Different types of antiphospholipid antibodies in AIDS: a comparison with syphilis and the antiphospholipid syndrome.

Alloimmune antiphospholipid antibodies react with phospholipids and are an epiphenomenon of an infectious disease. Most autoimmune antiphospholipid antibodies recognise phospholipid-protein complexes or proteins, such as beta2 glycoprotein I or prothrombin and are related to the clinical features of the antiphospholipid syndrome. Lupus anticoagulant, anticardiolipin antibodies, antiprothrombin, and anti-beta2 glycoprotein I antibodies were studied in 61 human immunodeficiency virus (HIV) patients, 55 syphilis patients, and 45 selected patients with antiphospholipid syndrome. Lupus anticoagulant was present in 72% of HIV and 81% of antiphospholipid syndrome patients. None of the syphilis patients had lupus anticoagulant. Anticardiolipin antibodies were found at comparable prevalence in the three groups (HIV 67%, syphilis 67%, antiphospholipid syndrome 84%). HIV had more frequently anti-beta2 glycoprotein I (13%) and antiprothrombin (12%) antibodies than syphilis (0 and 4%, respectively), but significantly less than antiphospholipid syndrome (61 and 40%, respectively). Autoimmune antiphospholipid antibodies in HIV without clinical features of antiphospholipid syndrome might be a reflex of the immunological chaos and/or the constant antigenic virus stimulus.