What is interstitial cystitis/painful bladder syndrome (IC/PBS)?
IC/PBS is pelvic pain, pressure, or discomfort related to the bladder, typically associated with urinary urgency and frequency in the absence of infection or other pathology. IC/PBS may also be called bladder pain syndrome (BPS) and chronic pelvic pain (CPP).
Most experts agree IC/PBS is a combination of symptoms rather than a single disease, and IC/PBS may have more than one cause. Researchers continue to study IC/PBS and investigate different subtypes:
- Non-ulcerative IC/PBS: Ninety percent of patients have the non-ulcerative form of IC/PBS. Non-ulcerative IC/PBS presents with pinpoint hemorrhages, also known as glomerulations. However, these are not specific for IC/PBS; any inflammation of the bladder will give you that appearance. There is also no correlation between how many glomerulations you have and how bad your symptoms are.
- Ulcerative IC/PBS: Five to ten percent of IC/PBS patients have the ulcerative form of the disease and present with Hunner's patches or ulcers. Hunner's ulcers may benefit from treatment with laser surgery.
What causes IC/PBS?
The exact cause of IC/PBS remains a mystery, but research has identified a number of different factors that may contribute to the pathogenesis of the condition. Many researchers believe a trigger, caused by one more events, may damage the bladder:
- bladder trauma, including pelvic surgery
- bladder overdistention (anecdotal cases suggest onset after long periods without access to bathroom facilities)
- pelvic floor muscle dysfunction
- autoimmune disorder
- bacterial infection (cystitis)
- primary neurogenic inflammation (hypersensitivity or inflammation of pelvic nerves)
- spinal cord trauma
These triggers are believed to damage the bladder. Researchers speculate that normal repair of the lining of the bladder does not occur in patients who develop IC/PBS. Research indicates that a protein called antiproliferative factor (APF) is produced in the cells of patients with IC/PBS but not in the cells of healthy control subjects. APF inhibits the growth of bladder cells, and the bladder may be unable to repair itself in the presence of APF.
It is thought that defects in the bladder allow urine contents, such as potassium, to leak into the bladder lining, which may lead to mast cell activation and the release of histamine. These events may activate nerves, cause immunogenic and allergic responses, and lead to progressive bladder injury and chronic nerve pain.
What are the symptoms of IC/PBS?
The symptoms of IC/PBS vary from case to case and even in the same individual. People may experience mild discomfort, pressure, tenderness, or intense pain in the bladder and pelvic area. Some or all of these symptoms may be present:
- Frequency: Day and/or night frequency of urination. In early or very mild cases, frequency is sometimes the only symptom. People with severe cases of IC/PBS may urinate as many as 60 times a day, including frequent nighttime urination, also called nocturia.
- Urgency: The sensation of having to urinate immediately, which may also be accompanied by pain, pressure, or spasms.
- Pain: Pain in the lower abdominal, urethral, or vaginal area may change in intensity as the bladder fills with urine or as it empties. Pain is also frequently associated with sexual intercourse. Men with IC/PBS may experience testicular, scrotal and/or perineal pain, and painful ejaculations.
Who gets IC/PBS?
IC/PBS can affect people of any age, race, or sex. It is, however, most commonly found in women. Recent epidemiological data suggest that IC/PBS affects about 1.3 million women, men, and children in the United States, although these figures may significantly underestimate the true prevalence of the condition. Until recently, only 10 percent were thought to be men, but new estimates are as high as 30 percent. IC in men may often be mistaken for chronic prostatitis/chronic pelvic pain syndrome.
How is IC/PBS diagnosed?
Because symptoms are similar to those of other disorders of the bladder and there is no definitive test to identify IC/PBS, doctors must rule out other treatable conditions before considering a diagnosis of IC/PBS. The most common of these diseases in both sexes are urinary tract infections and bladder cancer. In men, common diseases include chronic prostatitis or chronic pelvic pain syndrome. IC/PBS is not associated with any increased risk of developing cancer.
