What causes IC?
Some of the symptoms of IC / PBS resemble those of bacterial infection, but medical tests reveal no organisms in the urine of patients with IC / PBS. Furthermore, patients with IC / PBS do not respond to antibiotic therapy. Researchers are working to understand the causes of IC / PBS and to find effective treatments. In recent years, researchers have isolated a substance found almost exclusively in the urine of people with interstitial cystitis. They have named the substance antiproliferative factor, or APF, because it appears to block the normal growth of the cells that line the inside wall of the bladder.