Frequency of Kidneys Allocated Out of Sequence

Allocation of deceased donor kidneys follows a ranked match-run list of potential recipients. The frequency of deviation by organ procurement organizations (OPOs) from the mandated match-run in exceptional circumstances is unknown.

Kristen L. King and colleagues conducted an analysis to examine the frequency of exceptions to the standard allocation policy. Results of the analysis were reported during a virtual poster session at ASN Kidney Week 2021 in a poster titled Increasing Frequency of Kidneys Allocated Out of Sequence by Organ Procurement Organizations.

The researchers utilized Scientific Registry of Transplant Recipients data on all deceased donor kidney transplants in the United States from 2015 to 2019 to identify cases where an OPO-initiated allocation exception occurred (operational-OPO, Donor Medical Urgency, or Expedited Placement). The analysis was designed to examine the frequency of deceased donor kidney transplants from exceptions over time as well as the characteristics of donors with kidneys placed out-of-sequence.

During the study period, 981 kidneys from 673 donors were transplanted via OPO-initiated allocation exception. During that same time period, transplants with allocation exceptions (median kidney donor profile index [KDPI] 67, age 47 years) nearly doubled, from 153 kidneys in 2015 (1.5% of all deceased donor kidney transplants) to 291 in 2019 (2.1%).

The process of allocation exception was used at least once by 52 of 58 OPOs (median ≤1 per year). However, two outlier OPOs accounted for 54% all the exceptions over 5 years (426 [43%[ and 110 [11%]). Only 56% of any transplant centers received any allocation-exception deceased donor kidney transplants, with two centers receiving 26% (129 [13%] and 132 [13%]).

Characteristics of donor kidneys placed via allocation exception were less favorable, but only 25% had KDPI ≥85%. Allocation exemption kidneys went to recipients with two fewer priority points (median score: 4.3 vs 6.3 in-sequence), the equivalent of 2 fewer years of waiting time.

In conclusion, the researchers said, “Two OPOs and a few kidney transplant centers are driving an increase in OPO-initiated exceptions in kidney allocation. Although kidneys placed out-of-sequence were lower quality, the majority did not meet the traditional threshold for marginal kidneys. Without monitoring, increasing pressure to improve organ utilization risks increasing out-of-sequence allocation potentially exacerbating disparities in access to transplantation.”

Source: King KL, Husain SA, Mohan S. Increasing frequency of  kidneys allocated out of sequence by organ procurement organizations. Abstract of a poster presented at the American Society of Nephrology virtual Kidney Week 2021 (Abstract PO2104), November 2021.