How is inflammatory bowel disease diagnosed?

Crohn’s disease and ulcerative colitis have very similar symptoms, so it can be difficult to tell which one the patient is suffering from.

Tests to diagnose IBD include the following:

  • CT Enterography: A test that allows the doctor to perform an X-ray examination of the entire abdomen. Findings of active disease include thickened bowel wall, inflamed bowel, narrowed areas, and fistulas.
  • Flexible sigmoidoscopy: A test that provides a view of the lowest two feet of the colon. The doctor inserts a slender, flexible, lighted tube through the rectum and examines this section of the colon, looking for inflammation, ulcers, or other problems.
  • Colonoscopy: The doctor inserts a thin, flexible, lighted tube that is long enough to view the entire colon with the attached camera. The doctor also can take tissue samples from inside the colon that can be tested in the laboratory for clusters of inflamed cells called granulomas. These clusters are present in Crohn’s disease but not in ulcerative colitis, so this is a very useful test for telling the difference between the two diseases.

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