Antiphospholipid Syndrome

Antiphospholipid antibodies (aPL) represent a broad family of antibodies mainly directed to proteins associated with phospholipids, mainly beta 2 glycoprotein 1. The antiphospholipid antibody syndrome (APS) is characterized by the association of aPL, i.e. Lupus Anticoagulant and/or medium or high titers of IgG or IgM anticardiopin antibodies, with either thrombosis affecting veins, arteries or microvasculature and/or obstetrical events. APS may be isolated, then defined as primary, or associated with systemic lupus erythematosus (SLE). The two techniques used for the detection of aPL in daily practice are the enzyme-linked immunosorbent assay (ELISA) for anticardiolipin antibodies and the coagulation-based assay for lupus anticoagulant. Secondary prevention of thrombosis within APS is based on long term anticoagulation targeting an INR (International Normalised Ratio) between 2 and 3 or between 3 and 4 for the more severe forms of the disease. A lifetime treatement is required in the more severe form of APS. In the absence of associated SLE, steroids are of little benefit, except in the peculiar setting of the "Catastrophic APS" characterized by the simultaneous occurrence of a multi-organ failure due to a widespread thrombotic microangiopathy.