Prospective randomized controlled trial comparing fulguration versus fulguration and hydrodistension for Hunner-type interstitial cystitis/bladder pain syndrome

Purpose: In Hunner-type interstitial cystitis/bladder pain syndrome (IC/BPS), it is unclear whether suburothelial afferents underlying normal-appearing background areas contribute to symptom development. We examined whether adding hydrodistension (HD) to transurethral fulguration (TUF) of Hunner lesions, for the purpose of treating the background areas, is superior to TUF alone. Methods: This randomized controlled trial included 52 patients with Hunner-type IC/BPS allocated at a 1:1 (TUF:TUF+HD) ratio. HD was performed at 80 cmH₂O for 8 min before TUF in the TUF+HD group. Thirty-three patients remained until the end of the 6-month observational period. The primary endpoint was the visual analogue scale (VAS) pain score at 1 month. Major secondary endpoints were the treatment-failure rate, VAS pain scores at ≥ 2 months, and frequency-volume chart parameters. Results: Both TUF and TUF+HD showed significant improvement in VAS pain score at 1 month (95% confidence interval [CI]: − 1.62 to 0.16, P = 0.106). VAS pain scores were significantly lower in TUF+HD than TUF at 2 (95% CI: − 1.97 to − 0.28, P = 0.011), 4 (95% CI: − 2.83 to − 0.72, P = 0.002), and 6 (95% CI: − 3.11 to − 0.07, P = 0.040) months. Treatment-failure rate was higher in TUF (36.4%) than TUF+HD (17.4%), without significance (odds ratio: 2.714, 95% CI: 0.68 to 10.84, P = 0.189). Functional capacity and urgency were not significantly different between groups. Conclusion: The addition of HD to TUF tended to be superior to TUF monotherapy for controlling pain in Hunner-type IC/BPS. This indicates that not only Hunner lesions but also normal-appearing background areas may have a role in the pain of IC/BPS. Trial registration: ClinicalTrials.gov Identifier: NCT03987594, date of registration: 2019-06-17 (retrospectively registered).