Drug-induced hepatitis: a rare complication of oral anticoagulants

Hepatotoxicity is a rare complication of coumarin anticoagulants. We present the case of a 56-year-old woman who developed a viral-hepatitis-like picture 8 months after mitral valve replacement and oral anticoagulation. Phenprocoumon-induced hepatitis was diagnosed after positive reexposure and improvement following withdrawal of the drug. There appeared to be cross-reactivity to warfarin since this drug led to a similar increase in alkaline phosphatase and gamma-glutamyl transferase after a few days of administration. Liver biopsy showed an acute viral-hepatitis-like picture. Anticoagulation was changed to a subcutaneous low molecular weight heparin and low-dose aspirin. Because of the widespread use of coumarin anticoagulants, physicians should be aware of the hepatotoxic potential of these drugs, which most frequently mimics the clinical presentation of viral hepatitis.