The overlap is due to the combination of peripheral eosinophilia (≥ 1 × 109/mcl) and necrotizing pulmonary granulomas associated with an eosinophilic infiltration (which favored EGPA), elevated serum PR3-ANCA levels and ENT involvement with nasal obstruction and saddle nose, which are much more commonly seen in patients with GPA. Here, PRTN3 is linked to eosinophilic granulomatosis with polyangiitis.