Brief Answer: Diagnosis as suggested may help to get the peoblem Detailed Answer: Hi. IT is good that you do not have any Medical history other than the present complaints. To recapitulate your problem: feeling of a rock underneath left side ribs which move to right along with bloating, gas, upper back-pain, lasts for a week and fatigue on flare-ups, tests done so far negative. Few questions for you: Do you have constipation? Do you have any other symptoms which you feel may or may not be associated with the present complaints? Any nausea, vomiting, loose notions or altered bowel habits ( constipation alternating with loose motions)? Any anxiety issue, problems at family or at work? From Your History I would confer a Few things::: This may be due to a loaded large bowel- the transverse part of colon with hard feces. When the bowel wants to push it further there is contraction and this may be perceived by you as the feeling of moving rock. The loaded bowel can give you bloating as the gas usually rebounds back and gives back-pressure to give you the present problem. This in turn can give you a reflex back-ache. As the condition affects both the abdomen and the back, fatigue is evident and natural. He flare-up can be due to re-occurrence of the problem which gives the vicious cycle as I explained, body taking time to take care by itself is a matter of a week every time. The endoscopy is not indicated in such cases nor the ultrasonography helps. Colonoscopy definitely has a role in a proper diagnosis, but as you know one has to prepare the bowel by taking the the bowel clearing preparation so no colonoscopy can detect this problem and hence not an investigation of choice. I would suggest you to undergo a proper clinical examination by a Gastroenterologist'' AT THE TIME OF AN ATTACK'' and not during the calm period. At the same time without starting any treatment a proper CT Scan evaluation of the abdomen WITHOUT any preparation can only find this cause. Taking regular laxative, high fiber diet, plenty of oral fluids, Avoiding food that cause constipation or this problem (if you detected so far) may give you a permanent relief. A repeat Colonoscopy as a last review test to rule out mass can be done as a precaution as I do not know when was the investigations were done. I hope this helps you and as this is not a very common finding , it is difficult for the GP to know this type of a problem.

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