Special considerations of the overactive bladder in children.

The overactive bladder (OAB) in children is defined as both involuntary detrusor contractions and urethral instability. The development of urinary control plays a key role in its incidence and in our understanding of its pathogenesis. It is seen in a number of conditions but by far is most common among patients with dysfunctional voiding. Urinary infection can be both a cause and an effect of OAB. In some instances, vesicoureteral reflux may result from detrusor overactivity because its successful resolution has been shown to depend on abolition of the hyperactivity. Early diagnosis and appropriate treatment can affect upper urinary tract function and drainage and ultimate bladder function. Recognition is noted via a thorough history and careful physical examination. Urodynamic assessment is indicated in neurologically normal children >5 years old and is combined with a voiding cystourethrogram in boys and a radionuclide cystogram in girls who have a history of recurrent urinary infection. Treatment consists of prophylactic use of anticholinergic agents in patients with neurologic dysfunction, as an early adjunctive measure in boys after ablation of posterior urethral valves, and in children with vesicoureteral reflux. The dose must be carefully titrated in children with cerebral palsy to prevent the appearance of elevated residual urine. Behavioral therapy and biofeedback techniques are effective alternatives to anticholinergic agents for children with dysfunctional voiding.