What is cause of interstitial cystitis?

No one knows what causes interstitial cystitis, but doctors studying interstitial cystitis believe that it is a real, physical problem. They also say it is not a result, symptom, or sign of an emotional problem. Because the symptoms of interstitial cystitis are varied, most researchers believe that it represents a spectrum of disorders rather than only one single disease. One area of research on the cause of interstitial cystitis has focused on the layer that coats the lining of the bladder. This area is called the glycocalyx and is made up primarily of substances called mucins and glycosaminoglycans. This layer normally protects the bladder wall from toxic effects of the urine and its contents. Researchers have found that this protective layer of the bladder is leaky in about 70% of interstitial cystitis patients. Researches also hypothesized that this may allow substances in urine to pass into the bladder wall where they might trigger interstitial cystitis. Along with altered permeability of the bladder wall, researchers are also examining the possibility that interstitial cystitis results from decreased levels of protective substances found in the bladder wall. Reduced levels of glycosaminoglycans or other protective proteins might also be responsible for the damage to the bladder wall that is seen in interstitial cystitis. No matter what the mechanism for disruption of the bladder lining, potassium is one substance that may be involved in damage to bladder wall. Potassium is present in high concentrations in urine and is normally not toxic to the bladder lining, but if the tissues lining the inside of the bladder are disrupted or are abnormally leaky, potassium could then penetrate the lining tissues. Then it enters the muscle layers of the bladder, where it can cause damage and promote inflammation. Researchers have isolated a substance known as antiproliferative factor that appears to block normal growth of cells that make up lining of bladder. That antiproliferative factor has been identified almost exclusively in the urine of people suffering with interstitial cystitis. Research is underway to clarify the potential role of this factor in development of interstitial cystitis. Increased activation of sensory nerves in the bladder wall is also thought to contribute to the symptoms of interstitial cystitis. Cells known as mast cells, which play a role in the body’s inflammatory response to injury release some specific chemicals. These chemicals are believed to be capable of contributing to the symptoms of interstitial cystitis. Other theories about the cause of interstitial cystitis are that it is a form of autoimmune disorder or that infection with an unidentified organism may be producing the damage to the bladder.