More than one in four deceased-donor kidneys goes unused each year.1
One of the reasons for this is the uncertainty around the quality of the kidney. Clinicians often cannot be sure whether an organ that looks marginal will actually work once transplanted.
Research from Johns Hopkins Medicine suggests a better answer may already be available, and it lies within the urine from the deceased donor kidney.
What did the research find?
In this observational study, researchers analyzed deceased donor urine prior to organ procurement for three protein biomarkers: uromodulin, osteopontin and YKL-40. They then paired those results with the Kidney Donor Profile Index (KDPI), the standard score used to estimate the quality of deceased donor kidneys.
While the KDPI primarily draws on donor age and medical history, adding the three urinary biomarkers to KDPI improved prediction of long-term transplant function.2
Senior author of the study, Chirag R. Parikh, MD, PhD, explained in a press release from Johns Hopkins Medicine:
“We have been evaluating donor kidneys almost entirely on the donor’s history; their age, their diagnoses, a single creatinine value. These biomarkers tell us something the KDPI cannot: whether the kidney itself is repairing. That turns out to be a far better predictor of how it will work in a patient.”
Key Results
- The accuracy for predicting which kidneys would function well over time rose from 80% to 86%.
- The sensitivity for identifying viable kidneys improved by 10 percentage points.
A separate model using data from more than 1,500 deceased donors, sought to answer a practical question in transplant access: If transplant teams actually used this test, what would change?
The model projected approximately 20% fewer donor biopsies and at least one additional kidney recovered from roughly 7% of donors. Scaled to 10,000 deceased donors, that translates to more than 2,000 biopsies avoided and approximately 700 more kidneys available for transplant.
Learn more about the study’s findings and its methodology: Johns Hopkins Medicine | Simple Urine Test Could Improve Kidney Transplant Decisions and Save Hundreds More Donor Kidneys Each Year, Study Suggests
[1] OPTN/SRTR 2024 Annual Data Report: Deceased Organ Donation: https://www.sciencedirect.com/science/article/pii/S1600613526009913
[2] Thiessen Philbrook H, Kerr KF, Mohan S, et al. Donor Urinary Biomarkers and the Prediction of Deceased Donor Allograft Function Journal of the American Society of Nephrology. Published online July 9, 2026. doi:10.1681/ASN.0000001183
CLINICAL PERSPECTIVE
“This research points to the possibility of a practical and clinically impactful tool. Equipped with a real-time assessment of the kidney itself, rather than relying solely on donor history, clinicians can be more confident about accepting marginal kidneys that they might otherwise have turned down. When a kidney is declined due to uncertainty, someone stays on dialysis. But when science moves forward and helps expand the supply of transplantable kidneys, our patients move forward in their personal journeys, too.”
Michael O’Shea, MD
vice president, clinical leadership for DaVita Integrated Kidney Care