Most clinicians with outpatient practices see undiagnosed cases of interstitial cystitis/painful bladder syndrome (IC/PBS). This chronic condition is characterized by pain perceived to be from the urinary bladder, urinary urgency and frequency, and nocturia. As currently diagnosed, the great majority of cases occur in women. Symptoms wax and wane for months or years or possibly even for the patient's lifetime. The spectrum of symptom intensity is broad. The pain can be excruciating, urgency can be distressing, frequency can be up to 60 times per 24 h, and nocturia can be causative of sleep deprivation. These symptoms can be disabling in terms of daily activities, work schedules, and personal relationships; patients with IC/PBS report less life satisfaction than do those with end-stage renal disease. The etiology of IC/PBS is unknown. It is not a new disease, having first been described in the late nineteenth century in a patient with the symptoms described above and a single ulcer visible on cystoscopy (now called Hunner's ulcer after the urologist who first reported it). Over the ensuing decades, it became clear that many patients with similar symptoms had no ulcer. It is now appreciated that ≥10% of patients with IC/PBS have a Hunner's ulcer.
The definition of IC/PBS, its diagnostic features, and even its name continue to evolve. The International Continence Society, a body devoted to studying disorders of the lower urinary tract and pelvic floor, has defined PBS as "the complaint of suprapubic pain related to bladder filling, accompanied by other symptoms such as increased daytime and night-time frequency, in the absence of proven urinary infection or other obvious pathology." In practice, clinicians have interpreted this definition to include any chronic pelvic pain that increases with bladder filling and/or decreases with voiding and that cannot be explained by reference to another identifiable disease.
Many patients with IC/PBS also have other syndromes, such as fibromyalgia, chronic fatigue syndrome, irritable bowel syndrome, vulvodynia, and migraine. These syndromes collectively are known as functional somatic syndromes (FSSs): chronic conditions in which pain and fatigue are prominent features but laboratory tests and histologic findings are normal. Like IC/PBS, the FSSs often are associated with depression and anxiety. The majority of cases affect women, and more than one FSS can affect a single patient. Because of its similar features and comorbidity, IC/PBS sometimes is considered an FSS.
Contemporary population studies of IC/PBS in the United States indicate prevalences of 2–3% among women and 1–2% among men. For decades, it was thought that 90% of IC/PBS cases occurred in women. These prevalence findings, however, have generated research aimed at determining the proportion of men with symptoms usually diagnosed as chronic prostatitis (now known as chronic prostatitis/chronic pelvic pain syndrome) who actually have IC/PBS. Well-designed studies of the incidence of IC/PBS have not been reported.
Among women, the average age at onset of IC/PBS symptoms is the early forties, but the ...