Rapid Urine Biomarker Panel Supports Better Kidney Transplant Decisions

In the United States, more than 92,000 people are awaiting a kidney transplant, yet nearly one in four recovered donor kidneys goes unused each year. Allocation decisions often rely on the Kidney Donor Profile Index (KDPI), which has only modest ability to predict long-term outcomes. A new study shows that adding a rapid urine biomarker test from donors can improve kidney quality assessment and potentially reduce organ non-utilization.

Johns Hopkins Medicine evaluated a three-biomarker urine panel—uromodulin, osteopontin, and YKL-40—used alongside the KDPI to assess deceased-donor kidney quality. The approach combines biomarker signals from donor kidney urine with the KDPI to estimate the likelihood of favorable long-term function. The study indicates this biomarker‑enhanced assessment can provide transplant teams with greater confidence when considering kidneys that might otherwise be declined.

Measurements were obtained using standard immunoassays or rapid lateral flow devices, with the point-of-care format delivering results within 30 minutes to fit fast-paced organ procurement workflows. The analysis focused on combining these biomarker measurements with KDPI to improve assessment of donor kidney quality and support allocation decisions.

The multicenter observational study enrolled deceased kidney donors between 2010 and 2013 through five organ procurement organizations and followed paired kidney transplant recipients for three years. Investigators analyzed 474 deceased donors whose kidneys were transplanted into two separate recipients, enabling a more precise assessment of how donor organ quality influences long-term outcomes. Using data from more than 1,500 deceased donors, researchers also modeled the clinical decision-making impact of adding the biomarker panel.

Adding the three urinary biomarkers to KDPI improved prediction accuracy from 80% to 86%. The method increased identification of kidneys likely to have favorable outcomes by 10 percentage points while maintaining 78% specificity. Modeling suggested the approach could reduce unnecessary kidney biopsies in about 20% of donors and return at least one kidney to the pool in roughly 7%; in a hypothetical cohort of 10,000 deceased donors, that equates to more than 2,000 fewer biopsies and approximately 700 additional kidneys available for transplantation.

Findings were published in the Journal of the American Society of Nephrology on July 9, 2026. Collaborating institutions included the University of Washington, Columbia University, Yale University, Vanderbilt University Medical Center, the University of Michigan, and CommonSpirit Health. The authors note that, while observational, the results illustrate a path toward incorporating real-time biological measures into existing allocation systems.

“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.” said Chirag R. Parikh, M.D., Ph.D., director of the Division of Nephrology at the Johns Hopkins University School of Medicine.

“Every kidney that is donated but not transplanted is a patient who stays on dialysis. If a test that is inexpensive and takes minutes can return even a portion of those organs to the pool, that matters enormously to the people who are waiting for a kidney transplant. Our next step is to prove it prospectively, in real time, at the point of donation,” Parikh added.

Related Links
Johns Hopkins Medicine