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Updated: Oct 7, 2025

Normothermic Ex Vivo Kidney Perfusion for the Preservation of Kidney Grafts prior to Transplantation
Published on: July 15, 2015
Deceased donor kidneys allocated out of sequence by organ procurement organizations
Kristen L King1,2, S Ali Husain1,2, Adler Perotte3
1Division of Nephrology, Department of Medicine, Vagelos College of Physicians & Surgeons, Columbia University, New York, New York, USA.
Abstract:
Deceased donor kidney allocation follows a ranked match-run of potential recipients. Organ procurement organizations (OPOs) are permitted to deviate from the mandated match-run in exceptional circumstances. Using match-run data for all deceased donor kidney transplants (Ktx) in the US between 2015 and 2019, we identified 1544 kidneys transplanted from 933 donors with an OPO-initiated allocation exception. Most OPOs (55/58) used this process at least once, but 3 OPOs performed 64% of the exceptions and just 2 transplant centers received 25% of allocation exception Ktx. At 2 of 3 outlier OPOs these transplants increased 136% and 141% between 2015 and 2019 compared to only a 35% increase in all Ktx. Allocation exception donors had less favorable characteristics (median KDPI 70, 41% with history of hypertension), but only 29% had KDPI ≥ 85% and the majority did not meet the traditional threshold for marginal kidneys. Allocation exception kidneys went to larger centers with higher offer acceptance ratios and to recipients with 2 fewer priority points-equivalent to 2 less years of waiting time. OPO-initiated exceptions for kidney allocation are growing increasingly frequent and more concentrated at a few outlier centers. Increasing pressure to improve organ utilization risks increasing out-of-sequence allocations, potentially exacerbating disparities in access to transplantation.
Insights
Organ procurement organizations (OPOs) are increasingly using allocation exceptions for deceased donor kidney transplants. This practice, concentrated in a few centers, may worsen transplant access disparities.
Area of Science:
- Nephrology
- Transplant Surgery
- Public Health Policy
Background:
- Deceased donor kidney allocation in the US relies on a ranked match-run system.
- Organ procurement organizations (OPOs) can deviate from this system via allocation exceptions.
Purpose of the Study:
- To analyze the frequency, characteristics, and recipients of OPO-initiated kidney allocation exceptions between 2015 and 2019.
- To identify trends and potential disparities associated with these exceptions.
Main Methods:
- Retrospective analysis of deceased donor kidney transplant match-run data from 2015-2019 in the US.
- Identification and characterization of 1544 kidney transplants involving OPO-initiated allocation exceptions.
Main Results:
- OPO-initiated exceptions increased significantly, with 3 OPOs accounting for 64% of cases.
- Exception donors had less favorable characteristics, yet recipients received kidneys with shorter wait times.
- Allocation exceptions were concentrated at larger transplant centers with higher offer acceptance rates.
Conclusions:
- OPO-initiated kidney allocation exceptions are rising and becoming centralized at outlier centers.
- This trend may lead to increased out-of-sequence allocations, potentially widening transplant access disparities.
- Careful monitoring and policy evaluation are needed to ensure equitable organ distribution.
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Kidney Transplant II: Surgical Procedure
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