Platelet and Fibrinogen Consumption in Man

Survival and turnover measurements of platelets and fibrinogen in 35 normal subjects and 104 selected patients defined three types of consumptive processes involving the hemostatic apparatus. The first, characterized by combined platelet and fibrinogen consumption, represents an exaggeration of the physiologic hemostatic response. It occurs in patients with venous thrombosis, tissue trauma, widespread cancer, obstetric complications, and bacteremia. The result of activation of the coagulation system, this process can be modified by heparin. The second, characterized by selective platelet destruction, appears to reflect platelet thrombus formation on abnormal surfaces in the arterial system, including prosthetic devices and arterial thrombosis, thrombotic thrombocytopenic purpura, hemolytic-uremic syndrome, and vasculitis syndromes. This process is reversed by certain inhibitors of platelet function or adrenocortical steroid suppression of vascular inflammation. The third involves selective destruction of fibrinogen and follows the infusion of urokinase. Isolated fibrinogen destruction seems typical of primary fibrinolytic syndromes.