By cytologic examination, neoplastic melanocytes were noted from fine needle aspirates of the femoral and pulmonary masses. Postmortem examination revealed a disseminated melanoma involving the right femoral bone marrow, lung, multiple lymph nodes, and adrenal gland, with diffuse infiltration of the leptomeninges of the brain and spinal cord. This case report describes a unique presentation of canine melanoma, which in some ways resembles leptomeningeal melanomatosis, a rare human melanoma variant.

What is your diagnosis? Blood film from a boa constrictor

An adult female common northern boa constrictor (Boaconstrictor imperator) of unknown age and weighing 5.5 kgwas presented to the West Esplanade Veterinary Clinic,Metairie, LA for a 4-month history of anorexia and weightloss. Two other boa constrictors housed in close proximityto the ill snake had recently died after a period of anorexiaof unknown duration. On physical examination, the snakewas thin with a body condition score of 2/5; excess gas wasnoted on abdominal palpation. Blood was collected by car-diocentesis and placed in a heparinized tube. Freshly madeblood films and the tube were submitted for analysis to theClinical Pathology Laboratory at the Louisiana State Uni-versity School of Veterinary Medicine. Owing to markedlymphocytosis, the total WBC count obtained by enumerat-ing cells in a hemocytometer chamber was deemed inaccu-rate, because it is based on counting heterophils andeosinophils, and then calculating the total WBC countbased on differential percentages. A Wright–Giemsa-stainedblood film was examined (Figure 1). The estimated totalWBC was 40.0 9 10

Concurrent thoracic mesothelioma and thyroid C-cell adenoma with amyloid deposition in an aged horse

Abstract A 21‐year‐old American Saddlebred mare died with a history of weight loss and breathing difficulties of 1 month duration. Post‐mortem examination revealed a copious pleural effusion with multifocal to coalescing numerous white to grey nodular masses on the serosal surface of the pericardium, lungs and thoracic cavity. In addition, the left thyroid gland was markedly enlarged. A thoracic mesothelioma and C‐cell adenoma with amyloid deposits of the left thyroid gland were diagnosed by histopathology and confirmed by immunohistochemistry employing antibodies against cytokeratin (CK), vimentin and calcitonin. Amyloid deposits in the thyroid tumour were confirmed by Congo red staining with apple‐green birefringence under polarized light. Mesothelioma remains an uncommon neoplasm encountered in aged horses. Discussion includes the diagnostic challenge of differentiating carcinomatosis from mesothelioma by histology and differentiating reactive and neoplastic mesothelial cells by cytology.

Immune complex glomerulonephritis of suspected iatrogenic origin in five Japanese Black calves

Five Japanese Black embryo transfer calves from a single embryo flush, 30 to 45-days-old, including 4 live animals for clinical examination and 1 dead for necropsy, were presented with a history of decreased milk intake and hypoproteinemia. Consistent clinicopathological abnormalities in the 4 calves presented for clinical evaluation included hyperkalemia, hyperphosphatemia, hypoproteinemia, hypoalbuminemia, hyperbilirubinemia, increased creatine phosphokinase activity, and proteinuria. Four calves ultimately were necropsied and all had histologic evidence of immune complex glomerulonephritis. Glomerulonephritis in these calves was hypothesized to have resulted from the interaction of passively acquired antibodies at birth and active immunization at 7 and 28 days of age with a Salmonella Typhimurium core antigen vaccine.

What is your diagnosis? Pancreatic aspirate from a cat

A 5-year-old, spayed female Domestic Shorthaired cat was presented to the referring veterinarian for a 4-day history of anorexia, painful abdomen, and repetitive gagging. No laboratory data were generated. Abdominal radiographs revealed gas distension in the stomach and intestinal loops. The cat underwent abdominal exploratory surgery. Upon surgical evaluation, the intestinal tract appeared normal; however, the tail of the pancreas was noticeably thickened, nodular, and dark brown to black. This affected region was firm on palpation and approximately 3 times the thickness of the adjacent normal pancreatic tissue. Dark viscous material was aspirated from the pancreatic nodules and several direct smears were prepared. All slides were submitted to the University of Missouri–Columbia, Veterinary Medical Diagnostic Laboratory cytology service for review (Figure 1).

Mycobacterium Fortuitum Lipoid Pneumonia in a Dog

A 1-year old female spayed German Shepherd dog was evaluated for acute onset of dyspnea. Pyogranulomatous inflammation and green globoid structures were present on aspirates of the affected lung. Impression smears and histopathology confirmed pyogranulomatous pneumonia, with large amounts of lipid corresponding to the green structures noted cytologically, and identified poorly staining bacterial rods within lipid vacuoles. Special stains confirmed the presence of acid-fast bacterial rods, and polymerase chain reaction and DNA sequencing identified the organism as Mycobacterium fortuitum. M. fortuitum pneumonia is well described in humans and has previously been reported in 4 dogs and 1 cat. Lipid was a prominent cytologic and histologic feature, as is often described in humans and in the single feline case report. Additionally, this case highlights the variable cytologic appearance of lipid, as well as Mycobacterium spp, which are classically nonstaining with Wright-Giemsa.