ABSTRACT
The antiphospholipid syndrome (APS) is a multisystem disease with predominant clinical features of venous and arterial thrombosis, recurrent pregnancy loss, chorea, cardiac valvular abnormalities, thrombocytopenia, and the presence of antiphospholipid antibodies (aPL). There are several methods in clinical use for detecting aPL antibodies. Prolongation of in vitro phospholipid-dependent clotting tests detects lupus anticoagulant antibodies and a solid phase immunoassay employing cardiolipin as the coated antigen detects anticardiolipin antibodies (aCL). By modifying the chemical structure and synthesising analogues of the parent molecule, the binding characteristics of aPL in syphilis were studied. J. Font et al. have reported an increased expression of Tissue factor in monocytes incubated with plasma from autoimmune patients with aPL and thrombosis. The phenothiazine group of drugs, in particular chlorpromazine, is the most common cause of drug-induced aPL. S. Loizou et al. found that sera from aCL positive autoimmune patients had a significant statistical association with vascular thrombosis and thrombocytopenia.
