Background. The Banff classification scheme provides a framework for interpreting transplant kidney biopsies and has undergone various updates in the past 2 decades especially related to antibody-mediated rejection. The clinical significance of early glomerulitis seen within 4 mo on protocol biopsies has received limited attention. We hypothesized that early glomerulitis seen on protocol biopsies will lead to significant adverse outcomes as assessed by histopathology and allograft outcome. Methods. A single-center retrospective study of a cohort of patients who underwent protocol biopsies within 4 mo after transplantation with timely follow-up protocol biopsies were assessed. Patients with recurrent glomerulonephritis were excluded. Results. We calculated glomerulitis (g) scores for 2212 biopsy specimens and identified 186 patients with glomerulitis (g > 0) and 2026 patients without glomerulitis (g = 0). The progression to chronic transplant glomerulopathy at 1 and 2 y was higher in patients with g > 0 as compared with g = 0 (year 1, 10.7% versus 2.3% [P < 0.001]‚ respectively; year 2, 17.2% versus 4.3% [P < 0.001], respectively) with no difference in other chronic lesions. The death-censored graft failure rate was higher in patients with g > 0 as compared with g = 0 (hazard ratio, 1.68 [95% CI, 1.07-2.65]; P = 0.02). We did not find any difference in outcomes in glomerulitis group based on donor-specific antibody. Conclusion. Our findings suggest that early glomerulitis (seen within 4 mo after transplantation) may lead to clinically significant long-term changes and thus could be a target for early intervention therapies.
Correlation of Chronic Histologic Changes on Preimplantation Frozen Section Biopsy With Transplant Outcomes After Deceased Donor Kidney Transplantation
Context.— It is unclear if preimplantation frozen section biopsy correlates with outcomes after deceased donor kidney transplantation. Objective.— To assess if chronic histologic changes on the preimplant frozen section correlates with graft loss and estimated glomerular filtration rate independently of kidney donor profile index (KDPI). Design.— Seven hundred three preimplantation biopsies were reviewed and a Banff sum score was calculated using glomerular sclerosis, interstitial fibrosis, vascular intimal thickening, and arteriolar hyalinosis. The posttransplant outcomes were compared for preimplantation biopsy Banff sum 0-1, 2-3, and 4-9. The cohort was also stratified by KDPI 85 or less versus more than 85. Results.— For the entire biopsy cohort, graft survival, estimated glomerular filtration rate at 1 year, and chronic changes on a 1-year posttransplant biopsy were superior in the group with preimplantation Banff sum 0-1. After stratifying by KDPI, the Banff sum no longer correlated with graft survival. In a univariate mode, using the Banff sum score as a continuous variable, a higher Banff sum score was significantly associated with graft failure (P = .03); however, after adjusting the KDPI, the Banff sum score no longer correlated with graft failure (P = .45). The 1-year estimated glomerular filtration rate and 1-year biopsy changes were superior in the group with Banff sum 0-1 only in the cohort with KDPI 85 or less. Conclusions.— In donor kidneys used for transplant, preimplantation biopsy chronic changes correlate with estimated glomerular filtration rate and biopsy findings at 1 year, but biopsies with mostly mild chronicity and Banff sum scores less than or equal to 5 did not impact graft survival beyond KDPI.