The Antiphospholipid syndrome characterized by venous or arterial thrombosis, pregnancy loss, thrombocytopenia, neurologic disease. APS is associated with persistently positive tests for anticardiolipin or lupus anticoagulant. The lupus anticoagulant is assessed by Partial Thromboplastin Time (PTT) and modified Russell Viper Venom Time (RVVT). Anticardiolipin antibodies bind to immobilized cardiolipin in an enzyme linked immuonosorbent assay (ELISA). Treatment of APS remains empirical and directed to coagulation and immune mechanisms.