Therefore, we aimed to evaluate the differences in clinical manifestations and outcomes, including all-cause mortality, relapse, ESKD, CVA, and ACS, between MPO-ANCA-positive and MPO-ANCA-negative patients with EGPA, as defined by the 2022 ACR/EULAR classification criteria [9], in a Korean cohort. The gene discussed is MPO; the disease is eosinophilic granulomatosis with polyangiitis.