Acquired hemophilia A in a patient with systemic lupus erythematosus

A patient with systemic lupus erythematosus (SLE) developed acquired hemoph ilia A. The patient, a 24-year-old Japanese woman, was referred to our hosp ital because of uncontrollable bleeding following a tooth extraction. Labor atory examination revealed prolonged APTT (116 seconds), reduced factor VII I activity (2.8 %) and the presence of factor VIII inhibitor at a titer of 46.5 Bethesda units/ml. Transfusion of prothrombin complex concentrate and activated prothrombin complex concentrate followed by administration of pre dnisolone and cyclophosphamide successfully arrested bleeding and reduced t he factor VIII inhibitor level. Acquired hemophilia A is a rare but lethal condition. Rapid diagnosis and introduction of adequate therapies are criti cal.