Detection of Kidney Allograft Rejection Using Urinary Chemokines

Area of Science:

• Nephrology
• Transplantation Immunology
• Biomarker Discovery

Background:

• Urinary chemokines CXCL9 and CXCL10 are potential biomarkers for kidney allograft rejection.
• Their added value over standard monitoring protocols requires further investigation.

Purpose of the Study:

• To evaluate the clinical utility of urinary CXCL9 and CXCL10 in detecting kidney allograft rejection.
• To determine if these chemokines provide additional diagnostic value beyond current standard of care monitoring.

Main Methods:

• Prospective enrollment of 733 kidney transplant recipients across 7 centers.
• Quantification of urinary CXCL9 and CXCL10 via immunoassay at the time of biopsy.
• Allograft rejection classified using the Banff 2019 criteria.

Main Results:

• Urinary CXCL9 and CXCL10 showed moderate performance (AUROC 0.70 and 0.64) for rejection detection.
• Adding CXCL9 to standard models improved discrimination but not overall fit.
• CXCL10 provided no additional value; sensitivity analyses confirmed limited utility.

Conclusions:

• Urinary CXCL9 has limited clinical utility for detecting kidney allograft rejection.
• Urinary CXCL10 does not offer additional value beyond standard monitoring in the first year post-transplant.