CD40LG and autoimmune polyendocrinopathy: In addition to the conventional markers for classification of APS, lupus anticoagulant (LA), anticardiolipin antibodies (aCL), and anti-β2glycoprotein I (aβ2GPI) antibodies with IgG and/or IgM isotypes and according to the last international consensus guidelines on antiphospholipid antibodies, testing for IgA isotype is recommended for both aCL and aβ2GPI when results of conventional markers are negative and APS is still suspected [4].