Preliminary results of suburothelial injection of botulinum a toxin in the treatment of chronic interstitial cystitis.

PURPOSE: Treatment of interstitial cystitis is usually not successful in eradicating bladder pain and increased bladder capacity. This study was designed to evaluate the clinical effectiveness of suburothelial injection of botulinum A toxin in patients with chronic interstitial cystitis.

METHODS: Eight women and 2 men with chronic interstitial cystitis who had failed conventional treatments were enrolled in this study. In 5 patients, 100 units of botulinum A toxin was injected suburothelially into 20 sites, and an additional 100 units was injected into the trigone in the other 5 patients. Therapeutic outcome including functional bladder capacity, number of daily urinations, bladder pain, and urodynamic changes were compared between baseline and 3 months after treatment.

RESULTS: In 2 patients bladder pain and urinary frequency were improved 3 months after treatment. Mild difficulty in urination was reported by 7 patients. Functional bladder capacity recorded in a voiding diary was significantly increased (155+/-26.3 vs. 77+/-27.1 ml, p<0.001), and the frequency of daily urinations (18+/-7.7 vs. 24.2+/-10.3, p=0.025) and the pain score (2.4+/-1.6 vs. 3.2+/-1.1, p=0.003) were mildly but significantly reduced after treatment. Only the cystometric capacity improved significantly (287+/-115 vs. 210+/-63.8 ml, p=0.05) in urodynamic results. Trigonal injection had no therapeutic effect on symptom or urodynamic improvement. No adverse effect was reported.

CONCLUSIONS: The clinical result of suburothelial botulinum A toxin injection was disappointing. None of the patients was symptom free and only a limited improvement in bladder capacity and pain score was achieved in 2 patients.