Causes

The exact cause of interstitial cystitis/bladder pain syndrome (IC/BPS) remains a mystery, but researchers have identified a number of different factors that may contribute to the development of the condition. Many researchers believe a trigger (caused by one more events) may initially damage the bladder or bladder lining, and ultimately lead to the development of IC/BPS. Some of these triggers may be:

• Bladder trauma (such as from 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

It is thought that this damage to the bladder wall then allows particles in the urine, such as potassium, to leak into the bladder lining. Once these particles get into the bladder lining, they can lead to a variety of body responses that may further damage the bladder and cause chronic nerve pain.

Researchers speculate that one reason for this continued damage to the bladder is that normal repair of the lining of the bladder does not occur in patients who develop IC. Research indicates that this might be due to a protein called antiproliferative factor (APF). Studies have shown that APF is produced by the cells of patients with IC, but not by the cells of healthy people. APF prevents the growth of bladder cells and the bladder may be unable to repair itself when APF is present.

In recent years the relationship between IC and abuse (sexual, physical, and childhood sexual) has become a hotly debated topic. The results of IC and abuse studies have varied greatly, indicating no connection, a slight connection, and a fairly high rate of incidence among those with IC. Many studies have also indicated that the rate of abuse for people with IC is the same as the rate in the general population. Finding a definitive answer to the abuse question may lie in using longitudinal studies which would follow a large group IC patients and controls over several years. However, several researchers and clinicians believe that since there has been only modest data supporting the abuse theory, clinicians and researchers may be losing sight of their main goal—providing real help to those with IC—by focusing on this issue.