Male sex − n (%)MPA vasculitis − n (%)RLV − n (%)PR3-ANCA positive − n (%)MPO-ANCA positive − n (%)Serum creatinine 251-400 μmol/L − n (%)Serum creatinine 401-600 μmol/L − n (%)Serum creatinine >600 μmol/L − n (%)Brix score ≥7 − n (%)Berden classification: crescentic class − n (%)Berden classification: mixed class − n (%). This evidence concerns the gene PRTN3 and microscopic polyangiitis.