Autoimmune Hepatitis Triggered by Treatment With Pegylated Interferon α-2a and Ribavirin for Chronic Hepatitis C.

Hepatitis flare is rarely observed during treatment with pegylated interferon alpha for hepatitis C virus (HCV) infection. A 49-year-old man receiving pegylated interferon α-2a for HCV infection had icterus and hyperbiliru-binemia in the 14th week of therapy, with HCV RNA undetectable after the 12th dose. Liver biopsy was suggestive of chronic hepatitis with cirrhosis without interface pattern. Pegylated interferon was discontinued; a few weeks later, his aminotransferases and immunoglobulin levels increased significantly. Antibody to cytosolic liver antigen-1 was positive, and liver biopsy revealed lymphoplasmacytic infiltrate with intense interface hepatitis, consistent with autoimmune hepatitis.