(See also Overview of Voiding Overview of Voiding Voiding disorders affect urine storage or release because both are controlled by the same neural and urinary tract mechanisms. The result is incontinence or retention. For normal urinary function... read more .)
Incidence of interstitial cystitis is unknown, but the disorder appears to be more common than once thought and may underlie other clinical syndromes (eg, chronic pelvic pain). White people are more susceptible, and 90% of cases occur in women.
Cause is unknown, but pathophysiology may involve loss of protective urothelial mucin, with penetration of urinary potassium and other substances into the bladder wall, activation of sensory nerves, and smooth muscle damage. Mast cells may mediate the process, but their role is unclear.
Symptoms and Signs
Interstitial cystitis is initially asymptomatic, but symptoms appear and worsen over years as the bladder wall is damaged. Suprapubic and pelvic pressure or pain occurs, usually with urinary frequency Urinary Frequency Urinary frequency is the need to urinate many times during the day, at night (nocturia), or both but in normal or less-than-normal volumes. Frequency may be accompanied by a sensation of an... read more (up to 60 times/day) or urgency. These symptoms worsen as the bladder fills and diminish when patients void; in some people, symptoms worsen during ovulation, menstruation, seasonal allergies, physical or emotional stress, or sexual intercourse. Foods with high potassium content (eg, citrus fruits, chocolate, caffeinated drinks, tomatoes) may cause exacerbations. Tobacco, alcohol, and spicy foods may worsen symptoms. If the bladder wall becomes scarred, bladder compliance and capacity decrease, causing or worsening urinary urgency and frequency.
Cystoscopy with possible biopsy
Diagnosis is suggested by symptoms after testing has excluded more common disorders that cause similar symptoms (eg, urinary tract infections Introduction to Urinary Tract Infections (UTIs) Urinary tract infections (UTIs) can be divided into upper tract infections, which involve the kidneys (pyelonephritis), and lower tract infections, which involve the bladder (cystitis), urethra... read more , pelvic inflammatory disease Pelvic Inflammatory Disease (PID) Pelvic inflammatory disease (PID) is a polymicrobial infection of the upper female genital tract: the cervix, uterus, fallopian tubes, and ovaries; abscess may occur. PID may be sexually transmitted... read more , chronic prostatitis Prostatitis Prostatitis refers to a disparate group of prostate disorders that manifests with a combination of predominantly irritative or obstructive urinary symptoms and perineal pain. Some cases result... read more or prostatodynia, diverticulitis Colonic Diverticulitis Diverticulitis is inflammation with or without infection of a diverticulum, which can result in phlegmon of the bowel wall, peritonitis, perforation, fistula, or abscess. The primary symptom... read more ).
Cystoscopy Cystoscopy Cystoscopy is insertion of a rigid or flexible fiberoptic instrument into the bladder. Indications include the following: Helping diagnose urologic disorders (eg, bladder tumors, calculi in... read more is necessary and sometimes reveals benign bladder (Hunner) ulcers; biopsy Biopsy of the Kidneys, Bladder, and Prostate Biopsy of the urinary tract requires a trained specialist (nephrologist, urologist, or interventional radiologist). Indications for diagnostic biopsy include unexplained nephritic or nephrotic... read more is required to exclude bladder cancer Bladder Cancer Bladder cancer is usually transitional cell (urothelial) carcinoma. Patients usually present with hematuria (most commonly) or irritative voiding symptoms such as frequency and/or urgency; later... read more . Assessment of symptoms with a standardized symptom scale or during intravesical potassium chloride infusion (potassium sensitivity testing) may improve diagnostic accuracy but is not yet routine practice.
Drugs (eg, pentosan polysulfate sodium, tricyclic antidepressants, nonsteroidal anti-inflammatory drugs [NSAIDs], dimethyl sulfoxide instillation)
Surgery as a last resort
Up to 90% of patients improve with treatment, but cure is rare. Treatment should involve encouraging awareness and avoidance of potential triggers, such as tobacco, alcohol, foods with high potassium content, and spicy foods.
Choice of treatment
In addition to lifestyle modification, bladder training, drugs, intravesical therapies, and surgery are used as needed. Stress reduction and biofeedback Biofeedback For biofeedback, a type of mind-body medicine, electronic devices are used to provide information to patients about biologic functions (eg, heart rate, blood pressure, muscle activity, skin... read more (to strenghten pelvic floor muscles, eg, with Kegel exercises) may help. No treatment has been proved effective, but a combination of ≥ 2 nonsurgical treatments is recommended before surgery is considered.
The most commonly used drug is pentosan polysulfate sodium, a heparin-like molecule similar to urothelial glycosaminoglycan; doses of 100 mg orally 3 times a day may help restore the bladder’s protective surface lining. Improvement may not be noticed for 2 to 4 months. Intravesical instillation of 15 mL of a solution containing 100 mg of pentosan or 40,000 units of heparin plus 80 mg of lidocaine and 3 mL of sodium bicarbonate may benefit patients unresponsive to oral drugs. Tricyclic antidepressants (eg, imipramine 25 to 50 mg orally once a day) and NSAIDs in standard doses may relieve pain. Antihistamines (eg, hydroxyzine 10 to 50 mg once before bedtime) may help by directly inhibiting mast cells or by blocking allergic triggers.
Dimethyl sulfoxide instilled into the bladder through a catheter and retained for 15 minutes may deplete substance P and trigger mast cell granulation; 50 mL every 1 to 2 weeks for 6 to 8 weeks, repeated as needed, relieves symptoms in up to one half of patients. Intravesical instillation of bacille Calmette-Guérin (BCG) and hyaluronic acid are under study.
Surgical and other procedures
Bladder hydrodistention, cystoscopic resection of a Hunner ulcer, and sacral nerve root (S3) stimulation help some patients.
Surgery (eg, partial cystectomy, bladder augmentation, neobladder, and urinary diversion) is a last resort for patients with intolerable pain refractory to all other treatments. Outcome is unpredictable; in some patients, symptoms persist.
Interstitial cystitis is noninfectious bladder inflammation that tends to cause chronic pelvic pain and urinary frequency.
Diagnosis requires exclusion of other causes for symptoms (eg, UTIs, pelvic inflammatory disease, chronic prostatitis or prostatodynia, diverticulitis), cystoscopy, and biopsy.
Cure is rare, but up to 90% of patients improve with treatment.
Treatments can include diet modification, bladder training, and drugs (eg, pentosan polysulfate sodium, tricyclic antidepressants, NSAIDs, dimethyl sulfoxide instillation).
Surgery is a last resort for patients with intolerable pain refractory to all other treatments.