Long-term followup of bilateral high (Sober) urinary diversion in patients with posterior urethral valves and its effect on bladder function

Purpose: Although valve ablation is the treatment of choice in patients with posterior urethral valves (PLTV), temporary high (ureterostomy) diversion remains controversial. In this study we evaluated the effect of bilateral Sober high urinary diversion on renal and bladder function. Materials and Methods: We retrospectively reviewed the records of 36 patients with PUV who underwent bilateral Sober-type diversion. Following valve ablation urodynamic studies were done in all patients after diversion and repeated after ureterostomy closure. The mean duration of diversion was 55 months. Vesicoureteral reflux (VUR), renal dysplasia, serum creatinine during followup and urodynamic parameters were recorded. Results: All patients underwent endoscopic valve ablation. Renal function impairment at the end of followup was present in 15 patients. Renal dysplasia was found in 10 patients, while VUR was present in 16 at the time of the first urodynamic studies. Urodynamic studies after ureterostomy closure showed well preserved bladder capacity or compliance in 80% and 69% of cases, respectively. About a third of patients showed increased capacity and normal compliance. Univariate analysis showed that VUR, urinary tract infection and renal dysplasia significantly correlated with impaired renal function. On multivariate analysis renal dysplasia was an independent prognostic factor for poor prognosis. Conclusions: In patients with PLTV temporary high diversion of the Sober type does not have a negative influence on bladder function. It immediately releases high intrarenal pressures but only improves renal function temporarily and may contribute to postpone the time of end stage renal failure. Renal dysplasia dictates long-term renal outcomes in this group.