[Botulinum toxin type A in patients with overactive bladder]

The aim of the study was to investigate safety and efficacy of intradetrusor injection of 100 units of botulinum toxin type A in 26 patients with refractory overactive bladder. The diagnostic scheme consisted of 72 h diary, laboratory tests, ultrasound investigation with measurement of residual urine, urodynamic investigation and neurological examination. The patients were divided into 3 groups: 14 patients with idiopathic detrusor overactivity (DO), 9 with neurogenic DO, and 6 with overactive bladder without DO. 100 units of botulinum toxin type A mixed with 20 ml of normal saline were injected into the detrusor sparing the trigone. Clinical and urodynamic evaluations were performed before the injection and 1, 3 and 6 months after it. The patients with idiopathic DO and overactive bladder without DO showed improvement of such clinical symptoms as frequency, urgency, nocturia and urgent incontinence which lasted for at least 6 months. Patients with neurogenic DO had improvement of the clinical symptoms only for one month after treatment. We had no patients who exhibited acute urinary retention or residual urine. Thus, 100 units of botulinum toxin type A injected into the detrusor is an effective, safe and well tolerated treatment for patients with idiopathic DO and overactive bladder without DO in whom an anticholinergic medication has failed.