Dear Editor, eosinophilic granulomatosis with polyangiitis (EGPA) is histologically defined by eosinophil-rich, necrotizing granulomatous inflammation primarily involving the respiratory tract along with necrotizing vasculitis (NV) of small-to medium-sized arteries [1]. EGPA encompasses two distinct phenotypes: one is characterized by antineutrophil cytoplasmic antibody (ANCA) positivity and the predominance of vasculitis and is thus closer to other forms of ANCA-associated vasculitis (AAV); the other involves prominent eosinophilia and thus is more similar to hypereosinophilic syndrome (HES) [2].
