Evaluation of the Modified Oxford Score in Recurrent IgA Nephropathy in North American Kidney Transplant Recipients: The Banff Recurrent Glomerulonephritis Working Group Report

Abstract

Background. The modified Oxford classification mesangial and endocapillary hypercellularity, segmental sclerosis, interstitial fibrosis/tubular atrophy, and the presence of crescents (MEST-C) of immunoglobulin A nephropathy (IgAN) was recently shown to be a predictor of graft failure in Asians with recurrent IgAN. We aimed to validate these findings in a cohort from North American centers participating in the Banff Recurrent Glomerulopathies Working Group. Methods. We examined 171 transplant recipients with end-stage kidney disease because of IgAN; 100 of them with biopsy-proven recurrent IgAN (57 of them had complete MEST-C scores) and 71 with no recurrence. Results. IgAN recurrence, which was associated with younger age at transplantation (P = 0.012), strongly increased the risk of death-censored graft failure (adjusted hazard ratio, 5.10 [95% confidence interval (CI), 2.26-11.51]; P < 0.001). Higher MEST-C score sum was associated with death-censored graft failure (adjusted hazard ratio, 8.57 [95% CI, 1.23-59.85; P = 0.03] and 61.32 [95% CI, 4.82-779.89; P = 0.002] for score sums 2–3 and 4–5 versus 0, respectively), and so were the single components endocapillary hypercellularity, interstitial fibrosis/tubular atrophy, and crescents (P < 0.05 each). Overall, most of the pooled adjusted hazard ratio estimates associated with each MEST-C component were consistent with those from the Asian cohort (heterogeneity I2 close to 0%, and P > 0.05). Conclusions. Our findings may validate the prognostic usefulness of the Oxford classification for recurrent IgAN and support the inclusion of the MEST-C score in allograft biopsies diagnostic reports.

Transplant nephropathology: Wherefrom, wherein, and whereto

“…67 The interdisciplinary collaboration in Banff has also been enhanced recently with the recent publication about recurrent IgA nephropathy in the transplanted kidney. 68 It is impressive to see Banff inspiring other classification efforts even as KDIGO 55 inspires Banff. That augers well for human cooperation in our field even as we face AI challenges!…”

Post-Transplant Glomerulonephritis: Challenges and Solutions

“… 12 Other previous studies showed that a higher MEST-C score and a lower estimated glomerular filtration rate at the time of biopsy were associated with poor prognosis in patients with IgAN recurrence. 13 Some biomarkers for the prediction of post-transplant IgAN recurrence have been studied, such as IgA and IgA-complexes (IgA-IgG and IgA-soluble CD89), galactose-deficient IgA1 (Gd-IgA1), and anti-Gd-IgA1 autoantibodies, although its clinical application is not entirely known. 14 Graft dysfunction related to recurrence is rare before three years of follow-up.…”

“…17 Sodium-glucose cotransporter-2 (SGLT-2) inhibitors are indicated for native IgAN with proteinuria or impaired renal function, and their use can be considered in cases of post-transplant recurrence. 13 Several glucocorticoid regimens were proposed in clinical for patients presenting proteinuria higher than 0.75–1 g/day despite optimized supportive care. 10 However, the clinical benefit of glucocorticoids in IgAN has not been established.…”