Antiphospholipid syndrome: an overview.

Antiphospholipid antibodies are a heterogeneous group of autoantibodies that are detected by immunoassays and functional coagulation tests. The antigenic targets are negatively charged phospholipids and serum phospholipid-binding proteins. The latter antibodies are frequently associated with thrombosis, fetal loss and other clinical manifestations of the antiphospholipid syndrome. These antibodies are felt to be etiologically important in the syndrome, although the precise pathogenic mechanisms are still being determined. Proposed mechanisms include antibody-mediated interference with coagulation homeostasis, activation of platelets and endothelial cells and a T-cell immune response to serum phospholipid-binding proteins. The mainstay of therapy is anticoagulation, whereas immunosuppression is ineffective.