Patients with antiphospholipid syndrome (APS) may not have SLE or present with any definable disease. By contrast, APS does occur in relation to SLE, rheumatic, or autoimmune disorders in other patients. Thrombotic events occur in up to 30% of patients with APS, with the most common events resulting in deep vein thrombosis (DVT), pulmonary embolism (PE), and cerebral arterial thrombosis. Stroke may also occur in younger individuals. One of the most serious APS complications occurs during pregnancy, resulting in recurrent spontaneous miscarriage, fetal death, or fetal developmental delay.
