Antiphospholipid Antibody Syndrome

The antiphospholipid antibody syndrome is defined as the presence of arterial or venous thrombosis and pregnancy complications in the setting of antiphospholipid antibodies. When arterial thrombosis occurs, it is most commonly in the brain. These autoantibodies appear to cause clinical symptoms by working in concert with phospholipid-binding proteins, which then bind on endothelial and other cells leading to a proinflammatory or hypercoagulable state. Stroke associated with antiphospholipid antibodies occurs most commonly in young people, and in people with systemic lupus erythematosus, and should be considered as a possible cause in these groups. The recommended treatment is warfarin therapy. Ongoing studies are evaluating the effectiveness of direct thrombin inhibitors and immunotherapies. Adjunctive treatments if thrombosis recurs on warfarin include hydroxychloroquine and statins. Search for vitamin D deficiency in patients with antiphospholipid antibody syndrome is important as vitamin D deficiency is both common and has been associated with an increased frequency of thrombotic events.