In WG, genetic polymorphism of the receptor for the Fc fragment of immunoglobulins G (FcγR) may decrease Staphylococcus aureus clearance, thus promoting chronic carriage and resulting in preferential binding of FcγR to a subset of IgG-ANCA isotypes characterised by marked immunogenicity [7]. Here, FCGR2A is linked to granulomatosis with polyangiitis.