A complete medical history and physical examination can help determine whether other conditions may be contributing to your diarrhea, including:
Your doctor will ask about any medications you are taking, particularly aspirin and ibuprofen, which may increase your risk of microscopic colitis.
Tests used to diagnose microscopic colitis may include:
- Stool sample analysis to help rule out infection as the cause of persistent diarrhea.
- Blood test or upper endoscopy with biopsy to rule out celiac disease. In endoscopy, a long, thin tube with a camera on the end is used to examine the upper part of your digestive tract. A tissue sample (biopsy) may be removed for analysis in the laboratory.
- Colonoscopy or flexible sigmoidoscopy with biopsy to help rule out other intestinal disorders. Both tests use a long, thin tube with a camera on the end to examine the inside of your colon. The colons of people with microscopic colitis appear normal. A biopsy can be obtained during colonoscopy or flexible sigmoidoscopy and analyzed for signs of microscopic colitis.