ObjectiveWe aimed to validate and modify the renal risk score for antineutrophil cytoplasmic antibody (ANCA)-associated glomerulonephritis (AAGN) in a Chinese cohort with a majority of myeloperoxidase (MPO)-positive patients.MethodsA total of 285 AAGN patients with biopsy-proven in our center were retrospectively included. Patients were randomly assigned to the development set (n=201) and the validation set (n=84). We calculated the renal risk score and analyzed the clinicopathological characteristics and follow-up data. The nomogram was constructed based on the independent prognostic factors identified by the multivariable Cox regression and then compared with the renal risk score.ResultsOver a median follow-up period of 41.3 (20.0-63.8) months, 84 (29.5%) patients reached endstage kidney disease (ESKD). In the development set, hypertension (HR=2.163, 95%CI 1.083-4.322, P=0.029), high serum creatinine (HR=1.002, 95%CI 1.001-1.003, P<0.001), high daily urine protein (HR=1.343, 95%CI 1.148-1.571, P<0.001), high glomerular sclerosis (HR=13.983, 95%CI 3.496-55.923, P<0.001), and interstitial fibrosis>50% (HR=4.179, 95%CI 1.900-9.192, P<0.001) were independent risk factors for ESKD, and these indicators were included in the nomogram. The C-indices of the nomogram model in the development set, validation set, and all-data set were 0.838 (0.785-0.891), 0.794 (0.774- 0.814), and 0.822 (0.775-0.869), respectively, which were higher than those of the renal risk score model, 0.801 (0.748-0.854), 0.746 (0.654-0.838) and 0.783 (0.736-0.830), respectively. And the net reclassification improvement and the integrated discrimination improvement further illustrated the higher predictive ability of the nomogram.ConclusionWe present a nomogram as a practical tool to predict renal outcomes in Chinese patients with an MPO-ANCA glomerulonephritis.
