The clearance of 125I-labelled fibrin from the subcutaneous tissue of limbs with lipodermatosclerosis

The clearance of radioactive fibrin from the subcutaneous tissues has been measured in the rat and in the limbs of normal subjects, patients with varicose veins, and patients with lipodermatosclerosis. The animal experiments showed that the most effective way of producing a subcutaneous deposit of fibrin was by the simultaneous injection of labelled fibrinogen and thrombin. The clearance of these clots was delayed when fibrinolysis was depressed with epsilon-aminocaproic acid. Clearance of subcutaneous fibrin in man was significantly slower in the arms of patients with varicose veins and lipodermatosclerosis. Similarly clearance in the legs of patients with lipodermatosclerosis was significantly slower than that of the normal subjects and those with uncomplicated varicose veins. The clearance of fibrin from the legs of patients with lipodermatosclerosis was significantly slower than the clearance from their arms but there was no difference between arm and leg clearance in the normal subjects and those with uncomplicated varicose veins. The patients with lipodermatosclerosis had a significantly longer dilute blood clot lysis time. The inability to clear subcutaneous fibrin may be an aetological factor of lipodermatosclerosis.