Evaluation of Long-term Outcomes and its Related Factors in Patients with Immune-complex Mediated Glomerulonephritis: A 20-Year Historical Cohort Study in Iran.

Abstract

Introduction: Immune-complex mediated glomerulonephritis (IC-GN) has a poor prognosis and commonly leads to kidney failure This study reports 20-year experience with the long-term outcomes of 222 Iranian IC-GN patients.

Methods: This single-center historical cohort study was conducted on patients who underwent kidney biopsies from 1998 to 2018 in Hasheminejad Kidney Center (HKC). Initial demographic, clinical, laboratory, and pathology data were extracted from the glomerulonephritis registry of HKC. Follow-up data was obtained by reviewing hospital and outpatient files, as well as phone calls. The primary outcomes were end-stage kidney disease (ESKD) and death, and the secondary outcomes were complete remission, partial remission, and stable chronic kidney disease.

Results: A total of 222 patients, (141 (63.5%) males, 81 (36.5%) females, mean age: 37.76 ± 15.71 years), were diagnosed with IC-GN. The most common causes were IgA nephropathy and lupus nephritis. Among all, 60.2% progressed to ESKD, 15.5% died, 13.1% achieved complete, and 18.5% achieved partial remission. The overall one-, three-, five-, and ten-years kidney survival rates were 52%, 42%, 38%, and 27%, respectively, with a significant difference between the IC-GN subtypes (P < .001). The highest kidney survival rate was found in lupus nephritis. Significant independent predictors of ESKD were the percentage of interstitial fibrosis and tubular atrophy (adjusted hazard ratio (aHR) = 1.022 [95% confidence interval (CI) = 1.012-1.033]), percentage of active crescents (aHR = 4.002 [95% CI = 2.066-7.752]), and initial serum creatinine level (aHR = 1.073 [95% CI = 1.035-1.112]) (P < .001 for all).

Conclusion: There was a significant difference between the long-term survival of IC-GN types. Histopathologic features, and higher initial serum creatinine levels, were important predictors of poor outcome.