Intra-detrusor injections of botulinum toxin type a in children with spina bifida: A multicenter study

Introduction/Background Intradetrusor injections of botulinum toxin type A (IDBTX-A) have become the gold standard in adults for treatment of neurogenic detrusor overactivity refractory to anticholinergics. Data regarding IDBTX-A in pediatric patients with spinal dysraphism are scarce. The purpose of this study was to assess the effectiveness of IDBTX-A in children with spina bifida. Material and method All patients aged under 16 years old who underwent IDBTX-A between 2002 and 2016 at six institutions were included in a retrospective study. Our primary endpoint was the injection's success defined subjectively as both clinical improvement (no incontinence episodes between clean intermittent catheterization (CIC), absence of urgency, less than 8 CIC per day) and urodynamic improvement (resolution of detrusor overactivity, 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. Thirty-three (62.3%) had repeated injections (from 2 to 8 injections) resulting in a total number of 141 IBTX-A performed. 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  = 0.002). The clinical success rate was 66% and was significantly associated with maximum urethral closure pressure (34 cm vs. 54.4 cm H 2 O; P  = 0.02). The urodynamic success rate was 34%. Patients with closed spinal dysraphism had higher success rate vs. patients with myelomeningocele (48.2% vs. 17.4%; P  = 0.02). Patients in whom the first IDBTX-A succeeded urodynamically had higher baseline bladder compliance (15.5 ml/cm H 2 O vs. 7 ml/cm H 2 O; P  = 0.02). Maximum cystometric capacity ( P P  = 0.01) significantly improved after the first IDBTX-A. After a mean follow up of 3.7 years, 23 patients (43.4%) required augmentation cystoplasty. Conclusion Despite IBTX-A enabled clinical improvement in most patients (66%), urodynamic outcomes were poor, resulting in a low global success rate (30%).