RESUMO
PURPOSE: The Aim of this study was to find the value of intravesical permeability of potassium as a diagnostic measure of the interstitial cystitis and to find importance of intravesical mucosal layer by intravesical instillation of potassium chloride solution. MATERIALS AND METHODS: 20 patients with interstitial cystitis and 20 normal subjects without UTI, frequency and urgency underwent intravesical challenge with 40ml water and 40ml of 400meq/L potassium chloride solution. After 5 minutes, patients were asked about increase or decrease of urgency or suprapubic pain and subjective response of urgency or suprapubic pain were recorded on a scale of 0 to 5. RESULTS: Neither normal subjects nor patients with interstitial cystitis reacted to water administered intravesically. There was marked sensitivity to intravesical potassium in 85% of patients with interstitial cystitis versus 10% of normal controls (p<0.05). CONCLUSIONS: Diffusion of urinary potassium ion into the bladder interstitium may induce sensory symptoms, damage the tissue and be a major toxic factor in the pathogenesis of interstitial cystitis. Intravesical potassium sensitivity can be a reliable method for detecting abnormal epithelial permeability and useful diagnostic test for interstitial cystitis.