PRTN3 and chronic kidney disease: A severe, chronic decrease in kidney function in terms of CKD stage G4-5 occurred in 5/52 (9.6%) patients with one case in the PR3-ANCA subgroup (1/27, 3.7%) and four cases in the MPO-ANCA subgroup (4/25, 16.0%), again displaying no significant subgroup difference (p = 0.1709, Table 1).