[Antiphospholipid syndrome].

Antiphospholipid syndrome (APS) is characterized by recurrent arterial or venous thromboembolism or pregnancy loss in association with antibodies directed against anionic phospholipids or plasma proteins bound to anionic phospholipids. A common cause of the huge variety of clinical manifestations is vaso-occlusive disease and not vasculitis in venous or arterial blood vessels of different sizes and sites (i.e. deep vein thrombosis, pulmonary embolism, cerebrovascular disease). In accordance with this, fetal abortion, typically beyond the tenth week of gestation, is also caused by infarctions of blood vessels in the placenta. Establishing the correct diagnosis of APS is not easy. To estimate the risk of thrombotic complications is challenging, as well as the questions of, which, how long and in what strength anticoagulation is recommended. This paper should enable the reader to apply international consensus classification criteria correctly, to interpret the different laboratory tests for anti-phospholipid antibodies and to gain an awareness of the different forms of anticoagulation in order to stratify therapeutic decisions.