Is primary obstructive megaureter repair at risk for contralateral reflux?

Purpose: Contralateral vesicoureteral reflux occurs after successful unilat eral reflux repair in a significant proportion of patients without correlat ion to the surgical approach. Unilateral congenital obstructive megaureter was compared to primary vesicoureteral reflux with regard to the risk of on set of contralateral reflux after unilateral ureteral reimplantation. Materials and Methods: Unilateral congenital obstructive megaureter was dia gnosed in 58 consecutive patients 2 to 10 years old (mean age 3.2). Cross-t rigonal ureteroneocystostomy was performed in 57 cases and longitudinal ure teral reimplantation, according to the Politano-Leadbetter technique was do ne in 1. Longitudinal tapering according to Hendren was performed in 44 ure ters, and the Kalicinski folding was used to repair 11 ureters. All patient s underwent serial renal ultrasound, diethylenetetraminepentaacetic acid nu clear scan, excretory urogram and voiding cystourethrogram. The control gro up was composed of 98 age matched children with unilateral vesicoureteral r eflux who underwent unilateral reimplantation with or without tapering. Fis her's exact test and Student's t test were used for statistical analysis. Results: Followup ranged from 1 to 5 years. All patients in both groups und erwent a voiding cystourethrogram at 6 months, and renal ultrasound at 3, 6 and 12 months postoperatively. Grade 2 reflux developed in 1 study group p atient after contralateral Kalicinski ureteral folding and cross-trigonal r eimplantation (1.7%;). In the control group new onset contralateral reflux developed in 11 cases (11.2%). The difference was statistically significant (p <0.005, Fisher's exact test p = 0.033). Conclusions: Ureteral reimplantation for unilateral congenital obstructive megaureter is not correlated with the development of contralateral reflux. The occurrence of contralateral reflux after successful unilateral reflux r epair is high (11.2%), and is not correlated with age, sex and technique of reimplantation or tapering. These results support the hypothesis that the functional anatomy of the trigone is preserved in congenital obstructive me gaureter but is impaired on both sides in cases of unilateral vesicouretera l reflux. The surgical management of unilateral primary vesicoureteral refl ux and congenital obstructive megaureter should be differentiated based on these results.