Vasculitis in antiphospholipid syndrome

The major manifestations of antiphospholipid syndrome (APS) are caused by thrombosis within the venous or arterial vasculature, whereas the vascular lesions in systemic vasculitis result from an inflammatory infiltrate in the vessel wall. There is an association between vascular thrombosis and inflammation, however, as vasculitis can occur in APS and thromboembolic complications are seen in systemic vasculitis. Although differentiating between vasculitis and antiphospholipid-associated thrombosis can be difficult, it may be crucial to do so given the different therapeutic implications for immunosuppression or anticoagulation. This article explores the relationship between thrombosis and inflammation as it relates to APS and systemic vasculitis.