I'm a 24 year old male, 5'10'', about 165. Over the years, I've had bouts of rectal bleeding, or blood in my stool, usually once, occasionally twice a month, and only for about 2 days at a time. In high school when it started, I got a colonoscopy, which came back 100% clean, no polyps, no tears, no problems. A year or so later, after it persisted, I got another colonoscopy which also came up clear, as well as a series of other tests on my GI tract, and tests for Chron's disease and other conditions, all of which came back negative. None of the several doctors I consulted could figure out the cause of the bleeding. Additionally, it's not simple anal fissure; there's no pain or tearing around the anus associated with it when it happens. I made some dietary changes which seemed to help for the past few years, including cutting down on dairy, eating a high fiber diet, drinking more water and staying better hydrated, and going vegetarian with the exception of seafood. These changes reduced my bleeding to about once every other month, until this week. This week, I've bled consistently for the last 5 days. As always, the blood is light colored and liquid, not dark or clotted that I can tell. I am concerned, of course, but so disheartened by the lack of results in the last round of testing I underwent, that I don't want to waste the time and the money to go through all that again unless I have some possible new leads to pursue that haven't already been tested, re-tested, and excluded in vain. Is there any possible explanation or advice you might be able to offer for my situation?