title: Idiosyncratic drug allergic phenprocoumon-induced hepatitis with subacute liver failure initially misdiagnosed as autoimmune hepatitis.
abstract: BACKGROUND
  Coumarin anticoagulants are known to cause hepatotoxicity, but only a few cases have been reported. Coumarins are usually administered following cardiovascular surgery and the differential diagnosis is post-transfusion hepatitis.
  
  
  METHODS
  We report the case of a 46-year-old woman who presented with jaundice, elevated liver function tests, positive antinuclear and smooth muscle antibodies following prodromal signs of fatigue and nausea. The patient had been treated with phenprocoumon for 5 months in order to prevent thromboembolism after two strokes assumed to be due to an open foramen ovale and an aneurysmatic atrial septum.
  
  
  RESULTS
  There was no evidence of viral or other causes of hepatitis. The patient rapidly developed subacute liver failure with encephalopathy and phenprocoumon treatment was stopped. With intensive care support, as well as high-dose prednisolone treatment, she recovered. Owing to positive antinuclear and smooth muscle antibodies, the initial diagnosis 'acute autoimmune hepatitis with liver failure was made.
  
  
  CONCLUSIONS
  The lack of hypergammaglobulinaemia and the rapid recurrence of hepatitis following re-exposure to phenprocoumon led to the final diagnosis of phenprocoumon-induced idiosyncratic drug allergic hepatitis with secondary autoimmune phenomena.
authors.affiliation: First Dept. of Medicine, Christian-Albrechts-University, Kiel, Germany. hhinrichsen@1med.uni-kiel.de
authors.forename: H
authors.initials: H
authors.lastname: Hinrichsen
authors.forename: J
authors.initials: J
authors.lastname: Lüttges
authors.forename: G
authors.initials: G
authors.lastname: Klöppel
authors.forename: U R
authors.initials: UR
authors.lastname: Fölsch
authors.forename: W E
authors.initials: WE
authors.lastname: Schmidt
mesh_terms: D000893:Anti-Inflammatory Agents / Q000627:therapeutic use; D000925:Anticoagulants / Q000009:adverse effects*; D001706:Biopsy; D056486:Chemical and Drug Induced Liver Injury / Q000175:diagnosis* / Q000188:drug therapy / Q000209:etiology*; D003951:Diagnostic Errors; D004342:Drug Hypersensitivity / Q000175:diagnosis* / Q000209:etiology*; D005260:Female; D006322:Heart Aneurysm / Q000150:complications; D006344:Heart Septal Defects, Atrial / Q000150:complications; D019693:Hepatitis, Autoimmune / Q000175:diagnosis*; D006801:Humans; D017093:Liver Failure / Q000139:chemically induced* / Q000175:diagnosis* / Q000188:drug therapy; D008111:Liver Function Tests; D008875:Middle Aged; D010644:Phenprocoumon / Q000009:adverse effects*; D011239:Prednisolone / Q000627:therapeutic use; D012008:Recurrence; D020521:Stroke / Q000209:etiology / Q000517:prevention & control; D013923:Thromboembolism / Q000209:etiology / Q000517:prevention & control; D013997:Time Factors
chemical_list: D000893:Anti-Inflammatory Agents; D000925:Anticoagulants; D011239:Prednisolone; D010644:Phenprocoumon