Hereditary protein C deficiency--the first symptomatic family in Singapore.

Protein C is an important physiological inhibitor of coagulation. A deficiency of this protein is a recognised cause of recurrent venous thromboembolism. The assay for protein C was not locally available until recently. Our investigation of a young Malay woman who had sustained two previous pulmonary emboli led us to identify the first family in Singapore with this familial disorder. The definitive diagnosis of symptomatic protein C deficiency justifies longterm anticoagulant therapy in two members of this family. We now systematically screen all young adults who present with the first episode of deep venous thrombosis or pulmonary embolism irrespective of whether the event is spontaneous or seemingly precipitated.