Current investigations and treatment of interstitial cystitis.

Interstitial cystitis (IC) is a chronic condition characterized by a constellation of symptoms such as urinary frequency, nocturia, urinary urgency, suprapubic pressure, and bladder and pelvic pain. Since its original description, the etiology of the disorder has remained unknown despite intense investigations. The International Cystitis Association (ICA) and the National Institutes of Arthritis, Diabetes, Digestive and Kidney Diseases (NIDDK) have been instrumental in supporting the United States Interstitial Database (ICDB) and foster research to study the disorder. The NIDDK developed criteria to ensure that all groups of patients treated would be relatively comparable. However, many patients who would be clinically considered to have IC do not fulfill all the NIDDK criteria. Many clinical criteria for the diagnosis of IC, such as the presence of glomerulations and the intravesical potassium chloride test, are being challenged. The epidemiology of the disorder is not well established, but there are an estimated 700,000 cases of IC in the United States. Numerous pathophysiologic mechanisms have been proposed, but none have been proven. There is no representative animal model of IC. Both the oral and intravesical treatments of IC are noncurative, and few are based on a plausible mechanism or scientific evidence. Surgical treatment should be considered with extreme caution; it is the last therapeutic option because failure rate can be substantial.