Background: Ureteropelvic junction obstruction (UPJO) is a common cause of pediatric hydronephrosis, yet only one-Third of affected children require surgery. Differentiating obstructive from non-obstructive cases remains challenging with current imaging methods. This systematic review and meta-Analysis evaluated the role of ureteric jets, assessed via color Doppler ultrasonography (USG), as an adjuvant diagnostic modality to complement gray-scale USG in children with UPJO.

Materials and Methods: A systematic search of PubMed, Embase, Scopus, and Web of Science databases was conducted to identify studies reporting on ureteric jet frequency (UJF) in UPJO. Standardized mean difference (SMD) with 95% confidence intervals (CI) was calculated for the pooled data, while the I² statistic assessed heterogeneity. Methodological quality was evaluated using the Newcastle-Ottawa scale. Results: Five studies (111 patients) met inclusion criteria. Ureteric jets were absent in 67.3% of UPJO cases, with diagnostic accuracy reaching 94%. Meta-Analysis revealed a significant reduction in UJF in obstructed kidneys (SMD =-2.01, 95% CI:-3.09 to-0.94, P = 0.0002), though heterogeneity was substantial (I² = 80%, P = 0.006). The methodological quality of the included studies was good in four studies and poor in one study. Conclusions: The current systematic review demonstrated the absence of ureteric jets and a significant

reduction in the UJF in the obstructed kidneys. However, due to heterogeneity among the included studies, further studies are needed to standardize the protocols before any definite conclusions are drawn.