RESUMO
PURPOSE: Primary bladder neck dysfunction has been under diagnosed as a treatable cause of vesicoureteral reflux. We evaluated the effect of prazosin administration on vesicoureteral reflux resolution and urodynamic parameters in children with idiopathic primary reflux and primary bladder neck dysfunction. MATERIALS AND METHODS: A total of 62 children (mean ± SD age 7.9 ± 2.4 years) with documented vesicoureteral reflux and urodynamics proved primary bladder neck dysfunction were randomized to receive either 0.025 mg/kg α-blocker (prazosin, 40 patients) or placebo (22) nightly for 1 week with a subsequent increase to 2 divided doses. Patients were followed for 12 months with clinical evaluation and uroflowmetry performed every 2 months, and each patient underwent complete urodynamic study at 6-month intervals. RESULTS: In the placebo group no uroflowmetry or urodynamic parameter changed significantly at 1-year followup. A 60% decrease in reflux grade was observed in the treatment group compared to 17% in the placebo group. Mean maximal detrusor pressure, post-void residual and opening time were significantly decreased in both followup sessions in the prazosin group (p <0.05). Average flow rate improved from 4.30 to 12.80 ml per second at 6 months and to 13.10 ml per second at 12 months (both p <0.05). CONCLUSIONS: Special attention should be given to secondary causes of vesicoureteral reflux (such as primary bladder neck dysfunction, an underdiagnosed entity in children), since conventional treatment will most likely fail if these conditions are not addressed promptly. In this study prazosin was effective therapy for children with vesicoureteral reflux and primary bladder neck dysfunction.
