Among all 97 patients with MPO-ANCA GN, 59% (57/97) of patients had no or few deposits in their glomeruli from renal biopsy, which were classified as the “pauci-immune” (PI) group, while the other 41% (40/97) of cases were classified as the “immune complex” (IC) group. Here, MPO is linked to ganglioneuroma.