Onabotulinum Toxin A Intradetrusor Injections in Children with Neurogenic Lower Urinary Tract Dysfunction: Long-Term Histological Effects on the Bladder Wall.

Background

In the last twenty-five years, Onabotulinum Toxin A (BTX-A) has gained increasing popularity for neurogenic lower urinary tract dysfunction (NLUTD) treatment. To maintain its efficacy, repeated BTX-A intradetrusor injections are required over time, with unknown effects on the bladder wall in children. The aim of this paper is to report long-term effects on the bladder wall in children treated with BTX-A.

Methods

Children with NLUTD not responsive to anticholinergics were treated with BTX-A, according to our protocol, with bladder wall control using endoscopic cold-cup biopsy. Specimens were evaluated considering edema, chronic inflammation, and fibrosis.

Results

Of the 230 patients treated from 1997 to 2022, we considered only specimens obtained in patients who had received ≥5 treatments (36 children), considered as the threshold to evaluate clinical effectiveness on long-term treatment with BTX-A. Most of them had congenital NLUTD (25 patients) and detrusor overactivity (27 patients). In all, increased edema and chronic inflammation with reduced fibrosis over time was reported; these data were not statistically significant. No difference was observed between patients with congenital and acquired diseases.

Conclusions

Repeated intradetrusor BTX-A injections are not related to significant histological alterations in children, similarly with adults, and repeated injections could be considered safe.