Life-threatening bleeding due to an acquired inhibitor to factor XII-XI successfully treated with 'activated' prothrombin complex concentrate (FEIBA)

Abstract

Five instances of inhibitor to factor XII-XI have been reported so far. These have arisen in two women suffering from systemic lupus erythematosus and in three patients with Waldenstrom macroglobulinaemia. None of these patients had a bleeding tendency. The authors believe that it is of interest to report a 45-year-old female with an 18 years history of a bleeding tendency, who developed life-threatening vaginal bleeding following total hysterectomy for rupture of an ovarian cyst. Coagulation studies revealed a prolonged whole blood clotting time of 19 min and an activated partial thromboplastin time of 199 s (control 40 s). Further experiments showed that the patient's plasma at the dilution of 1:32 inhibited a contact product preparation thus indicating an inhibitor to factor XII-XI. The patient was treated with a variety of blood products without success but the administration of FEIBA 60 units/kg/d for 4 d was followed by the arrest of bleeding. The patient recovered completely. She had no evidence of an associated systemic disease but the inhibitor is still present in the plasma.