Ureteral obstruction after endoscopic treatment of the vesicoureteral reflux in children

Purpose - to investigate the ureteral obstruction (UO) frequency after endoscopic injection of the vesicoureteral reflux (VUR) in children. Materials and methods. 1068 children aged 8 months -15 years were respectively reviewed after endoscopic treatment of the VUR grades 2-4. The following factors were analyzed in terms of ureteral obstruction: age, sex, reflux grade. Also the clinical manifestations were reviewed as the ureteral obstruction management types (conservative - 28 (52.8%), stenting - (26.5%), reimplantation of the ureter - 11 (20.7%) as well. Statistical analysis of the frequency of OS (categorical data) was performed using nonparametric estimation methods (χ², Fisher's exact test). A difference of p<0.05 was considered statistically significant. Results. The total incidence of ureteral obstruction was 3.44% (53/1539 ureters). There were early (41 children) and late (12 children) obstructed units. The following risk factors for developing ureteral obstruction proved to be significant: sex (males), low reflux grade. The early UO was treated mostly with watchful waiting, stenting (13 cases) and 2 cases were submitted to open surgery. In late UO ureteral reimplantation was utilized (9 cases) as well as ureteral stenting was helpful. Conclusions. UO is an infrequent but essential complication of the endoscopic VUR correction. The early UO cases are effectively treated by watchful waiting with/without empty bladder or ureteral stenting. Ureteral reimplantation seems to be the main procedure in late UO cases. The research was carried out in accordance with the principles of the Helsinki Declaration. The study protocol was approved by the Local Ethics Committee of all participating institutions. The informed consent of the patient was obtained for conducting the studies. No conflict of interests was declared by the authors.