Urodynamics investigation on children with vesicoureteral reflux identifies overactive bladder and poor compliance in those with voiding dysfunction

Up to 50% of children with vesicoureteral reflux (VUR) may have associated voiding dysfunction. It is thought to be an important determinate of the severity and resolution of VUR; however, to date there has been no objective measurement defining the impact of voiding dysfunction in children with VUR. The purpose of this study is to compare the urodynamic parameters of children with VUR who have and do not have symptomatic voiding dysfunction. We performed a retrospective study of 138 children with a diagnosis of primary VUR who underwent urodynamic investigations. Information regarding patient demographics, grade and laterality of VUR and clinical history of bladder dysfunction were assessed. Urodynamic parameters recorded included detrusor overactivity, early and late compliance, voiding pressure, post-void residual volume and functional bladder capacity. Statistical analysis was performed using t Student analysis, Pearson's chi(2) test or Fischer's exact test, with a p < 0.05 as being significant. The mean age of the patients at the time of urodynamic evaluation was 5.8 years (SD 4.4). 30% had symptomatic voiding dysfunction based on the clinical history. Children without a history of voiding dysfunction had higher grades of VUR as compared to those with it (p = 0.002). Bladder hypertone, detrusor overactivity, detrusor hypereflexia and poor late bladder compliance presented a statistically significant higher incidence the incidence of bladder overactivity and poor late bladder compliance was higher in children with bladder dysfunction than those without it. Our findings suggest that voiding dysfunction does have objective and quantifiable effects on bladder dynamics. Urodynamic evaluation may play a role in the management of children with VUR by identifying those with bladder dysfunction secondary to abnormal voiding habits.