The disease duration refers to the time from diagnosis to first RTX treatment. BVAS and organ involvement was evaluated before CYC induction and before the first RTX treatment. Eosinophil counts and IgE concentration were measured before induction therapy with CYC (n = 7), MTX (n = 1), or AZA (n = 1). Abbreviations for organ involvement: ear nose throat (ENT), cardiac (C), kidney (K), lung (L), peripheral nervous system (PNS), central nervous system (CNS), and skin (S). FFS, five-factor score; IF, immunofluorescence; ELISA, enzyme-linked immunosorbent assay; BVAS, Birmingham Vasculitis Activity Score. Arrows, organ involvement at the time of RTX treatment compared with initial manifestation before standard therapy: ↑, worsening of organ involvement; ↓, improvement of organ involvement; ↔ stable organ involvement.