[Urination disorders revealing posterior urethral valve: clinical aspects].

One hundred sixty-four boys presenting with voiding dysfunction without any obvious uropathy or neuropathy were enrolled in a prospective study. Nine (5.5%) were suspected to have urethral valves after video-urodynamic assessment, later confirmed by cystoscopy. Those with proven posterior urethral valves were compared to a control group of boys without urethral obstruction. There was no difference in anamnesis nor clinical presentation between the two groups. Even on uroflowmetry the urethral valves were not suspected; only the urodynamic assessment could distinguish the obstructed from the non-obstructed boys. Although there remains controversy about the existence of posterior urethral valves in functional voiding disorders in boys, we could demonstrate that after a complete prospective screening such a rare combination occurs in around 5% of the cases.