If patient develops a confirmed elevated urine CXCL10 level and is considered high risk for rejection, they will proceed to Randomization in the Intervention Phase, which can occur anytime between 2 weeks - 9 months post-transplant. Participants in the Intervention Arm will undergo renal biopsy to check for rejection. Biopsy-proven subclinical rejection will be treated per study protocol. Participants in the Control Arm will continue routine post-transplant surveillance with serum creatinine and proteinuria; serial urine samples will continue to be collected and analyzed (blinded), but not used to direct care. All randomized participants will undergo a 12-month study exit visit with protocol biopsy to determine primary, secondary and long-term outcomes.