Interstitial cystitis (IC) is a chronic, often debilitating, bladder condition. Its symptoms are urinary urgency, frequent urination and/or pain anywhere between the navel and the inner thighs, front or back. The symptoms can be mild or severe, and intermittent to constant. The more severe cases of IC can have a devastating effect on the patient and their loved ones. Often, diagnostic tests reveal no apparent abnormalities, and IC patients and their physicians can experience frustration with recurring symptoms. Not all patients with urgency, frequency, and pain have IC, and urologists can help make the diagnosis and manage the symptoms.
How does the urinary tract function under normal conditions?
After urine is made in the kidneys, it flows down the ureters into the bladder. The bladder is a hollow, balloon-like organ with muscular walls. As the bladder fills, the muscle relaxes so that the bladder expands and holds urine. During urination, the bladder muscle contracts to squeeze out the urine. The urethra is the tube through which urine passes from the bladder to the outside. The urethra has a muscle, the sphincter, which is completely different from the bladder muscle. The sphincter normally stays closed and makes a seal to keep urine from leaking. During urination, the sphincter opens and lets urine pass. The bladder and urethra have a specialized lining called the epithelium. The epithelium forms a barrier between the urine and the bladder muscle. The epithelium also helps to keep bacteria from sticking to the bladder, so it helps to prevent bladder infections.
What is interstitial cystitis (IC)?
IC is thought to be a chronic inflammatory condition of the bladder that may also affect the urethra and the prostate. Its symptoms may be mild or severe, occasional or constant. It is not an infection, but its symptoms can feel like those of a bladder infection.
What are some risk factors for IC?
There are no specific behaviors or exposures (such as smoking) known to increase a person's risk for getting IC. Symptoms may be triggered by a a bladder infection, and often symptoms can persist even after the infection is treated. The tendency to get IC may be influenced by a person's genes, and so having a blood relative with IC may increase the risk of getting IC yourself. About 90 percent of people diagnosed with IC are women,which suggests that being female may increase the risk of getting IC. However, the difference in rates of IC for men vs. women may not really be as high as we think, because some men diagnosed with "prostatitis" or similar conditions with different labels may really have IC.
What causes IC?
The causes of IC are being studied in medical centers around the world. Many researchers believe that IC is caused by one or more of the following: (1) a defect in the bladder epithelium that allows irritating substances in the urine to penetrate into the bladder; (2) a specific type of inflammatory cell (mast cell) releasing histamine and other chemicals that promote IC symptoms in the bladder; (3) there is something in the urine that damages the bladder; (4) the nerves that carry bladder sensations are changed, so pain is now caused by events that are not normally painful (such as bladder filling); and/or (5) the body's immune system attacks the bladder, similar to other autoimmune conditions. It is likely that different processes occur in different groups of IC patients. It also is likely that these different processes may affect each other (for example, a defect in the bladder epithelium may promote inflammation and stimulate mast cells). Recent research shows that IC patients may have a substance in the urine that inhibits the growth of cells in the bladder epithelium. Therefore, some people may be predisposed to get IC after an injury to the bladder such as an infection.
What are symptoms of IC?
Different IC patients may experience different symptoms. Patients with IC usually have urinary frequency/urgency or pain or both. Many people have only pain and no frequency, but most IC patients have all of the symptoms. There have been many reported cases when a person diagnosed with IC was not experiencing substantial pain.
Frequency is the need to urinate more often than normal. Normally, the average person urinates no more than seven times a day, and does not have to get up at night to use the bathroom. An IC patient often has to urinate frequently both day and night. As frequency becomes more severe, it leads to urgency. Urgency to urinate is a common IC symptom. Some patients feel a constant urge that never goes away, even right after urinating. While others with IC urinate often, they do not necessarily feel the urge to go all the time.
IC patients may have bladder pain that gets worse as the bladder fills. Some IC patients feel the pain in other areas besides the bladder. A person may feel pain in the urethra, lower abdomen, lower back, or the pelvic or perineal area. Women may experience pain in the vulva or the vagina and men may feel the pain in the scrotum, testicle, or penis. The pain may be constant or intermittent.
Many IC patients can identify certain things that make their symptoms worse. For example, some people's symptoms are made worse by certain foods or drinks. Many patients find that symptoms are worse if they have stress (either physical or mental stress). The symptoms may vary with the menstrual cycle. Both men and women with IC can experience sexual difficulties due to this condition; women may have pain during intercourse because the bladder is right in front of the vagina, and men may have painful orgasm or pain the next day.
How is IC diagnosed?
At this time, doctors have different opinions about how to diagnose IC. This is because no test so far has turned out to be completely accurate. All doctors do agree that a medical history, physical exam and urine tests are needed for evaluation. These tests are important to rule out other conditions that might be causing the symptoms. Some doctors believe that IC is present if a patient has IC symptoms and no other cause for those symptoms can be found. Other doctors believe that more tests are necessary to determine whether the patient has IC.
One test that many doctors use is simple office cystoscopy, in which the doctor looks inside the bladder with a cystoscope while the patient is not under anesthesia. This test can rule out other problems such as cancer. Whereas simple cystocopy can be performed in the doctor's office, a more invasive test can be performed in the operating room. This involves a basic cystoscopic examination followed by a stretching or distention of the bladder by instilling water under pressure. This can reveal cracks in the bladder in more severe cases.
Cystoscopy was once part of the standard IC evaluation, but it is no longer always considered a necessary test for IC because the examination is usually normal. However, during cystoscopy, some IC patients will have small areas of bleeding, or actual ulcers, which the doctor can see through the cystoscope. The ulcers are usually found only in patients who are over the age of 60 years and can often be suspected by the presence of blood in the urine. If a person has symptoms of IC and the cystoscopy shows bleeding or ulcers, the diagnosis is fairly certain. Most people who have IC symptoms do not have these bleeding areas, but they may really have IC after all and may respond to the same treatments. The doctor will often then perform a bladder biopsy, which helps to rule out other bladder diseases. While this procedure is primarily used for testing, some IC patients may experience relief of symptoms afterwards. Some doctors believe that if a person has the typical symptoms of IC, and no other cause for the symptoms is found, then the patient has IC. This is still an area of controversy, and future research may help to resolve it.
Urodynamics evaluation is another test that was once considered to be part of the standard IC evaluation, but may not be necessary in all cases. Urodynamics is particularly useful when urinary symptoms are particularly bothersome or do not respond as expected to prescribed treatments. This test involves filling the bladder with water through a small catheter, and measuring bladder pressures as the bladder fills and empties. The usual results with IC are that the bladder has a small capacity and perhaps pain with filling.
Some doctors use a test called the potassium sensitivity test, in which potassium solution and water are placed into the bladder one at a time, and pain/urgency scores are compared. A person who has IC feels more pain/urgency with the potassium solution than with the water, but patients with normal bladders cannot tell the difference between the two solutions.
At this time, there is no definite answer about the best way to diagnose IC. However, if a patient has typical symptoms and a negative urine examination showing no infection or blood, then IC should be suspected.
How is IC treated?
The most successful treatments for IC involve a "multimodal" approach. This may involve dietary and behavioral changes, medications, physical therapy, and occasionally minimally invasive therapies. Treatments are focused around improving symptoms and preventing relapses. Individualized treatment is tailored by the urologist and patient working as a team.