Hematin: Unique Effects on Hemostasis

Hematin is clincally useful in the treatment of acute intermittent porphyria. Recently, hematin-induced coagulopathy has been reported. and a patient we treated bled during hematin therapy. On 3 separate occasions. infusions of hematin (4 mg/kg) induced thrombocytopenia, prolongation of the prothrombin time, partial thromboplastin time. Reptilase time and apparent decreases in fibrinogen and increases in fibrin (ogen) degradation products (FDP). However, fibrinogen assayed by heat precipitation was unchanged. the protamine paracoagulation test was negative. there was no red blood cell fragmentation, and plasminogen and antithrombin Ill remained normal. excluding the presence of disseminated intravascular coagulation. Furthermore, premedication with heparin, 5000 U i.v.,