Overactive bladder in children should be strictly differentiated from monosymptomatic nocturnal enuresis.

INTRODUCTION: To elucidate the prevalence of concomitant overactive bladder in children with a chief compliant of primary enuresis, and to evaluate the pathogenetic difference between monosymptomatic and non-monosymptomatic enuresis.

MATERIALS AND METHODS: All patients had evidence of primary enuresis. Neurogenic bladder was excluded. Urinary symptoms were evaluated by taking a history from the affected children and parents, and using a questionnaire and bladder diary. Voiding cystourethrography was performed for non-responders to exclude urinary abnormalities.

RESULTS: Eighty-eight patients (9.8 +/- 3.1 years old) were enrolled. Initial assessment demonstrated that 24% had undervalued overactive bladders and 9% had constipation. Voiding cystourethrography was performed in 25%, demonstrating mechanical urethral obstructions in 8% and vesicoureteral reflux in 4.5%. Constipation, a history of urinary tract infections, mechanical obstructions and vesicoureteral reflux were strongly associated with non-monosymptomatic enuresis.

CONCLUSIONS: Patients with non-monosymptomatic enuresis had a different clinical background, therapeutic response and pathogenetic abnormalities. In children an overactive bladder should be strictly differentiated from monosymptomatic enuresis.