Potassium sensitivity test predicts hydrodistention efficacy in patients with bladder pain syndrome/interstitial cystitis.

ObjectiveTo determine the possible role of potassium sensitivity test (PST) in predicting the success of hydrodistention (HD) in patients with bladder pain syndrome/interstitial cystitis (BPS/IC).Material and methodsPatients who underwent PST before diagnostic cystoscopy and HD were evaluated to collect data regarding the visual analog score (VAS) to assess pain, the voiding diary for frequency of urination/nocturia, mean urine volume per void, interstitial cystitis symptom index, and problem index before HD. Patients were requested to provide the VAS of pain at 1 month and 6 months post-HD. A reduction 2 or more on the VAS of pain was considered as a response adequate to be noted.ResultsThe median age of the patients was 46 years. The PST was positive for 27 patients (27/39; 69.2%). At 1 month post-HD, out of the 27 patients with positive PST, 23 (85.2%) were found to have been responsive to HD and 4 (14.8%) were non-responsive. Of the 12 (12/39; 30.8%) patients who showed a negative PST, 7 (58.3%) were non-responsive and 5 (41.7%) were responsive to HD. A logistic regression analysis revealed that PST (p=0.009) was the only parameter that was able to predict HD efficacy at 1 month post-HD.ConclusionPST was found to be a predictive factor for the short-term efficacy of HD. BPS/IC patients with positive PST are likely to be more susceptible to the damage of mucosal afferent nerve endings, which results in them benefiting from HD to a greater degree.