Coagulation disorders due to circulating anticoagulants: causes, symptoms, diagnosis, treatment

Circulating anticoagulants are usually represented by autoantibodies that neutralize specific clotting factors in vivo (eg, autoantibodies against Factors VIII and V) or inhibit protein-bound phospholipids in vitro. Sometimes a late type of auto-antibody causes bleeding in vivo, binding prothrombin.

[1], [2], [3], [4], [5], [6]

Forms

Isoantibodies to factor VIII develop in 15-30% of patients with severe hemophilia A as a complication of repeated contact with normal molecules of factor VIII as a substitute therapy.

[7], [8], [9], [10], [11]

Anticoagulants that affect the level of factor VIII

Antibodies to factor VIII can sometimes occur in patients who do not have hemophilia, for example, in women after childbirth, as a manifestation of a systemic autoimmune disease, with transient impairment of immune regulation, in elderly patients in the absence of other diseases. In patients with factor VIII anticoagulants, life-threatening bleeding may develop.

Plasma containing antibodies to factor VIII is characterized by an increase in partial thromboplastin time, which is not corrected by the addition of normal plasma or another factor VIII source in a 1: 1 ratio to the plasma of the patient. Testing is performed immediately after mixing and after incubation.

Therapy with cyclophosphamide and glucocorticoids can reduce the production of autoantibodies in patients who do not have hemophilia. In women in the postpartum period, autoantibodies can disappear spontaneously.

[12], [13], [14], [15],

Diagnostics of the coagulation disorders

The presence of circulating anticoagulants should be suspected in patients with severe bleeding, an increase in both partial thromboplasty-new time and prothrombin time, which are not corrected by repeated testing of the mixture of normal plasma and patient plasma in a 1: 1 ratio.

Antiphospholipid antibodies usually contribute to the development of thrombosis. However, in some patients, antibodies bind to the prothrombin-phospholipid complex, inducing hypoprothrombinemia, which can lead to marked bleeding.

[16], [17], [18], [19], [20]

Treatment of the coagulation disorders

Therapy with cyclophosphamide and glucocorticoids can reduce the production of autoantibodies in patients who do not have hemophilia. In women in the postpartum period, autoantibodies can disappear spontaneously.