[Antiphospholipid syndrome and the pneumologist].

The antiphospholipid syndrome (APS) is usually defined by the association of a clinical manifestation (venous or arterial thrombosis or miscarriage) with the presence of antiphospholipid antibodies (lupus anticoagulant and/or anticardiolipin antibodies). It frequently occurs in the course of systemic lupus erythematosus but is also encountered as a "primary" disease. APS is responsible for diverse respiratory manifestations. Pulmonary embolism is common. The site of the causal venous thrombosis is frequently unusual. Pulmonary hypertension may be a consequence of repeated embolism or may belong to the primary idiopathic variety. Pulmonary manifestations may also result from left-sided heart failure due to mitral or aortic valve abnormalities, myocardial infarction or a specific myocardiopathy. APS is probably involved in the occurrence of some cases of adult respiratory distress syndrome. Long term secondary prevention of recurrent thrombosis is a central point in the management of APS.