Risk Factors for Treatment Failure after Endoscopic Subureteral Injection of Dextranomer/ Hyaluronic Acid Copolymer (Deflux Ⓡ ) for Vesicoureteral Reflux

Ⓡ ) has become an established alternative to long-term antibiotic prophylaxis and open ureteral reimplantation for the management of vesicoureteral reflux (VUR) in children. We retrospectively evaluated the risk factors for treatment failure after endoscopic correction of VUR. Materials and Methods: Between 2005 and 2007, 23 boys and 26 girls (total of 69 ureters) with VUR underwent endoscopic subureteral injection of Deflux Ⓡ primarily. VUR was unilateral in 29 patients and bilateral in 20 patients. Of the 69 ureters, VUR was grade II to V in 13, 28, 20, and 8, respectively. Follow-up urinalysis and ultrasonography were performed 1 and 3 months after the procedure, and a voiding cystourethrogram was performed at 6 or 9 months postoperatively. Results: Treatment failure was defined as persistent VUR of grade II or over grade II. Endoscopic correction failed in 22 of 69 refluxing ureters. Age, sex, laterality, number of preoperative urinary tract infections, time from diagnosis to operation, presence of renal scarring, and injection volume did not influence outcome. However, preoperative presence of voiding symptoms, high-grade reflux and hydronephrosis, and having a horseshoe or golf-hole shaped ureteral orifice had a negative influence on the treatment result by univariate analysis. Severe dilatation of the lower ureter was the only statistically significant factor by multivariate analysis. Conclusions: Severity of lower ureteral dilatation is the most significant factor influencing the failure of endoscopic subureteral injection of Deflux Ⓡ .