Urodynamic assessment of children treated with botulinum toxin A injections for urge incontinence: a pilot study

Abstract

Objective. This study aimed to investigate changes in urodynamic findings and symptoms after detrusor injections of botulinum toxin A (BTX-A) in children with idiopathic detrusor overactivity (IDO) and urge incontinence. Material and methods. Eight girls and five boys, aged 7–19 years, who had urge incontinence refractory to scheduled voiding and anticholinergics, were included this prospective study. Urodynamic studies showed postoperative IDO in 12 patients. A dose of 50–100 IU (1.3–4.8 IU/kg) BTX-A was primarily administered at 15–20 detrusor sites. A control urodynamic study was performed within 3 months after the injections. Seven patients had a repeated procedure 16 (range 6–24) months on the average after the first one. Results. Eleven of the 13 patients had daily incontinence and two had incontinence a couple of times a week in association with urge symptoms. Postoperatively, no patient had urinary retention, but one girl had a urinary tract infection 4 months after the therapy. Five patients had a full response, seven partial responses and one no response 1–3 months after the first treatment. After 1 year, three of nine patients still have full response. Maximum cystometric capacity increased after the first treatment from a median of 227 ml to 379 ml (p = 0.005) and the number of patients with uninhibited detrusor contractions more than 30 cmH₂O during the filling phase decreased from eight to two out of 13 (p = 0.041). Conclusions. Intradetrusor BTX-A injections effectively reduce day-time wetting, significantly increase bladder volume and decrease detrusor overactivity in children with urge incontinence refractory to scheduled voidings and anticholinergics.

Key Words::

• bladder volume
• botulinum toxin A
• detrusor overactivity
• idiopathic wetting
• intradetrusor injections
• maximum cystometric capacity
• urodynamic testing

Acknowledgements

The study was supported in part through donation of the urodynamic device from Medan Inc. and through grants from and the Medical Research Fund of Tampere University Hospital.

Declaration of interest: The authors report no conflicts of interest. The authors alone are responsible for the content and writing of the paper.