[Congenital protein C deficiency and thromboembolic diseases].

Besides its cofactor protein S and antithrombin III, protein C is one of the most important inhibitors of plasma coagulation. In seven members of a family as well as in three further unrelated patients, a congenital protein C deficiency with thromboembolic diseases including a coumarin necrosis was observed in two cases. Deficiency of protein C predisposes to the occurrence of thromboembolism, but the severity of the underlying heterozygotic genetic defect can also vary within the family. Long-term oral anticoagulation with phenprocoumon is the therapy of choice. Genetic counselling should always be carried out.