Two decades outcomes of posttransplant immunoglobulin a nephropathy in live donor renal transplantation

Abstract

Background: The data on long-term outcomes of posttransplant immunoglobulin A nephropathy (IgAN) are confounding and vary with geography and ethnicity worldwide. We aimed to study the long-term graft outcomes of patients with posttransplant IgAN in the northern Indian cohort. Methods: The long-term graft outcomes of 51 live donor renal transplant recipients with biopsy-proven posttransplant IgAN (recurrence/de novo) were analyzed. The risk factors for graft failure in the posttransplant IgA groups were analyzed using the Cox regression analysis. Results: Out of the total of 51 patients who had posttransplant IgAN, 40 patients had a biopsy-proven native kidney IgAN. The mean duration of the clinical presentation of posttransplant IgAN was 62.4 months (5.2 years) posttransplant. Proteinuria at the time of biopsy was 3.03 ± 2.2 g/day, and 41.2% had proteinuria of more than 3 g/day at the time of biopsy. The estimated 1, 5, 10, and 20 years patient survival was 98%, 95.4%, 75.9%, and 25.2%, respectively, and the estimated 1, 5, 10, and 20 years graft survival was 98%, 88.5%, 44.6%, and 11.9%, respectively, in patients who had posttransplant IgA. Many of the traditional risk factors associated with progression in native kidney IgAN, such as the degree of proteinuria, Oxford MEST (mesangial and endocapillary hypercellularity, segmental sclerosis, and interstitial fibrosis/tubular atrophy) scoring, recipient's age, and sex were not predictive of early graft failure among patients with posttransplant IgAN. In our cohort, the only significant graft failure predictor was serum creatinine at 5 years. Chronic antibody-mediated rejection (ABMR) was seen in 21.6% of patients with posttransplant IgAN. Whether this coexistence of chronic ABMR is an incidental finding or posttransplant IgAN predisposes to chronic ABMR requires further investigation. Conclusion: Posttransplant IgAN is associated with poor long-term graft outcomes in live donor renal transplants. Proteinuria and MEST scoring were not predictive of graft failure in living donor posttransplant IgAN.