[Pharmacological treatment of neurogenic detrusor hyperactivity: intradetrusor botulinum toxin A injections]

Botulinum toxins are among the most powerful of all natural poisons. They are responsible for human botulism and constitute potential chemical weapons, but are nevertheless used as therapeutic agents in an increasing number of indications and medical specialties. Botulinum toxins were used for the first time in urology by intrasphincteric injection by Dykstra in 1988 to treat detrusor-sphincter dyssynergia in spinal cord injury patients. Schurch performed the first intradetrusor injections in 2000 to treat incontinence due to overactive bladder in adult spinal cord injury or multiple sclerosis patients. This review of the literature presents the results and level of proof for the use of botulinum toxin intradetrusor injection to treat neurogenic voiding disorders. Botulinum toxin A intradetrusor injections constitute a safe, conservative, reversible and short-term effective (6-12 months) alternative after failure of anticholinergic therapy for overactive bladder and its clinical consequences in adult spinal cord injury or multiple sclerosis patients (level 1b) and in children with neural tube defects (level 4). The efficacy of the first injection appears to be maintained at subsequent injections (up to 10 cycles) (level 4). Convergent and longer-term data are necessary to document and more clearly define the medium- and long-term efficacy profile of this approach, currently considered to be a major progress in neurourology.