Hemochromatosis of unknown origin in a young adult dog.

Hemochromatosis is an uncommon condition in dogs. This report describes hemochromatosis of unknown origin in a dog breed not previously identified as predisposed to the condition. A 3-year-old spayed female German shepherd crossbred dog was presented to a local Saskatchewan veterinary clinic with weight loss, muscle wasting, chronic vomiting, diarrhea, and ascites of ~5 to 6 mo duration. The dog was treated symptomatically and was prescribed medication for potential liver failure. Due to poor response to treatment, the owners elected humane euthanasia. The dog was submitted for necropsy at Prairie Diagnostic Services (Western College of Veterinary Medicine, Saskatoon, Saskatchewan). Necropsy revealed hepatic cirrhosis indicated by severe portal bridging fibrosis and nodular regeneration with iron accumulation (hemosiderin) within the hepatocytes and Kupffer cells. Hemosiderin granules were also identified within the lymph nodes, pancreas, and kidneys. Toxicology testing revealed a highly elevated hepatic iron concentration that was subsequently interpreted as toxic (6479 ppm, wet weight basis). A diagnosis of hemochromatosis was made based on clinical history, gross necropsy findings, elevated hepatic iron concentration, and parenchymal hemosiderin deposition pattern in the liver. Given the lack of chronic exposure to iron, primary hemochromatosis was suspected. An underlying genetic cause was a possible etiology. Key clinical message: This case demonstrates the potential of hemochromatosis as a differential diagnosis for chronic liver disease. Due to currently limited noninvasive antemortem testing options and the potential for development of hepatic cirrhosis, early diagnosis and treatment of hemochromatosis is challenging.