Interstitial Cystitis [2]
CAUSES
The cause of interstitial cystitis is unknown, though several theories have been put forward (these include autoimmune, neurologic, allergic and genetic).[4] Regardless of the origin, it is clear that the majority of IC patients struggle with a damaged urothelium, aka bladder lining. When the surface GAG layer is damaged (perhaps via a UTI, excessive consumption of coffees or sodas, traumatic injury, etc.), urinary chemicals can "leak" into surrounding tissues causing pain, inflammation and urinary symptoms. Oral medications like Elmiron and medications which are placed directly into the bladder via a catheter work to repair and hopefully rebuild this damaged/wounded lining, allowing for a reduction in symptoms.
Recent work by the University of Maryland, Baltimore indicates that genetics may be a factor in a small subset of patients. Two genes, FZD8 and PAND, are associated with the syndrome. FZD8, at gene map locus 10p11.2, is associated with an antiproliferative factor secreted by the bladders of IC patients which "profoundly inhibits bladder cell proliferation," thus causing the missing bladder lining.[5] PAND, at gene map locus 13q22-q32, is associated with a constellation of disorders (a "pleiotropic syndrome") including IC and other bladder and kidney problems, thyroid diseases, serious headaches/migraines, panic disorder, and mitral valve prolapse.
SYMPTOMS
It may well be that the symptoms of interstitial cystitis have multiple causes, and IC is actually several syndromes which will eventually be discerned. For example, patients with Hunner's Ulcers are believed to be the most advanced cases. They have larger "wounds", believed to be larger areas of bladder wall thinning, that can be much more difficult to treat. Some researchers believe that patients with Hunner's Ulcers may have an entirely different condition. It is estimated that only 5 to 10% of patients have these ulcers.[6] Far more patients may experience a very mild form of IC, in which they have no visible wounds in their bladder, yet struggle with symptoms of frequency, urgency and/or pain. Still other patients may have discomfort only in their urethra, while others struggle with pain in the entire pelvis. Some patients may experience pelvic floor tightness and dysfunction, while others have normal muscle tone.
Often the symptoms of IC are misdiagnosed as a "common" bladder infection (cystitis), however unlike cystitis, IC has not been conclusively proven to be a bacterial infection and the mis-prescribed treatment of antibiotics is ineffective. The symptoms of IC may also initially be attributed to prostatitis and epididymitis (in men) and endometriosis and uterine fibroids (in women).