To help diagnose microscopic colitis, your doctor may ask you to have a colonoscopy or sigmoidoscopy. Both procedures use a tube with a camera on it to inspect the colon.
During the procedure, your doctor collects tissue samples that will be checked for signs of microscopic colitis.
Microscopic Colitis Causes
Experts aren't sure what causes microscopic colitis, but bacteria, toxins, or viruses are possible causes. It could also be related to a problem with your immune system. Your body may react to a false threat and start attacking the cells in your own digestive tract.
Some medications can increase your risk for microscopic colitis, including: