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.