I agree with the testing thus far. The colonoscopy would exclude most cases of the diarrhea as well as look for possibilities leading to blood in the stool.
I would test the stool for causes of malabsorption, and obtain breath tests to exclude lactose intolerance.
Celiac disease can be considered, and evaluated with the appropriate blood tests.
If the tests remain negative, irritable bowel can be considered - and treated appropriately.
If Crohn's disease continues to be suspected, a small bowel series, or MRI enteroscopy, would be the tests to further evaluate for this.
These options can be discussed with your personal physician.
This answer is not intended as and does not substitute for medical advice - the information presented is for patient education only. Please see your personal physician for further evaluation of your individual case.
Kevin Pho, M.D.
www.kevinmd.com
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