[Congenital abnormalities related to coagulation and the fibrinolytic system in patients with vein thrombosis of the lower extremities].

Plasma concentrations of antithrombin III (AT III), plasminogen (Plg), and protein C (PC) were assayed in 28 patients with venous thrombosis of lower extremities without distinct underlying disorders. Three abnormalities were found in 5 cases (17.8%) in relation to coagulation and fibrinolytic system (3 with congenital AT III deficiency, one each with dysplasminogenemia and congenital PC deficiency). In the patients with either one of these abnormalities, characteristic features of thrombosis are summarized as follows; 1. early onset of clinical symptoms. 2. high frequency of superficial vein thrombosis. 3. high recurrence rate. 4. high frequency of pulmonary embolism.