The Coagulation Abnormalities in Systemic Lupus Erythematosus

Abstract

SummaryAn anticoagulant occurring in 4 of 6 patients with SLE has been demonstrated by a sensitive assay utilizing an ammonium sulfate fraction of serum. The anticoagulant functions as an inhibitor of the activation of prothrombin. No species specificity was demonstrable. The inhibitor behaves clinically and chromatographically as an immunoglobulin, although an attempt to demonstrate directly the antibody nature of the inhibitor was not successful.A severe, apparently independent, decrease in the level of prothrombin was observed in the patient with hemorrhagic symptoms. In contrast to the anticoagulant activity, the low prothrombin has persisted during treatment.

The lupus anticoagulant

“…Thus the PTT of a mixture of normal plasma and plasma containing the L A will be the same immediately after mixing as it is after 1 hour of incubation at 37°C (7.32). This result is in contrast to that with anticoagulants directed against a specific coagulation factor (e.g., (23)(24)(25).…”

“…The available data indicate that the L A acts by inhibiting the interaction of formed prothrombin activator complex (Factor Xa, Factor V, and phospholipid) with prothrombin (23)(24)(25)(26). The LA appears to be specifically directed against the platelet phospholipid portion of the prothrombin activator complex (2,27-29).…”

“…Many patients with the LA also have a n associated deficiency of factor I1 (prothrombin) activity (25,26,32,36). T h e cause of factor I1 deficiency in patients with the LA is unknown.…”

Acquired Inhibitors in Nonhemophilic Patients

“…The activity of all clotting factors is normal if the patient's plasma in the test system is diluted to such an extent that the inhibitor does not interfere with the reaction. The only exception is prothrombin which in a number of cases was found to be reduced [19,27,32,53,62,93,99,124,131,135,144,153], For the following reasons it is almost certain that this is a true prothrombin deficiency: In the one-stage assay, the activity of prothrombin remains low if the patient's plasma is appropriately diluted. The deficiency may also be demonstrated by the two-stage technique, by the staphocoagulase assay and by immunolo gical determination of prothrombin (table IV).…”

Lupus Anticoagulant and Anticardiolipin Antibodies in Systemic Lupus erythematosus

“…The administration of corticosteroids may result in the reduction or disappearance of the LA activity [2,47]. A vanishing of the LA has also been reported in a few cases following treatment with plasmaphere sis or immunosuppressive drugs [19], Lubbe et al [48] described a successful outcome of pregnancy in pa tients who had suffered recurrent fetal loss following treatment with high doses of prednisone and low-dose aspirin.…”