What causes interstitial cystitis?
No one knows what causes interstitial cystitis. In fact, because IC varies from person to person, scientists believe there may be multiple causes, including:
- A defect in the bladder lining that allows harmful substances in the urine to come into contact with the bladder wall
- An overproduction of histamine and other potentially harmful chemicals by mast cells, a special type of cell that normally protects the body from allergic reactions
- Changes in the nerves inside the bladder
- Some type of autoimmune response in which the body attacks its own organs and tissue
The urine of people with IC contains a substance known as antiproliferative-factor or APF. APF appears to block the development of cells in the bladder lining. This leads scientists to think that some people are predisposed to get interstitial cystitis after an injury, such as an infection, to the bladder.
What are the symptoms of interstitial cystitis?
Symptoms of interstitial cystitis vary from individual to individual. Some people may have only a mild sense of urgency while others have multiple symptoms. Any of the following symptoms could indicate the presence of IC:
- Pain ranging from mild to intense in the bladder and surrounding pelvic region and perineum -- the area between the anus and vagina in women and the anus and scrotum in men
- Urgent need to urinate, even if only small amounts of urine are present
- Frequent need to urinate
- Pain that worsens during menstruation in women
- Painful sexual intercourse in women
- Pain or discomfort in the scrotum or penis in men
How does the doctor diagnose interstitial cystitis?
There is no one test that is specific for interstitial cystitis. Because other conditions can cause the same symptoms, a diagnosis is made only after other possible causes are ruled out. Other conditions that can cause the same symptoms include:
- Bladder cancer
- Chronic prostatitis in men
- Kidney stones
- Sexually transmitted disease
- Urinary tract infection
- Vaginal infection
The doctor will start by asking you about your symptoms. Then the doctor will give you a physical exam and ask for a series of tests to rule out other possible causes. Those tests include:
- Urine analysis and urine culture. This involves taking a sample of urine to study in the lab. Red and white blood cells and bacteria in the urine indicate an infection. If the urine is sterile while symptoms persist, the doctor may suspect IC.
- Cystoscopy with bladder distention. With this test, the doctor looks at the inside of your bladder using a cystoscope. That's a hollow tube with a light and lenses that the doctor inserts through the urethra, the tube that urine passes through when you urinate. During the exam, the doctor may fill the bladder with a liquid or gas to distend or stretch it. This allows a better view of the walls and makes it easier to check for abnormalities. Because distension is painful, this procedure is done with some form of anesthesia.
- Biopsy. During the cystoscopy, the doctor may take a small sample of tissue to examine under a microscope to rule out bladder cancer. Having IC does not increase your risk for bladder cancer.