Evaluation of serum ferritin as a tumor marker for canine histiocytic sarcoma.

BACKGROUND: Canine histiocytic sarcoma (HS) is an aggressive malignancy. Hyperferritinemia has been documented in dogs with HS and could serve as a tumor marker aiding in diagnosis and treatment. In people, hyperferritinemia is found in inflammatory diseases, liver disease, and hemolysis, and thus may occur in dogs with these conditions. OBJECTIVE: To determine if serum ferritin concentration is a tumor marker for canine HS. ANIMALS: Dogs with HS (18), inflammatory diseases (20), liver disease (24), immune-mediated hemolytic anemia (IMHA) (15), and lymphoma (23). METHODS: Prospective, observational, cohort study: Serum ferritin concentration was measured at initial diagnosis. Parametric methods were used to compare mean log ferritin concentrations among disease categories. Receiver-operating characteristic curves and likelihood ratios were used to evaluate serum ferritin concentration as a tumor marker. RESULTS: Varying proportions of dogs with IMHA (94%), HS (89%), liver disease (79%), lymphoma (65%), and inflammatory diseases (40%) had hyperferritinemia. Dogs with IMHA had significantly higher mean ferritin concentration than dogs in all other categories. Dogs with HS had significantly higher mean ferritin concentration than those in the inflammatory disease and lymphoma categories. Mean serum ferritin concentration was not significantly different between dogs with HS and those with liver disease. Decision thresholds were determined to distinguish IMHA and HS from the other diseases associated with hyperferritinemia. CONCLUSION: Hyperferritinemia is common in dogs with HS and, after IMHA is ruled out, the degree of hyperferritinemia may be useful in differentiating dogs with HS from dogs with inflammatory diseases, liver disease, and lymphoma.

Juvenile pancreatic atrophy in Greyhounds: 12 cases (1995-2000).

BACKGROUND: This study describes compound failure of the endocrine and exocrine pancreas in Greyhounds, a condition that has not been reported in the veterinary literature. OBJECTIVE: To describe the clinical and pathologic findings in 12 Greyhounds with juvenile pancreatic atrophy. ANIMALS: Ten Greyhounds presented for necropsy examination and 2 sibling Greyhounds presented for clinical evaluation before necropsy, all with a history of small-bowel diarrhea. PROCEDURES: Retrospective study of laboratory and pathologic findings in 12 Greyhounds, including serum trypsin-like immunoreactivity assays, oral glucose tolerance testing, and serum anti-insulin antibody concentrations. RESULTS: Gross pancreatic atrophy was found in all 12 dogs. Histopathologic lesions were found in both the endocrine and exocrine pancreas and included acinar cell apoptosis, zymogen granule loss, cytoplasmic clearing or vacuolar change, lobular atrophy, islet loss, and lymphocytic or lymphoplasmacytic pancreatitis. Antemortem test results on the 2 Greyhound puppies indicated concurrent exocrine pancreatic insufficiency (EPI) and insulin-dependent diabetes mellitus (IDDM). CONCLUSIONS AND CLINICAL IMPORTANCE: Compound failure of the exocrine and endocrine pancreas is rarely reported in dogs and neither disease is well recognized in the Greyhound. This condition is of potential economic importance to the Greyhound racing industry.

Intracardiac ectopic thyroid carcinosarcoma in a dog.

A 13-year-old spayed female Labrador Retriever with a 1-year history of progressive exercise intolerance was diagnosed with an interventricular mass in the heart via echocardiogram. The animal's general condition progressively declined over the next 8 months, and it was euthanatized. The intracardiac mass, which protruded into the lumen of the right ventricle, was removed at necropsy and fixed in 10% buffered formalin. Histopathologic diagnosis was an ectopic thyroid carcinosarcoma based on the presence of 3 distinct neoplastic tissue types. Intermixed within the tumor were neoplastic thyroid follicles containing colloid and solid nests of thyroid follicular epithelial cells, vascular channels and clefts filled with blood and lined by neoplastic endothelium, and osteoid surrounded by spindle cells and often rimmed by large multinucleated cells. Immunohistochemical reaction for thyroglobulin was positive in the tumor cells forming the colloid-filled follicles and solid nests of epithelial cells. Neoplastic endothelium was positive for factor VIII-related antigen. The thyroid gland was located in its normal anatomic position and was histologically normal, ruling out the possibility that the intracardiac tumor was a metastatic lesion. To the authors' knowledge this is the first reported case of an intracardiac ectopic thyroid carcinosarcoma, and possibly the first ectopic thyroid carcinosarcoma in any location in any species.

Effects of steroidal implantation and ractopamine-HCl on nitrogen retention, blood metabolites and skeletal muscle gene expression in Holstein steers.

Six Holstein steers (231 +/- 17 kg) housed in metabolism crates were used in a randomized complete block design with three blocks of two steers based on previous serum insulin-like growth factor (IGF)-I concentrations. One of the two steers in each block was implanted with 120 mg trenbolone acetate and 24 mg oestradiol-17beta on day 0. None of the steers was fed ractopamine-HCl in the initial 28 days, and then all steers were fed 200 mg of ractopamine-HCl per steer daily from day 28 until the end of the trial. Steers were fed a corn-based diet (62% rolled corn, 20% expeller soya bean meal and 15% alfalfa hay) twice daily with an average dry matter intake of 4.8 kg/day. Blood and M. longissimus biopsy samples were collected prior to implantation and on days 14, 28, 42 and 56. There was an implant x ractopamine interaction for retained nitrogen (p < 0.05); ractopamine feeding led to only small improvements in nitrogen retention for implanted steers (45.9 g/day vs. 44.5 g/day), whereas ractopamine led to larger increases in nitrogen retention for non-implanted steers (39.0 g/day vs. 30.4 g/day). Implantation increased (p < 0.05) and ractopamine tended to decrease (p = 0.06) serum IGF-I concentrations. Implantation tended to increase (p = 0.16) and ractopamine decreased (p < 0.05) mRNA expression of IGF-I in the M. longissimus. Ractopamine decreased mRNA expression of beta(1)- and beta(2)-receptors in M. longissimus (p

Fibrosarcoma over the tarsal groove of a 14-month-old Quarter horse.

A 14-month-old male Quarter horse was presented for evaluation of a grade 3 out of 5 (grade 0 = sound; grade 5 = non-weight bearing) right rear lameness. A firm, 8 x 16 cm mass was palpable at the caudal medial aspect of the distal tibia and proximal tarsal region of the right hind limb. A percutaneous needle aspirate contained mesenchymal cells that were moderate to large in size with single, oblong nuclei. Differential diagnoses included fibrous hyperplasia, fibroma, or well-differentiated fibrosarcoma. Excisional biopsy for both definitive diagnosis and treatment was offered and selected by the owner. A fibrosarcoma was confirmed by histological examination of the mass. One and a half years after resection signs of lameness or evidence of regrowth of the mass were not evident.

Hepatotoxicity of stanozolol in cats.

OBJECTIVE: To determine hepatotoxicity of stanozolol in cats and to identify clinicopathologic and histopathologic abnormalities in cats with stanozolol-induced hepatotoxicosis. DESIGN: Clinical trial and case series. ANIMALS: 12 healthy cats, 6 cats with chronic renal failure, and 3 cats with gingivitis and stomatitis. PROCEDURES: Healthy cats and cats with renal failure were treated with stanozolol (25 mg, i.m., on the first day, then 2 mg, p.o., q 12 h) for 4 weeks. Cats with gingivitis were treated with stanozolol at a dosage of 1 mg, p.o., every 24 hours. RESULTS: Most healthy cats and cats with renal failure developed marked inappetence, groomed less, and were less active within 7 to 10 days after initiation of stanozolol administration. Serum alanine transaminase (ALT) activity was significantly increased in 14 of 18 cats after stanozolol administration, but serum alkaline phosphatase activity was mildly increased in only 3. Four cats with serum ALT activity > 1,000 U/L after only 2 weeks of stanozolol administration had coagulopathies; administration of vitamin K resolved the coagulopathy in 3 of the 4 within 48 hours. All 18 cats survived, and hepatic enzyme activities were normal in all cats tested more than 4 weeks after stanozolol administration was discontinued. Two of the 3 cats with gingivitis developed evidence of severe hepatic failure 2 to 3 months after initiation of stanozolol treatment; both cats developed coagulopathies. Histologic evaluation of hepatic biopsy specimens from 5 cats revealed diffuse hepatic lipidosis and cholestasis without evidence of hepatocellular necrosis. CONCLUSIONS AND CLINICAL RELEVANCE: Results suggest that stanozolol is hepatotoxic in cats.

Primary hemangiosarcoma of the iliopsoas muscle eliciting a peripheral neuropathy.

An eight-year-old, male castrated bullmastiff presented to the Kansas State University Veterinary Medical Teaching Hospital with left hind-limb paralysis. A mass was identified in the left paralumbar soft tissue adjacent to the fourth (L4) to sixth (L6) lumbar vertebrae by magnetic resonance imaging. The iliopsoas muscle contained the mass which was identified as a hemangiosarcoma on histopathological examination. Hemangiosarcoma is rarely reported as a primary tumor arising from muscle vascular endothelium.

Production, characterization, and uses of monoclonal antibodies against recombinant nucleoprotein of elk coronavirus.

This is the first report of the production of monoclonal antibodies against elk coronavirus. The nucleoprotein gene of elk coronavirus was amplified by PCR and was cloned and expressed in a prokaryotic expression vector. Recombinant nucleocapsid protein was used to immunize mice for the production of hybridomas. Twelve hybridomas that produced monoclonal antibodies against the nucleocapsid protein of elk coronavirus were selected by an indirect fluorescent-antibody test, an enzyme-linked immunosorbent assay, and a Western blot assay. Ten of the monoclonal antibodies were of the immunoglobulin G1 (IgG1) isotype, one was IgG2a, and one was IgM. All had kappa light chains. By immunohistochemistry four monoclonal antibodies detected bovine coronavirus and elk coronavirus in formalin-fixed intestinal tissues. Antinucleoprotein monoclonal antibodies were found to be better at ruminant coronavirus detection than the anti-spike protein monoclonal antibodies. Because nucleoprotein is a more abundant antigen than spike protein in infected cells, this was not an unexpected finding.

An ovarian teratoma in a cat.

A 5-month-old, intact female, domestic shorthaired cat was presented for evaluation of abdominal distension. Abdominal radiographs revealed a midabdominal mass that contained multiple, irregular, mineralized opacities. The mass was surgically removed, and an ovariohysterectomy performed. The mass was located at the tip of the left uterine horn and was covered partially by haired skin. Histologically, the mass was diagnosed as a mature ovarian teratoma based on the presence of well-differentiated somatic structures derived from three primary embryonal germ-cell layers. Germ-cell tumor classification and feline ovarian teratomas are reviewed.

Immunohistochemistry of pancreatic islet cell tumors in the ferret (Mustela putorius furo).

Twenty-two pancreatic islet cell tumors and normal pancreatic islets from ferrets were evaluated by immunohistochemistry for expression of the peptide hormones insulin, somatostatin, glucagon, and pancreatic polypeptide (PP) and the neuroendocrine markers chromogranin A (CgA) and neuron-specific enolase (NSE). In normal pancreatic islets, the majority of cells stained strongly with CgA and NSE. A cells, B cells, D cells, and PP cells stained strongly with glucagon, insulin, somatostatin, and PP, respectively. All 22 tumors stained with CgA and NSE. The proportion of cells within tumors staining for CgA was variable, but more than half of the cells stained positively in 18 of the tumors. The intensity of staining for CgA was strongly (reactivity equivalent to or greater than normal islet cells in adjacent tissue) in 11 moderate in six, and weak in five of the tumors. All tumors stained for NSE, with > or = 50% of the cells staining in 21 of the tumors, and the intensity of staining was strong in 18 of the tumors. Twenty of 22 tumors stained positively for insulin. with > or = 50% of the cells staining in 19 of them. The intensity of staining for insulin was strong in 12, moderate in seven, and weak in one of the tumors. Approximately < or = 1% of the cells in 15 of 22 tumors stained for somatostatin, five tumors stained for pancreatic polypeptide, and three tumors stained for glucagon. These data indicate that the majority of islet cell tumors of ferrets express immunohistochemically detectable insulin. CgA and NSE are both useful general markers for such tumors, including those that are insulin negatives. Commercially available antisera to CgA, NSE, insulin, glucagon, somatostatin, and PP work well in formalin-fixed, paraffin-embedded tissue for immunophenotyping islet cell tumors in the ferret.

Respiratory diagnostic pathology.

Effective treatment and control of bovine respiratory disease is dependent upon an accurate diagnosis. This article discusses the approach to diagnosis of bovine respiratory disease from the perspective of respiratory pathology. Topics covered include necropsy examination of the respiratory system, sample collection and submission, and the gross, and histopathologic lesions of the upper and lower bovine respiratory system.

Application of immunohistochemistry and in situ hybridization for detection of bovine coronavirus in paraffin-embedded, formalin-fixed intestines.

A monoclonal antibody (MAb) (Z3A5) against spike protein subunit of bovine coronavirus (BCV) reacted with the virus in formalin-fixed intestines in an immunoperoxidase test. We found an 88% correlation between immunohistochemistry with Z3A5 and in situ hybridization with a BCV nucleoprotein cDNA probe. MAb Z3A5 reacted with 90 BCV isolates from the United States and was an effective reagent for the diagnosis of BCV.

Chromogranin A plasma concentration and expression in pancreatic islet cell tumors of dogs and cats.

OBJECTIVES: To describe expression of the neuroendocrine marker chromogranin A (CgA) in canine and feline pancreatic islet cell tumors and their metastases, and to evaluate plasma CgA concentration in dogs and cats with insulinoma. SAMPLE POPULATION: Paraffin-embedded tissues from 25 canine and 2 feline pancreatic islet cell tumors, 5 canine and 6 feline exocrine pancreatic tumors, and normal pancreatic tissue from 2 dogs and 2 cats. Heparinized plasma samples from 3 dogs and 2 cats diagnosed with insulinoma, and 10 control plasma samples from each species. PROCEDURE: Immunohistochemical analysis was performed on the 42 tissue specimens, using antisera against CgA, neuron-specific enolase, insulin, somatostatin, glucagon, and pancreatic polypeptide. The 25 plasma samples were evaluated, using a soluble-phase, double-antibody, equilibrium radioimmunoassay directed against the amino- and carboxy-terminal peptides of bovine CgA. RESULTS: Chromogranin A expression was found in 76% of canine and 2 of 2 feline pancreatic islet cell tumors. Of 7 animals with CgA immunoreactivity in primary tumors, 6 also had CgA immunostaining of metastatic lesions. Plasma CgA concentration in 2 dogs with insulinoma (0.9, 1.0 ng/ml) exceeded the reference range established for 10 clinically normal control dogs (0.50 +/- 0.16 ng/ml). Feline plasma CgA samples had extensive nonspecific background immunoreactivity. CONCLUSIONS: Chromogranin A is a useful immunohistochemical marker for pancreatic tumors of neuroendocrine origin and their metastases. Plasma CgA concentration determined by radioimmunoassay was high in 2 dogs with insulinoma. CLINICAL RELEVANCE: Immunohistochemical staining of tissues or cytologic specimens for CgA and/or neuron-specific enolase may help distinguish masses of unknown origin as neuroendocrine in nature. Increase in plasma CgA concentration may be useful diagnostically for animals with suspected neuroendocrine tumors.

Enzyme-linked immunosorbent assay to measure serum ferritin and the relationship between serum ferritin and nonheme iron stores in cats.

