Efficacy of Allocation Decision-Making Based on Preimplantation Biopsy Results

Worldwide, a significant number of kidneys are discarded due, in large part, to results from the preimplantation biopsy. Olivier Aubert, MD, PhD, and colleagues at the Paris Translational Research Center for Organ Transplantation, Paris, France, conducted a study to examine the value of preimplantation biopsies to predict long-term allograft outcome. Results were reported during an oral presentation session at Kidney Week 2019 in a presentation titled Absence of Additional Predictive Ability Value of Preimplantation Biopsies for Long-Term Allograft Outcome.

The development cohort included patients who underwent kidney transplantation from a deceased donor in two French referral centers between 2004 and 2014; the donor organs had preimplantation biopsy results. The study also included two validation cohorts: 1107 deceased donors from Belgium and 1103 discarded kidneys based on biopsy results from the United States.

There were 1629 patients in the development cohort. Preimplantation biopsy findings included interstitial fibrosis and tubular atrophy (IFTA), Banff cv and ah scores, and glomerulosclerosis percentage. Following adjustment for donor, recipient, and transplant characteristics, as well as for preimplantation biopsy findings and baseline immunological parameters, Kidney Donor Risk Index score (hazard ratio [HR], 2.50; 95% confidence interval [CI], 1.38-3.40; P<.001), the presence of circulating donor-specific antibodies on the day of transplantation (HR, 1.76; 95% CI, 1.36-2.28; P<.001), prior kidney transplantation (HR, 1.34; 95% CI, 1.01-1.78; P=.045), and the IFTA score (HR, 1.51; 95% CI, 1.00-2.26; P=.048) were identified as the main independent determinants of long-term allograft loss.

However, there was no additional value in the biopsy results for the prediction of long-term allograft outcome compared with the model with no biopsy results. In the Belgium validation cohort, there were no associations with allograft loss with any of the biopsy results. Kidneys discarded based in histology results in the United States were matched with transplanted kidney in France. The French kidneys with histologic results similar to those of discarded US kidneys did not have worse allograft survival compared with the unmatched transplanted kidneys (P=.156).

In conclusion, the authors said, “Given this result and the fact that preimplantation biopsies increase the cold ischemia time, the current practice of discarding kidneys based on preimplantation biopsy results may not be optimal for allocation decision-making.”

Source: Aubert O, Raynaud M, Divard G, et al. Absence of additional predictive ability value of preimplantation biopsies for long-term allograft outcome. Abstract of an oral presentation at the American Society of Nephrology Kidney Week 2019 (Abstract TH-OR129), November 7, 2019, Washington, DC.