Retrospective study of endoscopic treatment in children with primary vesicoureteral reflux and multivariate analysis of factors for failure.

OBJECTIVE: The aim of this study was to investigate endoscopic treatment in children with primary vesicoureteral reflux (VUR) and conduct a multivariate analysis of factors for failure. MATERIAL AND METHODS: Between August 2006 and January 2012, 216 children (32 boys and 184 girls) with primary VUR (grades I-IV) who underwent endoscopic treatment were analysed. Patients with grade V VUR were excluded. Hydrodistension tests and intraureteral injection techniques were performed, if applicable. Urinary ultrasound and voiding cystourethrography were studied 3-6 months after surgery. Univariate and multivariate logistic regression were used for statistical analyses. RESULTS: In total, 172 children (21 boys and 151 girls) were enrolled, and 280 ureters were treated (108 bilateral, 64 unilateral; three with grade I, 34 with grade II, 214 with grade III and 29 with grade IV VUR). The median (± SD) age was 7.8 ± 3.1 years (boys 7 ± 3.1 years, girls 7.9 ± 3.1 years). The mean (± SD) follow-up was 24.4 ± 4.1 months (boys 28.2 ± 8.1 months, girls 21.4 ± 4.1 months). Mean injected volume per ureter was 1.8 ± 0.5 ml. A single injection resolved the reflux in 79.6% and a second injection resolved it in 90.4% of ureters. Eight children (4.6%) had postoperative febrile urinary tract infections (fUTIs). Postoperative fUTIs were significantly associated with failures in injection (p < 0.001). Renal scars were significantly associated with postoperative fUTI (p = 0.006). Haematuria occurred in three children (minor complication); a non-functional kidney was observed in one child (major complication) and a laparoscopic nephrectomy was performed. Fourteen children underwent ureteroneocystostomy owing to unsuccessful VUR treatment. CONCLUSIONS: Endoscopic injection of small-diameter microsphere (80-120 µm) non-animal dextranomer-hyaluronic acid copolymer seems to be an effective treatment for VUR. Only postoperative fUTI and the presence of a renal scar were correlated with failed endoscopic treatment of VUR.