Reassessment of renal prognosis in patients with membranoproliferative glomerulonephritis according to the new pathologic classification

Membranoproliferative glomerulonephritis (MPGN) is a heterogeneous disease characterized by a morphological injury pattern that can be seen under various disease conditions that share common pathogenic mechanisms. In this study, we analyzed clinical features, pathological findings, long-term kidney outcomes according to the new pathohistological classification of MPGN. Methods. This retrospective study included 20 CKD patients with biopsy-proven MPGN that had been diagnosed between 2011 and 2019. We reclassified the patterns of MPGN as immune-complexes mediated (ICM) and complement-mediated (CM) according to the new classification. Results. The level of daily proteinuria was lower in the ICM MPGN than the CM MPGN group but was not statistically significant at the end of the study. Histopathologically, the difference in C3 staining was found between the patients with ICM and CM MPGN. At the end of the follow-up period, no patients developed end-stage renal disease, and no death occurred in response to treatment in the ICM MPGN group. In the CM MPGN group, 2 patients evolved to end-stage renal disease and 1 of them had renal transplantation. Conclusion. Larger sample size and longer follow-up may change the relationship between histological factors, treatment strategies, and kidney outcomes. We believe that the use of the new diagnostic approach that applies to the ICM MPGN and CM MPGN will help nephrologists to improve treatment options and renal outcomes for patients with MPGN.