ABNORMAL PROTHROMBIN CROSSED-IMMUNOELECTROPHORESIS IN PATIENTS WITH LUPUS INHIBITORS

  • 1 January 1984
    • journal article
    • research article
    • Vol. 64  (4) , 807-816
Abstract
Prothrombin deficiency has been known to occur in association with lupus inhibitors for over 25 yr. Patients [21] with lupus inhibitors were studied and 4 of 5 with prothrombin deficiency and 6 of 16 with quantitatively normal prothrombin had abnormal prothrombin crossed-immunoelectrophoresis (CIEP) characterized by material moving slower in the first dimension of electrophoresis than normal prothrombin. In 2 patients with prothrombin deficiency, all prothrombin measured by quantitative assay and all slow-moving material on CIEP were removed by treatment with staphylococcal protein A (SPA). These patients had free antibody, which bound to normal plasma prothrombin, forming larger amounts of slow-moving material on CIEP. A 3rd patient with prothrombin deficiency had only partial removal of prothrombin after SPA treatment. Two patients with quantitatively normal prothrombin had all slow-moving material on CIEP and about one fourth of the prothrombin by quantitative assay removed by SPA treatment. There was no correlation among the strength of the inhibitor, the presence of a cofactor effect, and the prothrombin abnormality. Heterogeneous antiprothrombin antibodies, with or without prothrombin deficiency, are present in the majority of patients with lupus inhibitors.