[Injection of botulinum toxin (BTX-A) in children with bladder dysfunction due to detrusor overactivity]

bladder dysfunction causes urinary incontinence and kidney damage in children. When treatment with anticholinergics and intermittent bladder catheterization fails, the alternative therapy is bladder augmentation.

between 2005 and 2009, a prospective study was carried out with Botox(®) injected into the detrusor of children suffering from high-pressure bladder despite anticholinergic treatment. We assessed their urodynamic, clinical and radiological evolution prior to and at 4 weeks, 6 months and 1 year after the injection (10 u/kg of weight up to 300 u). Reinjection was indicated in the event of clinical or urodynamic worsening. We employed the Wilcoxom test to statistically analyze the urodynamic parameters.

12 patients were treated, 11 with neurogenic bladder (91.7%) and 1 with posterior urethral valves (8.4%). The mean age was 12.6 (4.3-17.8) years and follow-up took place after 40.8 (16.9-45-7) months. Bladder capacity, detrusor accommodation and pressure improved after 4 weeks in all the patients except in 2 (16.7%). This improvement decreased after 6 months, although successive injections produced similar changes. One patient (8.3%) received 1 dose, six (50%) two doses and five (41.7%) received three. Clinical and urodynamic improvement in 8 patients (66.7%) prevented bladder augmentation.

repeated botulinum toxin injection in the detrusor is a therapeutic instrument for high pressure and low accommodation bladders in children. It could replace bladder augmentation in some cases, however further studies with long-term follow-up care are required to appropriately evaluate its safety and effectiveness.