Tixbut,
Have you ever had an MRI of your abdomen? What tests have the doctors preformed?
I have UC and had to deal with a similar situation for over 10 years. I had intermittent episodes of abdominal pain, that at first I thought were associated with my UC. I had every test under the sun more than once through out the years. I was even scheduled for abdominal surgery on 3 separate occasions, but each time the surgeons cancelled the procedure when they didn't know what was wrong or what organ what to remove.
My physicians would constantly tell me either my UC was in remission or that I had relatively minor inflammation and that I should not be experiencing abdominal pain with the severity that I was describing. Like you, I was given a diagnosis of IBS as well, but that diagnosis was meaningless because it did nothing to address my abdominal pain.
Several years later, after I was hospitalized for 5 days with the most gut wrenching abdominal pain that I ever remember experiencing, I got fed up with everyone telling me that the pain I was wasn't there, or that it was due to anxiety and all in my head. I had started keeping a journal of everything I ate, along my daily activities and also recorded when I experienced any symptoms, whether I thought they were related or not. Turns out that after a few months of keeping that journal I discovered that it was porphyria that was complicating the problem in my case, not IBS. For me, keeping that journal was very useful for identifying what was actually going on.
I am not suggesting that Porphyria is causing your symptoms, in fact it should be near the bottom of the list since it is a very rare disorder. However, doing something as simple as keeping a journal may point you or your doctors in the right direction for a proper diagnosis.
The list of differential diagnosis for abdominal pain is pretty wide. So if you record relevant events you may be able to rule one diagnosis out over another and may even find subtleties that could help point you in the right direction. For example you might want to write down if the pain localized to one part of your abdomen or if it moves around, if you experiencing diarrhea or constipation or both. How severe is the pain? Does the pain ever get so severe that it wakes you up while you are sleeping? Also, keeping tracking of when you are having the most severe symptoms in your log with respect to your menstrual cycle may be particularly useful. Sometimes stress can be a precipitating factor for abdominal pain so you may want to note when or if you are experiencing a lot of stress in your log as well. Note any inconsistencies. In other words, try record your daily activities along with any symptoms you may have, particularly if you experience any symptoms that you think might not be related.
I think that keeping a journal is an invaluable tool for establishing patterns and/or identifying relevant subtleties which may help to significantly narrow the differential diagnosis window.
Good luck, and keep us posted I hope you get some relief soon!
