In what type of interstitial cystitis/bladder pain syndrome is DMSO intravesical instillation therapy effective?

BACKGROUND Dimethylsulfoxide (DMSO) is the most-used agent for intravesical instillation. We conducted this retrospective clinical study to determine in what type of the interstitial cystitis (IC)/bladder pain syndrome (BPS) DMSO was effective. METHODS We combined DMSO with hydrodistension in 2003 and from 2004 we performed hydrodistension alone. Hydrodistension had been performed in 7 cases of IC/BPS with Hunner's lesions (H group) and 7 cases of IC/BPS without Hunner's lesions (non-H group), and they served as the control group (C group; n=14). There was also a DMSO group (D group; n=14) that consisted of an H group of 7 cases and an non-H group of 7 cases in which the hydrodistension had been immediately followed by intravesical instillation of 50% DMSO 50 mL. Before, and 2, 6, 12, 18, and 24 months (M) after the intervention, the patients were asked to complete a 4-day frequency-volume chart (FVC) and the O'Leary-Sant IC symptom index (ICSI) questionnaire and IC problem index (ICPI) questionnaire, and to rate their pain on a visual analogue scale (VAS). RESULTS All parameters were improved after hydrodistension in both the C group and the D group. However, comparison of the C group and D group according to whether Hunner lesions were present showed that there were no significant differences in any of the postoperative parameters between the non-H groups in the C group and D group, but in the H groups, average and maximum voided volume were significantly higher and the ICSI, ICPI, and VAS scores were lower in the D group. Moreover, the significant differences increased with the duration of the postoperative period. CONCLUSIONS DMSO intravesical instillation therapy was useful in both maintaining and improving the effectiveness of hydrodistension in IC/BPS with Hunner lesions. However, DMSO did not have any particular efficacy in the treatment of IC/BPS in the absence of Hunner lesions.