Impact of Deceased Donor Kidney Procurement Biopsy Technique on Histologic Accuracy

Abstract

Introduction: The factors that influence deceased donor kidney procurement biopsy reliability are not well established. We examined the impact of biopsy technique and pathologist training on procurement biopsy accuracy.

Methods: We retrospectively identified all deceased donor kidney-only transplants at our center from 2006 to 2016 with both procurement and reperfusion biopsies performed and information available on procurement biopsy technique and pathologist (n = 392). Biopsies were scored using a previously validated system, classifying "suboptimal" histology as the presence of at least 1 of the following: glomerulosclerosis ≥11%, moderate/severe interstitial fibrosis/tubular atrophy, or moderate/severe vascular disease. We calculated relative risk ratios (RRR) to determine the influence of technique (core vs. wedge) and pathologist (renal vs. nonrenal) on concordance between procurement and reperfusion biopsy histologic classification.

Results: A total of 171 (44%) procurement biopsies used wedge technique, and 221 (56%) used core technique. Results of only 36 biopsies (9%) were interpreted by renal pathologists. Correlation between procurement and reperfusion glomerulosclerosis was poor for both wedge (r ² = 0.11) and core (r ² = 0.14) biopsies. Overall, 34% of kidneys had discordant classification on procurement versus reperfusion biopsy. Neither biopsy technique nor pathologist training was associated with concordance between procurement and reperfusion histology, but a larger number of sampled glomeruli was associated with a higher likelihood of concordance (adjusted RRR = 1.12 per 10 glomeruli, 95% confidence interval = 1.04-1.22).

Conclusions: Biopsy technique and pathologist training were not associated with procurement biopsy histologic accuracy in this retrospective study. Prospective trials are needed to determine how to optimize procurement biopsy practices.

Keywords: deceased donor kidney transplant; epidemiology; kidney procurement biopsy; kidney transplant outcomes; organ quality; organ utilization.

Graphical abstract

Figure 1

Flow diagram of study cohort.

Figure 2

Histogram of number of glomeruli sampled, by procurement biopsy technique. Wedge biopsies were associated with a higher mean number of glomeruli sampled compared to core biopsies (56 ± 35 vs. 44 ± 25, P < 0.001).

Figure 3

Percent glomerulosclerosis on procurement biopsy versus reperfusion biopsy, by biopsy technique. Correlation between procurement and reperfusion glomerulosclerosis was low regardless of whether wedge (r² = 0.11) or core (r² = 0.14) technique was used for the procurement biopsy. The black line is a reference for concordance.