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Updated: Feb 14, 2026

The Mouse Isolated Perfused Kidney Technique
Published on: November 17, 2016
Unintended Consequences in Use of Increased Risk Donor Kidneys in the New Kidney Allocation Era
A A Rahnemai-Azar1, J D Perkins1, N Leca2
1Division of Transplant Surgery, Department of Surgery, University of Washington Medical Center, Seattle, Washington.
Background:
The new kidney allocation system (KAS) intends to allocate the top 20% of kidneys to younger recipients with longer life expectancy. We hypothesized that the new KAS would lead to greater allocation of Public Health Service (PHS) increased-risk donor organs to younger recipients.
Methods:
Analyses of the Organ Procurement and Transplantation Network data of patients who underwent primary deceased kidney transplantation were performed in pre- and post-KAS periods.
Results:
The allocation of PHS increased-risk kidney allografts in various age groups changed significantly after implementation of the new KAS, with an increased proportion of younger individuals receiving increased-risk kidneys (7% vs 10% in age group 20-29 y and 13% vs 18% in age group 30-39 y before and after KAS, respectively; P < .0001). This trend was reversed in recipients 50-59 years old, with 31% in the pre-KAS period compared with 26% after KAS (P < .0001).
Conclusions:
The new KAS resulted in a substantial increase in allocation of PHS increased-risk kidneys to candidates in younger age groups. Because increased-risk kidneys are generally underutilized, future efforts to optimize the utilization of these organs should target younger recipients and their providers.
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