Once other conditions are excluded, patients with characteristic signs and symptoms generally are treated for presumed IC/PBS. In certain circumstances, some clinicians may choose to evaluate further, with cystoscopy with hydrodistention under general anesthesia, urodynamic studies, or lidocaine instillation. The diagnosis of IC/PBS in the general population is based on the:
- presence of pain related to the bladder, usually accompanied by frequency and urgency
- absence of other diseases that could cause the symptoms.
The potassium chloride challenge, or Parsons' test, also has been used for diagnosis. The potassium chloride challenge is no longer widely used in the United States because of low sensitivity and specificity, and because it is a painful test to undergo that also requires invasive urinary catheterization. This test involves instillation of potassium chloride into the bladder; a positive result is pain and reproduction of IC/PBS symptoms. However, the potassium chloride challenge is not specific for IC/PBS and provides a positive result in other disorders. The test also misses up to 25 percent of patients with IC/PBS.
How is IC/PBS treated?
At this time there is no cure for IC/PBS. For most people with IC/PBS, a combination of treatments is the best approach. Finding the optimal individual treatment plan may also require a period of trial and error.
- Diet modification. Many doctors and patients find that alcohol, tomatoes, spices, chocolate, caffeinated and citrus beverages, and high-acid foods can contribute to bladder irritation and inflammation. Some people also note that their symptoms worsen after eating or drinking products containing artificial sweeteners.
- Oral medicines. Pentosan Polysulfate Sodium (Elmiron®) is the only oral medicine FDA-approved specifically for IC/PBS; Elmiron® is thought to work by restoring a damaged, thin, or "leaky" bladder surface. Other medicines used to treat IC/PBS symptoms include antidepressants, antihistamines, and pain relievers.
- Bladder distention. Known as hydrodistention, bladder distention may help improve symptoms. In many cases, the procedure is used as both a diagnostic test and initial therapy. Researchers are not sure why distention helps, but some believe it may increase capacity and interfere with pain signals transmitted by nerves in the bladder. Symptoms may temporarily worsen 4 to 48 hours after distention but should return to predistention levels or improve within 2 to 4 weeks.
- Bladder instillations. Some people with IC benefit from bladder instillations also called bladder cocktails, which are mixtures of medicines instilled directly into the bladder. These medicines help reduce inflammation and provide temporary repair of the bladder lining.
- Physical therapy. Research demonstrates that physical therapy for treating underlying pelvic floor dysfunction in people with IC can yield positive results and provide significant pain relief. Gentle, stretching exercises help relieve symptoms. Working with a physical therapist who understands IC is the key, because Kegel exercises, often recommended to strengthen pelvic muscles, can worsen IC pain.
- Bladder retraining. People who have found adequate relief from pain may be able to reduce frequency by using bladder retraining techniques. Methods vary, but basically patients decide to urinate (void) and empty their bladder at designated times and use relaxation techniques and distractions to keep to the schedule. Gradually, they try to lengthen the time between scheduled voids. A diary in which to record voiding times is helpful in keeping track of progress.
- Over-the-counter products. Many types of over-the-counter (OTC) products can be helpful in relieving symptoms. Local pharmacies and supermarkets sell most. Some are only sold on the Internet. However, when you have IC/PBS there are many factors to consider before trying one of these products. Talk with your healthcare provider and your pharmacist. Find out if these products are right for you.
- Electrical nerve stimulation. Neuromodulators, small surgically implanted devices, send mild electrical pulses to nerves in the lower back and help manage urinary function and relieve IC symptoms. Nonsurgical external devices are also available.
- Surgery. Hunner's ulcers (or patches), present in 5 to 10 percent of IC/PBS patients, have been successfully treated with laser surgery. Otherwise bladder surgery is considered only as a last resort. Several types of surgeries have been used to treat IC/PBS, including bladder augmentation, urinary diversion, and construction of an internal pouch.
What conditions can overlap with IC/PBS?
Certain related conditions, many of which have an immunologic or allergic basis, occur more commonly in patients with IC/PBS than in the general population, including: