Hepatic insufficiency in two juvenile dogs with histoplasmosis.

A 9-month-old female intact toy poodle and a 1-year-old female intact Labrador retriever mix presented to separate teaching hospitals for chronic histories of malaise and clinicopathologic evidence of hepatic dysfunction. The signalment and clinical histories of these dogs prompted consideration of a congenital portosystemic shunt as a primary differential. However, microscopic evaluation of peritoneal effusion, pleural effusion, and peripheral blood samples from the dogs revealed round to ovoid yeast organisms morphologically most compatible with Histoplasma capsulatum. Additional testing confirmed histoplasmosis in each case. The poodle underwent a computed tomography (CT) study, which showed hepatomegaly with a spleno-gonadal shunt, pancreatic and gastric wall edema, and marked peritoneal effusion, findings compatible with portal hypertension and secondary acquired shunt formation. The dog was later humanely euthanized due to clinical deterioration, and on necropsy hepatic histoplasmosis was verified, with additional affected tissues comprising lungs and spleen. The Labrador Retriever mix responded clinically and clinicopathologically to antifungal therapy, though no abdominal imaging was performed to definitively exclude the possibility of a congenital portosystemic shunt. In retrospect, several features were more compatible with histoplasmosis than portosystemic shunt in these cases, including hyperbilirubinemia, effusion, and hepatomegaly. These findings serve as a reminder of the need to interpret serum biochemical findings in the context of the totality of the clinicopathologic data and imaging findings, as well as the diagnostic value of microscopy in the evaluation of hematologic and body cavity fluid samples.

Radiographic and ultrasonographic appearance of a jejunal torsion-volvulus in a dog.

A 1.5-year-old male neutered, 5 kg, Dachshund was referred for anorexia and vomiting for several days' duration. Radiographs revealed concern for a small intestinal obstruction. Ultrasonography revealed a severely distended segment of jejunum containing echogenic fluid that abruptly narrowed, twisted, and transitioned into normal jejunum, along with the presence of a distinct "whirl sign" that resulted from the intestinal segments twisting around themselves. This, in addition to the absence of flow on power Doppler interrogation, was compatible with a focal jejunal torsion-volvulus. The torsion-volvulus was surgically confirmed, a resection and anastomosis was performed, and the dog recovered uneventfully.