Long-term follow-up after botulinum toxin A (BTX-A) injection into the detrusor for treatment of neurogenic detrusor hyperactivity in children

Purpose. To prove the long-term efficacy of BTX-A injection in the management of children with neurogenic detrusor hyperactivity. Materials and methods. 28 out of 145 children with neurogenic bladder (15 male and 13 female, mean age 10.7 years) who were treated between 2002 and 2010 and became non-responders to conservative treatment were included into the retrospective study. We injected 10-12 U/kg of BTX-A (Botox (R)) into the detrusor at 20-30 sites, sparing the trigone. The mean follow-up was 48 months (range 6-84 months). Results. Group 1. 14 patients had a single injection of BTX-A. Five of them were successful. Mean bladder reflex volume increased (from 62.9 to 117.5 ml), maximum detrusor pressure decreased (from 59 to 37.5 cm H2O), detrusor compliance increased (from 4.8 to 9.5 ml/cm H2O), and leak-point-pressure decreased (from 46.5 to 24.2 cm H2O). Four patients did not respond and were treated by ileocystoplasty. Another five were lost to follow-up. Group 2. 14 patients had repeated (mean 2.5) injections of BTX-A with a mean interval of 13.7 months. In thirteen patients, urodynamic parameters of the first and last injection were similar to those obtained in Group 1, showing a good response. One patient received an ileocystoplasty. Conclusion. BTX-A is a safe alternative in the treatment of detrusor hyperactivity in children with myelomeningocele (MMC). The efficacy lasted a mean of 12 months and urodynamic response was unchanged even after several injections. In our series, 21.7% of children with severe low-compliance bladders were non-responders.