Clinical manifestations and prognosis of immune-mediated membranous nephropathy concurrent with other glomerulonephritides: A retrospective Chinese cohort analysis.

Objectives: This study aimed to analyze the clinical and prognostic differences in immune-mediated membranous nephropathy (MN) concurrent with other forms of glomerulonephritis.

Materials and methods: A retrospective cohort study at Jinling Hospital from 2015 to 2023 included patients with PLA2R antibody levels ≥ 14RU/mL who underwent renal biopsy. Those with immune-mediated MN and concurrent glomerulonephritides were compared to a control group with isolated MN diagnosed in 2015.

Results: Concurrent glomerulonephritis was found in 5.53% of the MN cohort, including 61 patients with IgA nephropathy (IgAN-MN), 49 with diabetic nephropathy (DN-MN), and 131 with focal segmental glomerulosclerosis (FSGS-MN). Compared to the control group, those with IgAN-MN showed increased severity of glomerular injury yet had a reduced degree of interstitial fibrosis. The DN-MN group exhibited intensified glomerular damage; however, no significant difference was observed in the extent of tubulointerstitial damage. Additionally, the FSGS-MN group displayed more severe damage to both glomerular and tubulointerstitial structures. Both the DN-MN group and the FSGS-MN group exhibited a significantly lower complete remission rate compared to the control group. The renal endpoint event rates were 29.51% for IgAN-MN, 46.94% for DN-MN, and 33.59% for FSGS-MN, which were all significantly higher than the 18.99% rate in the control group.

Conclusion: Patients with MN who test positive for serum Anti-PLA2R antibodies may present with other forms of glomerulonephritis. The prognostic outcomes of MN in the presence of concurrent IgAN, DN, or FSGS are notably poorer than those of isolated MN. Renal biopsy is valuable for definitive diagnosis and prognostic evaluation.