Procurement biopsies in the evaluation of deceased donor kidneys

Abstract

Background and objectives Biopsies taken at deceased donor kidney procurement continue to be cited as a leading reason for discard; however, the reproducibility and prognostic capability of these biopsies are controversial. Design, setting, participants, & measurements We compiled a retrospective, single-institution, continuous cohort of deceased donor kidney transplants performed from 2006 to 2009. Procurement biopsy information—percentage of glomerulosclerosis, interstitial fibrosis/tubular atrophy, and vascular disease—was obtained from the national transplant database. Using univariable, multivariable, and time-to-event analyses for death-censored graft survival, we compared procurement frozen section biopsy reports with reperfusion paraffin-embedded biopsies read by trained kidney pathologists (n=270). We also examined agreement for sequential procurement biopsies performed on the same kidney (n=116 kidneys). Results For kidneys on which more than one procurement biopsy was performed (n=116), category agreement was found in only 64% of cases (k=0.14). For all kidneys (n=270), correlation between procurement and reperfusion biopsies was poor: overall, biopsies were classified into the same category (optimal versus suboptimal) in only 64% of cases (k=0.25). This discrepancy was most pronounced when categorizing percentage of glomerulosclerosis, which had 63% agreement (k=0.15). Interstitial fibrosis/tubular atrophy and vascular disease had agreement rates of 82%(k=0.13)and80%(k=0.15), respectively. Ninety-eight (36%) recipients died, and 56 (21%) allografts failed by the end of follow-up. Reperfusion biopsies were more prognostic than procurement biopsies (hazard ratio for graft failure, 2.02; 95% confidence interval, 1.09 to 3.74 versus hazard ratio for graft failure, 1.30; 95% confidence interval, 0.61 to 2.76), with procurement biopsies not significantly associated with graft failure. Conclusions We found that procurement biopsies are poorly reproducible, do not correlate well with paraffin-embedded reperfusion biopsies, and are not significantly associated with transplant outcomes.