Objectives: Children undergoing cardiopulmonary bypass (CPB) are at risk of acute kidney injury (AKI). Rise in serum creatinine occurs slowly and late, hence other markers are crucially needed to recognize AKI early. The aim of the study is to detect the efficacy of Neutrophil gelatinase-associated lipocalin (NGAL) in the early prediction of AKI.
Methods: A prospective observational study with enrollment of 174 patients, aged 6 months to 60 months, with congenital heart disease, undergoing CPB. Plasma NGAL measurement preoperatively and serially at 2, 12, 24, 36, and 48 hours post-CPB initiation. Patients were classified into 2 groups according to the development of postoperative AKI.
Results: Plasma NGAL levels post-CPB were significantly higher in the AKI group compared to the non AKI group with positive significant correlations between plasma NGAL level and severity of AKI. A rise in plasma NGAL of 500% from its preoperative basal level, when measured at 2 hours post-CPB initiation (NGAL 2-0 index), shows sensitivity and specificity of 83% and 64% respectively (AUC=0.667) and at 12 hours post-CPB initiation (NGAL 12-0 index) shows sensitivity and specificity of 66% and 64% respectively (AUC=0.762).
Conclusions: Plasma NGAL is a predictive biomarker for acute kidney injury after pediatric cardiac surgery, and it may permit earlier intervention that improves the outcome of AKI. A 500% rise in plasma NGAL at 2 hours post-CPB initiation from its basal preoperative level (NGAL 2-0 index) is a precise, sensitive, and early predictor of AKI in children.