To better understand interstitial cystitis (IC), it's helpful to have some knowledge of the urinary system and what might cause IC. Here's a short overview.
The Urinary System
The urinary system is composed of various organs, tubes, muscles and nerves that work together to create, store and carry urine.
The kidneys produce urine, a fluid containing irritating substances and natural waste products. From each kidney, the urine flows through a long thin tube called the ureter. From the ureters, the urine travels to the bladder.
The Bladder and Its Protective Layer
The bladder is an organ located in the pelvic area. It is a muscular sac responsible for storing and emptying urine. Since the bladder may store urine for several hours, it has a protective lining to shield its wall from the irritating waste products of the kidneys. This protective mucous lining is called the glycosaminoglycans (GAG) layer.
This layer is supposed to act as a barrier to keep the irritating substances of the urine away from the bladder wall and prevent them from leaking out of the bladder into the bloodstream.
Causes of IC
No one is 100% sure of what causes IC. But experts who study IC do have several theories to help explain why some people develop IC and others don't.
Some evidence points to irritating substances in the urine or damage to nerve cells along the bladder wall. Other evidence suggests that IC is caused by the body's own natural defense system turning on itself. Chronic pain in the bladder may also be aggravated by allergies. In some patients, symptoms may get worse when certain foods are eaten. Some experts also believe that the bladder's GAG layer has become thinned or is absent. A damaged GAG layer may allow irritating substances in the urine to aggravate the bladder wall and cause inflammation and pain.
Medical experts believe that many causes could actually be working together, resulting in the same set of painful symptoms common in IC. Fortunately, there's a growing awareness of IC.
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