Azar Nickavar - Department of Pediatric Nephrology, School of Medicine, Aliasghar Children’s Hospital, Iran University of Medical Sciences, Tehran, Iran.
Ehsan Valavi - Chronic Renal Failure Research Center, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
Nader Sadigh - Department of Emergency, School of Medicine, Aliasghar Children’s Hospital, Iran University of Medical Sciences, Tehran, Iran.

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 ۲۰۲۲ to retrieve studies that investigated the correlation between uNGAL or uNGAL/Cr excretion and primary VUR in male/female patients younger than ۱۸ years of age. Patients with secondary VUR, age older than ۱۸ 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 ۶۹۹ 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.

Vesicoureteral reflux, VUR, Urinary tract infections, UTI, Renal parenchymal damage, Renal scar, Renal scarring