Urinary neutrophil-gelatinase associated lipocalin is a more prognostic biomarker to distinguish antenatal hydronephrosis in neonates

Background and Aim: Routine diagnostic methods of Vesicoureteral reflux (VUR) are invasive and can cause exposure to radiation and may increase risk of urinary tract infections. Therefore, introducing reliable, non invasive methods might be more interested in pediatric nephrology. The objective of this perospective case control study was to evaluate the prognostic value of urinary neutrophil-gelatinase associated lipocalin (uNGAL) on antenatal hydronephrosis (AH) with and without VUR. Methods: A total of 50 patients diagnosed with AH; 78% males with mean age 5.71± 2.1 years, including 27 AH with VUR and 23 AH without VUR, and 19 normal healthy children; 78.9% males with mean age 5.63 ± 1.89 years, were enrolled in this study. Urinary NGAL levels were measured by enzyme linked immunosorbent assay (ELISA). Results: There was a significant difference in uNGAL concentration between AH patients and controls (0.80 ± 0.26 and 0.29 ± 0.27 ng/ml, p < 0.0001). However, the levels of uNGAL was not significantly deviated between AH patients with VUR compared to those without VUR (0.84 ± 0.34 vs. 0.75 ± 0.13, p=0.419). Standardization of NGAL based on urinary creatinine (uNGAL/uCr) showed a significantly difference between AH neonates with VUR compared to those without VUR (2.43±1.61 vs. 1.91±0.79, p < 0.0001). Receiver operator characteristic (ROC) analysis revealed higher prognostic power of uNGAL for identifying AH with a sensitivity; 95.7%, and specificity; 84.2%. Meanwhile, the levels of uNGAL or NGAL/uCr ratio did not correlate with reflux grade or laterality. Conclusions: The urinary level of NGAL and NGAL/Cr ratio might be a surrogate non invasive, reliable tool to distinguish hydronephrosis.