Assessment of glomerular filtration rate (GFR) is essential for care following kidney transplantation, as it is the primary surrogate marker for clinical monitoring of allograft function and long-term transplant survival.1,2 Multiple GFR estimating equations have been proposed in the literature; however, they often do not include kidney transplant recipients in their derivation processes. Clearance measurements of exogenous filtration markers such as iothalamate and radiolabeled diethylenetriaminepentaacetic acid (99mTc-DTPA) remain specialized and expensive diagnostic tests limited by cost, inconvenience, and lack of availability.