MPO and vasculitis: Of the 159 patients with MPO-ANCA–associated vasculitis with GN, MMF was used as a remission-maintenance immunosuppressant in 61 (38%) patients, azathioprine in 53 (33%) patients, low-dose oral prednisone alone in 26 (16%) patients, rituximab in 11 (7%) patients, methotrexate in six (4%) patients, and cyclophosphamide in two (1%) patients (Supplemental Table 1).