To find out what constitutes the true cutoff value, we need further studies enrolling patients with normal or impaired renal function in both patients developing AKI and those without AKI.38 Although there are limited data on NGAL measurements after PCI, the predictive role of NGAL in the early diagnosis of CIN has already been shown in adults and children undergoing coronary angiography.37, 39, 40. This evidence concerns the gene LCN2 and acute kidney injury.