Intradetrusor Injections of Botulinum Toxin Type A in Children With Spina Bifida: A Multicenter Study

Abstract : OBJECTIVE: To assess the effectiveness of intradetrusor injections of botulinum toxin type A (IDBTX-A) in children with spina bifida. METHODS: All patients aged less than 16 years old who underwent IDBTX-A between 2002 and 2016 at 6 institutions were included in a retrospective study. Our primary endpoint was the success rate of IDBTX-A defined as both clinical improvement (no incontinence episodes between clean intermittent catheterizations [CICs], absence of urgency, and less than 8 CICs per day) and urodynamic improvement (resolution of detrusor overactivity and normal bladder compliance for age) lasting ≥12 weeks. Predictive factors of success were assessed through univariate analysis. RESULTS: Fifty-three patients with a mean age of 8.5 years were included. All patients were under CIC and 88.7% had received anticholinergics with either poor efficacy or bothersome adverse events. The global success rate of the first injection (clinical and urodynamic) was 30%. Patients with closed spinal dysraphism had a significantly better success rate than patients with myelomeningocele (P = .002). The clinical success rate was 66% and was significantly associated with maximum urethral closure pressure (34 cm H2O vs 54.4 cm H2O, P = .02). The urodynamic success rate was 34%. Maximum cystometric capacity (P <.0001) and compliance (P = .01) significantly improved after the first IDBTX-A and maximum detrusor pressure tended to decrease (P = .09) except in the subgroup of patients with poor compliance. After a mean follow-up of 3.7 years, 23 patients (43.4%) required augmentation cystoplasty. Excluding 6 patients who were lost to follow-up, 38.3% of patients were still undergoing botulinum toxin injections at last follow-up. CONCLUSION: In this series, despite the fact that IDBTX-A enabled clinical improvement in 66% patients, urodynamic outcomes were poor resulting in a low global success rate (30%).