Phenprocoumon-induced necrotizing hepatitis

Clinical presentation: A 52-year-old female patient presented at our hospit al with right upper abdominal pain and impaired general condition. During t he previous 7 months, the patient had received anticoagulation treatment wi th phenprocoumon due to a prosthetic aortic Valve replacement. Tests: Serological tests for virologic, autoimmune or metabolic causes of h epatitis were negative. The histologic examination of liver biopsies showed necrotizing hepatocellular injury in zone 3 of the acinus without relevant fibrosis. Initially, a lymphocyte transformation test with phenprocoumon w as negative. A second test after one week turned out to be positive. Diagnosis and clinical course: After withdrawal from phenprocoumon therapy and switching to anticoagulation with a low molecular weight hepa rin, live r tests gradually became normal. Aminotransferase levels rapidly increased when phenprocoumon treatment was resumed. Phenprocoumon-associated necrotiz ing hepatitis was diagnosed by clinical course, liver histology and the pos itive lymphocyte transformation test. After immunosuppressive treatment wit h prednisolone was started again, liver enzymes gradually normalized. Antic oagulation was further performed with low molecular weight heparin. Conclusion: This case stresses the fact that an adequate and detailed histo ry on concomitant medication is mandatory in patients who present with cryp tic hepatitis. Though severe hepatic adverse effects of phenprocoumon are r are, physicians should consider coumarin derivatives as a potential source of hepatitis.