Improvement in liver pathology after 4 months of D-penicillamine in 5 doberman pinschers with subclinical hepatitis.

Five female Doberman Pinschers with increased hepatic copper concentrations and persistent (3-4 years) subclinical hepatitis were treated with D-penicillamine for 4 months. Before and after treatment, the dogs underwent clinical, hematologic (red blood cell, white blood cell, and differential and thrombocyte counts), and clinical chemistry (creatinine, alkaline phosphatase, alanine aminotransferase, and total bile acid concentrations) examinations, and liver biopsies were examined histologically and their copper content measured quantitatively. No adverse effects were observed during treatment, and CBC and serum chemistry test results did not change. The mean liver copper concentration was 1,036 mg/kg dry matter before treatment and decreased to 407 mg/kg after treatment (P = .03). The copper concentrations had decreased (by between 134 and 1,135 mg/kg dry matter) in all of the dogs. The histopathologic appearance had improved or returned to normal in all 5 dogs. We conclude that D-penicillamine effectively reduced copper retention in these dogs and improved the histopathologic appearance of the lesions. However, because D-penicillamine has both copper-chelating and anti-inflammatory properties, it is not possible to draw conclusions on the etiology of this disease.