Urine Neutrophil Gelatinase Associated Lipocalin as a Predictor of Vesicoureteral Reflux and Renal Parenchymal Damage: A Systematic Review

Background: Vesicoureteral reflux (VUR) is the most common congenital urinary tract abnormality in children. Renal parenchymal damage is the most devastating complication of severe undiagnosed VUR. Different diagnostic biomarkers have been introduced as alternatives for radiologic evaluation in these patients. This review article aimed to increase the knowledge about the role of urine neutrophil gelatinase-associated lipocalin (uNGAL) in children affected by primary VUR and renal parenchymal damage. Methods: A systematic review of PubMed, Scopus, Web of Science, ProQuest, and Ovid was conducted in September 2022 to retrieve studies that investigated the correlation between uNGAL or uNGAL/Cr excretion and primary VUR in male/female patients younger than 18 years of age. Patients with secondary VUR, age older than 18 years, infectious or inflammatory disorders, obstructive uropathies, and acute or chronic kidney diseases were excluded. Two reviewers independently screened the titles and abstracts of the search results and then assessed the full texts selected from the pertinent studies. Results: Eighteen research articles with a total sample of 699 patients were found to measure uNGAL in VUR or renal scarring. UNGAL or uNGAL/Cr had increased excretion in the majority of children with primary VUR or RPD, with a positive or no correlation to the severity of VUR. Conclusions: Several studies addressed uNGAL and uNGAL/Cr as putative biomarkers for the prediction of VUR or reflux-associated RPD.