Iothalamate versus estimated GFR in a Hispanic-dominant pediatric renal transplant population

Background: Accurate knowledge of glomerular filtration rate (GFR) is essential to the practice of nephrology. Routine surveillance of GFR is most commonly executed using estimated GFR (eGFR) calculations, most often from serum creatinine measurements. However, cystatin C-based equations have demonstrated earlier sensitivity to decline in renal function. The literature regarding eGFR from cystatin C has few references that include transplant recipients. Additionally, for most of the published eGFR equations, patients of Hispanic ethnicity have not been enrolled in sufficient numbers. Methods: The applicability of several eGFR equations to the pediatric kidney transplant population at our center were compared in the context of determining whether Hispanic ethnicity was associated with equation performance. Results: Updated Schwartz, CKiD, and Zappitelli eGFR estimation equations demonstrated the highest correlations. Conclusions: The authors recommend further prospective investigations to validate and identify factors contributing to these findings.