Coagulation defect of congenital tyrosinaemia.

Three infants with hereditary tyrosinaemia had a severe coagulation defect due to a combination of deficient hepatic synthesis of clotting factors and a consumption coagulopathy. In all three plasma failed to clot normally with the venom of Bothrops atrox (Reptilase) and we attribute this to a defect of fibrinogen (dysfibrinogenaemia). Treatment was unsuccessful, and all died.