The presence of antibodies directed against phospholipids (ANTIBODIES, ANTIPHOSPHOLIPID). The condition is associated with a variety of diseases, notably systemic lupus erythematosus and other connective tissue diseases, thrombopenia, and arterial or venous thromboses. In pregnancy it can cause abortion. Of the phospholipids, the cardiolipins show markedly elevated levels of anticardiolipin antibodies (ANTIBODIES, ANTICARDIOLIPIN). Present also are high levels of lupus anticoagulant (LUPUS COAGULATION INHIBITOR).

Synonyms: Antiphospholipid Syndrome, Antiphospholipid Antibody Syndrome, Anti-Phospholipid Syndrome, Antibody Syndrome, Antiphospholipid, Antibody Syndrome, Anti-Phospholipid, Hughes Syndrome, Anti Phospholipid Syndrome, Antiphospholipid Antibody Syndromes, Syndrome, Anti-Phospholipid Antibody, Syndrome, Antiphospholipid Antibody, Syndrome, Antiphospholipid, Anti Phospholipid Antibody Syndrome, Syndrome, Anti-Phospholipid, Anti-Phospholipid Antibody Syndrome, Syndrome, Hughes