Serum ferritin concentration correlates with tissue iron stores in humans, horses, calves, dogs, and pigs but not in rats. Because serum iron and total iron-binding capacity can be affected by disorders unrelated to iron adequacy (such as hypoproteinemia, chronic infection, hemolytic anemia, hypothyroidism, and renal disease), serum ferritin is probably the most reliable indicator of total body iron stores in larger species. To test the hypothesis that serum ferritin might be correlated with tissue iron levels in cats, we developed a quantitative enzyme-linked immunosorbent assay that uses two monoclonal antibodies in a sandwich arrangement to measure feline serum ferritin. The recovery of purified ferritin added to feline sera ranged from 94% to 104%; the within-assay coefficient of variability was 8.4%, and the assay-to-assay variability was 13.2%. Mean serum ferritin from 40 apparently healthy cats was 76 ng/ml (SD = 24 ng/ml). Serum ferritin concentration was significantly correlated (P < 0.001, n = 101, r = 0.365) with the nonheme iron in the liver and spleen (expressed as milligrams of iron per kilogram of body weight), as determined by Pearson product-moment correlation analysis. Because serum iron can decrease in diseases other than iron deficiency, the combination of serum iron and serum ferritin should provide sufficient evidence to differentiate anemia of chronic inflammation from anemia of iron deficiency in the cat.

Reactivity of lichen lectins with blood typed canine erythrocytes.

Extracts from 69 species of lichens were tested for their ability to agglutinate untreated and enzyme-modified erythrocytes from a panel of blood typed dogs. Forty-three lichen species reacted positively with either untreated or enzyme-modified cells. Many extracts exhibited differential agglutination among red cells tested. The patterns of differential agglutination observed with the lichen extracts did not correspond to known canine blood groups present on the test red cell panel.

Production, characterization, and applications of a murine monoclonal antibody to dog erythrocyte antigen 1.1.

A murine IgM monoclonal antibody, which recognizes dog erythrocyte antigen (DEA) 1.1, has been produced. The antibody correctly identified canine RBC possessing DEA 1.1 in a panel of RBC typed by an independent laboratory. Reactivity of the monoclonal antibody was compared with canine anti-DEA 1.1 antiserum with 163 RBC samples from 145 dogs. Results of agglutination tests with the 2 reagents were in agreement for all samples. A card agglutination test that uses the monoclonal antibody with blood is described. A monoclonal antibody-based test should facilitate blood typing for DEA 1.1 in clinical practice.

N-glycolylneuraminic acid and N-acetylneuraminic acid define feline blood group A and B antigens.

Blood group incompatibility causes transfusion reactions and neonatal isoerythrolysis in cats. We investigated the molecular nature of the blood group antigens from cats that had blood type A, B, and AB erythrocytes. Naturally occurring anti-type B antibodies, Triticum vulgaris lectin, monoclonal antibody (MoAb) 32-27, and MoAb R-24 were used in agglutination tests, Western blots, and thin-layer chromatography (TLC) enzyme immunostaining. Type A erythrocytes had NeuGc-NeuGc-Galactose-Glucose-Ceramide ([NeuGc]2GD3) where NeuGc represents N-glycolylneuraminic acid, and NeuAc-NeuGc-GD3, where NeuAc represents N-acetylneuraminic acid, and may have [NeuGc]2 disialylparagloboside and NeuAc-NeuGc-disialylparagloboside. Type B erythrocytes only had [NeuAc]2GD3. Type AB erythrocytes had [NeuGc]2GD3, NeuAc-NeuGc-GD3, and [NeuAc]2GD3. Blood group antigens were also found on a 50-Kd membrane protein. We conclude that type B erythrocytes are characterized by [NeuAc]2GD3 as the only form of this ganglioside and the presence of NeuAc on a 50-Kd membrane protein. NeuGc is the major determinant of the A antigen; specifically, [NeuGc]2GD3 is the major glycolipid form. The A antigen is also present on a 50-Kd membrane protein.