The cause of interstitial cystitis of the bladder in women is unknown, as of 2015, although scientists suspect several causes exist, according to WebMD. Bladder lining defects, nerve changes, autoimmune responses, bladder injuries and excessive histamine production are all hypothesized causes.
Bladder lining defects may result in interstitial cystitis by enabling the bladder wall to have contact with harmful substances found in urine, explains WebMD. Another possibility is that the condition develops as a result of the body attacking itself as an autoimmune response. Laboratory tests show that the urine of individuals with interstitial cystitis contains antiproliferative-factor, a substance that prevents cells from developing in the bladder lining. For this reason, scientists suspect that trauma to the bladder, such as from an infection, may increase one's likelihood of developing the condition.
Interstitial cystitis is a condition characterized by chronic bladder inflammation that primarily affects middle-aged women, notes WebMD. The inflammation produces symptoms such as urinary urgency, urinary frequency, pain in the bladder, perineum and pelvic region, and pain during sexual intercourse. The pain ranges in intensity from mild to severe. Women may notice the pain becoming more intense during menstrual periods. Men with interstitial cystitis may also experience discomfort or pain in the penis and scrotum.