Prevalence of Interstitial Cystitis in Vulvodynia Patients Detected by Bladder Potassium Sensitivity

Abstract

Intravesical potassium sensitivity has been reported in 82% of vulvodynia patients, suggesting the bladder generates their pain and indicating interstitial cystitis (IC)/painful bladder syndrome deserves greater attention in differential diagnosis of vulvodynia. The aims of this study were to: (i) determine the prevalence of IC as detected by intravesical potassium sensitivity; and (ii) survey for urinary, pelvic pain, and sexually associated symptoms in patients with vulvodynia. Consecutive patients with vulvodynia were surveyed for urinary and pelvic pain symptoms using the pelvic pain and urgency/frequency (PUF) questionnaire, and tested for abnormal epithelial permeability using the potassium sensitivity test (PST). Rates of positive PST were determined overall and by PUF score range, and were compared in patients with intermittent vs. constant vulvodynia symptoms. Results of intravesical PST. Of 122 vulvodynia patients, 102 (84%) had a positive PST and 97 (80%) had urologic symptoms. Of the 87 sexually active patients, 81 (93%) reported pain associated with sex. Patients with constant (72/87, 83%) vs. intermittent symptoms (30/35, 86%) had no significant difference in rates of positive PST. Mean PUF score was 13.2. PUF scores of 3-4 were associated with an 86% rate of positive PST; scores 5-9, 44%; 10-14, 84%; 15-19, 87%; 20-24, 86%; and 25 and above, 100%. Most patients with vulvodynia have a positive PST and urgency/frequency, indicating pain of bladder origin (IC). IC deserves far greater consideration in the differential diagnosis of patients with vulvodynia. This represents a dramatic change for the gynecologic paradigm of vulvodynia, which in many cases appears to be referred pain from the urinary bladder.