Allocation of Kidney Allografts From Donors With Kidney Donor Profile Index <35% and the Impact of Kidney Donor Profile Index Revisions on Access to Transplantation for Children.

RATIONALE &

objectiveChildren in the United States receive priority for kidneys with a kidney donor profile index (KDPI) < 35%, although their priority falls below that of certain adult recipients. Recently, the KDPI was revised to include 8 donor characteristics instead of 10. We sought to (1) describe the allocation of these high-quality kidneys and (2) compare the characteristics of donors with a KDPI < 35% using the original KDPI (KDPI-10) versus the revised KDPI (KDPI-8) calculation. STUDY

designRetrospective cohort study. SETTING &

participants60,587 deceased donors and their kidney recipients in the Organ Procurement and Transplantation Network registry between January 1, 2018, and December 31, 2023. EXPOSURE: KDPI calculated using KDPI-10 and KDPI-8 (without race and hepatitis C virus [HCV]). OUTCOME: The primary outcome was the use of kidneys with a KDPI < 35% overall. Secondary outcome was the utilization of kidneys from "ideal pediatric-quality donors" who were defined as having a KDPI < 35%, diagnosed with brain death, were aged <35 years, had a creatinine level ≤ 1.5 mg/dL, and had no infectious risk, diabetes, or hypertension. Additionally, we assessed the changes in characteristics of KDPI < 35% donors after revision to the KDPI. ANALYTICAL APPROACH: Descriptive statistics.

resultsDuring the study period, 23.4% of KDPI-10 < 35% and 34.3% of ideal pediatric-quality, KDPI-10 < 35% kidneys were transplanted into adults in allocation categories that receive more priority than children. Nearly three-quarters of these adults were multiorgan recipients. Compared with the KDPI-10 calculation, the donors with a KDPI < 35% using the KDPI-8 calculation were more often Black (15.3% vs 9.9%), HCV seropositive (11.1% vs 3.6%), and less frequently donated after circulatory death (12.7% vs 20.3%). The proportion of KDPI < 35% donors who are ideal pediatric-quality was similar (32.7% KDPI-10 vs 33.5% KDPI-8). LIMITATIONS: Extrapolation of KDPI-8 donor characteristics using a historical cohort.

conclusionsMany ideal pediatric-quality kidneys are allocated to adults, primarily multiorgan transplant recipients. We anticipate no meaningful change in the proportion of ideal pediatric-quality kidneys prioritized for children using the revised KDPI-8 calculation. PLAIN-LANGUAGE SUMMARY: Children with end-stage kidney disease are intended to have priority for kidneys from the best-quality kidney donors. However, their priority may fall below adult candidates who need multiple organs or are highly sensitized. Only about one-third of donors prioritized for children are ideal pediatric quality, meaning they come from young donors with minimal risk of kidney dysfunction. About one-third of these top-quality kidneys are transplanted into adults with more priority than children, most often transplanted into recipients receiving more than 1 organ transplant. Recently, the risk index used to determine which kidneys are prioritized for children was revised by excluding donor race and donor infection with hepatitis C. Our study suggests this change will not substantially affect the proportion of ideal pediatric-quality kidneys offered to children.