Tests and diagnosis

By Mayo Clinic Staff

A complete medical history and physical examination can help determine whether other conditions may be contributing to your diarrhea, including:

  • Celiac disease
  • Autoimmune disorders, such as rheumatoid arthritis

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.
Jan. 30, 2013