Increased prevalence of interstitial cystitis: previously unrecognized urologic and gynecologic cases identified using a new symptom questionnaire and intravesical potassium sensitivity.

OBJECTIVES: Most individuals with interstitial cystitis (IC) have both pelvic pain and urinary urgency/frequency, and many have dyspareunia. Existing questionnaires designed to assess bladder-origin pelvic pain (IC) give little attention to pelvic pain or dyspareunia, however. On the basis of our clinical experience with more than 5000 patients with IC, we have designed a pelvic pain and urgency/frequency (PUF) symptom scale that gives balanced attention to urinary urgency/frequency, pelvic pain, and symptoms associated with sexual intercourse.

METHODS: We used the intravesical potassium sensitivity test (PST) to validate the PUF scale in urologic patients suspected of having IC, gynecologic patients with pelvic pain, controls, and women attending lectures given by one of us (C.L.P.). Positive potassium sensitivity is known to be associated with a bladder epithelial dysfunction present in most individuals with IC.

RESULTS: The PST was positive in 74% of patients with a PUF score of 10 to 14, 76% of those scoring 15 to 19, and 91% of those scoring 20 or higher. All controls' PUF scores were less than 3, and the rate of positive PST in controls was 0%. The PUF scores in women screened at lectures suggested that 1 in 4.5 women have IC.

CONCLUSIONS: High PUF scores appear to correlate directly with a higher likelihood of positive PST in both urologic patients suspected of having IC and gynecologic patients with pelvic pain. The PUF appears to be a valid tool for detecting IC in these two populations, as well as in the general population. Use of the PUF alone may prove to be an accurate method for detecting IC. The IC prevalence may be as high as 1 in 4.5 women.