Comparison of intravesical botulinum toxin type A injections plus hydrodistention with hydrodistention alone for the treatment of refractory interstitial cystitis/painful bladder syndrome

OBJECTIVE To compare the clinical effectiveness of botulinum toxin type A (BoNT-A) injections followed by hydrodistention (HD) with HD alone in patients with interstitial cystitis/painful bladder syndrome (IC/PBS). PATIENTS AND METHODS A prospective, randomized study was performed in a urological referral centre. In all, 67 patients with IC/PBS who had failed conventional treatments were enrolled. Of these, 44 patients received suburothelial injection with 200 U (15) or 100 U (29) of BoNT-A followed by cystoscopic HD 2 weeks later (BoNT-A groups). The control group (23 patients) received the identical HD procedure with no BoNT-A injection. All patients remained on baseline medications of pentosan polysulphate throughout the study. Bladder pain visual analogue scale (VAS), O'Leary-Sant symptom and problem indexes, functional bladder capacity (FBC) and urodynamic variables were measured at baseline and after treatment. Global response assessment was used to evaluate successful treatment response. RESULTS The IC/PBS symptom score significantly decreased in all three groups, but VAS reduction, FBC and cystometric bladder capacity increases were significant only in the BoNT-A groups at 3 months. Of the 44 patients in the BoNT-A group 31 (71%) had a successful result at 6 months. A successful result at 12 and 24 months was reported in 24 (55%) and 13 (30%) patients in BoNT-A group, respectively, compared with only six (26%) and four (17%) in the control group (P = 0.002). CONCLUSION Intravesical injections of BoNT-A followed by HD produced significantly better clinical results than HD alone in patients with IC/PBS.