ABSTRACT

Antiphospholipid syndrome (APS) is a systemic autoimmune disease which occurs secondary to antiphospholipid antibodies (aPL) and results in vascular thromboses and/or pregnancy morbidity. The most commonly used tests to detect aPL are lupus-anticoagulant (LA) assay, anticardiolipin ELISA, and anti-b2-glycoprotein-I ELISA. Although these aPL tests are important for diagnosis, physicians should keep in mind that the presence of aPL is only one of many thrombosis risk factors and the risk multiplies with additional factors. In persistently aPL-positive patients without thrombosis, the elimination of reversible thrombosis risk factors and aggressive prophylaxis during high-risk periods are crucial. In this group of patients, the effectiveness of low dose aspirin (LDA) is not supported by prospective controlled studies, however, LDA can be considered in ''high cardiovascular (CVD) risk'' aPL-positive patients with other CVD risk factors such as hypertension or smoking. In persistently aPL-positive patients with thrombosis, the acute treatment is heparin followed by the long-term warfarin to prevent recurrence (target INR: 2.5-3); in patients with single events, the effectiveness of high-intensity anticoagulation (INR: 3-4) is not supported by prospective controlled studies. During the pregnancies of aPL-positive patients, LDA and prophylactic dose heparin combination is used for APS patients with history of pregnancy morbidity only, and LDA and therapeutic dose heparin combination is used for APS patients with history of thrombosis regardless of pregnancy history. Catastrophic APS patients usually receive a combination of ''anticoagulation, corticosteroids, and intravenous immunoglobulin or plasma exchange''. The role immunomodulation in aPL-positive patients has been studied by experimental APS models and pilot clinical studies; controlled clinical trials testing the effectivenss of hydroxychloroquine, statins, or biologic agents can be considered in the near future.