In addition, eosinophils activated in EGPA can also participate in EGPA pathogenesis by releasing eosinophil cationic protein (ECP), eosinophil-derived neurotoxin (EDN), eosinophil peroxidase (EPO), and others (Gioffredi et al., 2014; Furuta et al., 2019), which could specifically contribute to the distinct clinical features of EPGA (Table 1). This evidence concerns the gene EPO and eosinophilic granulomatosis with polyangiitis.