Congenital anomalies of the kidney and urinary tract (CAKUT) is a main cause leading to endstage renal disease (ESRD) during childhood occurring at a frequency of 1 in every 500 pregnancies. No early predictive markers of long-term renal function (RF) are validated in these neonates. The aim of this study was to compare CysC and creatinine (creat) as markers of RF from birth to 2 years and to identify factors of RF progression.