Primary biliary cirrhosis induced by interferon-alpha therapy for hepatitis C virus infection.

Interferon-alpha is known to exacerbate and in some cases induce a variety of autoimmune disorders. In this report we describe the onset of primary biliary cirrhosis in a 55-year-old woman without evidence of preexisting autoimmune diseases receiving recombinant interferon-alpha 2a for chronic active hepatitis C. Shortly after discontinuing interferon therapy, alkaline phosphatase levels started to rise up to three times the normal range. Anti-mitochondrial antibodies were found to be positive at a high titer, and liver biopsy showed a picture of chronic active hepatitis along with primary biliary cirrhosis features (overlap syndrome). Primary biliary cirrhosis should be considered in the differential diagnosis in any patient treated with interferon-alpha with unexplained elevation of serum alkaline phosphatase.