Suspected autoimmune hepatitis and primary biliary cirrhosis unmasked by interferon-beta in a multiple sclerosis patient.

The use of interferon-beta in multiple sclerosis is associated with various forms of hepatotoxicity, including autoimmune hepatitis and liver failure. We describe a case with features of autoimmune liver disease and primary biliary cirrhosis occurring during long-term treatment with interferon-beta in a patient with relapsing-remitting multiple sclerosis. This case highlights the importance of monitoring biochemical liver test results throughout interferon-beta treatment of multiple sclerosis.