The Nature and Action of Circulating Anticoagulants

Abstract

Three patients with circulating anticoagulants are reported, 2 being hemophilics and the 3rd a previously normal individual. The anticoagulants in all 3 cases inhibited the formation of blood thromboplastin by preventing a reaction between antihemophilic globulin and serum. They were all heat stable, present in the gamma and beta globulin fractions of serum and gave positive precipitin tests to anti-hemophilic globulin. It appears therefore that the circulating anticoagulants in hemo-philic and in non-hemophilic patients are at least of a closely allied if not identical nature. It was found that the platelets in all 3 cases were normal in respect of thromboplastin generation and that the incubation of plasma containing the circulating anticoagulant with normal plasma may result in a fall of the clotting time of the mixture to normal without affecting the titre of the anticoagulant The administration of ACTH or cortisone did not prevent hemorrhagic manifestations nor alter the titer of the circulating anticoagulants in the 2 cases in which these 2 hormones were used.