Effects of Combination Treatment of Intravesical Resiniferatoxin Instillation and Hydrodistention in Patients with Refractory Painful Bladder Syndrome/Interstitial Cystitis: A Pilot Study

PURPOSE Painful bladder syndrome/interstitial cystitis (PBS/IC) is a disabling disease of the urinary bladder, and its etiology and treatment are not yet established. Current medications used in the treatment of PBS/IC have shown limited efficacy. This prospective study investigated the efficacy of intravesical resiniferatoxin (RTX) in PBS/IC refractory to medical treatment. METHODS Patients with proven PBS/IC refractory to traditional medical treatment were enrolled. By randomized trial, a total of 18 consecutive patients were divided into two groups: treatment with hydrodistention and intravesical RTX (group 1) or treatment with hydrodistension only (group 2). We assessed bladder pain by use of a visual analogue pain scale, the maximal urine flow rate, post-void residual urine volume, and a voiding diary before and 3 months after treatment. RESULTS The median age of the 18 patients was 55.8±6.9 years, and the median duration of symptoms before diagnosis was 3.6±1.6 years. Frequency, functional bladder capacity, and score on a 5-point pain scale were significantly improved at 3-month after treatment in both groups. Intravesical RTX instillation plus hydrodistention, compared with hydrodistention only, did not have a significant effect on the voiding symptoms or uroflowmetry of the patients but significantly improved scores on the pain scale. CONCLUSIONS Intravesical RTX instillation plus hydrodistention was effective in relieving pain but was not effective in improving lower urinary tract symptoms. Further larger studies are needed to clarify the efficacy of combination treatment of intravesical RTX instillation and hydrodistention.