CD40LG and autoimmune polyendocrinopathy: Antiphospholipid syndrome (APS) is an autoimmune disease that manifests as arterial, venous, or microcirculatory thromboses as well as obstetric complications.1 The diagnosis of APS requires the presence of IgG or IgM anti-β2-glycoprotein-1 or anticardiolipin antibodies by enzyme-linked immunosorbent assay or lupus anticoagulant (LA) assays that must persist for more than 12 weeks.