Microscopic Colitis



Important information regarding your health

Microscopic colitis (MC) is inflammation of the bowel that is only visible using a microscope. The term bowel refers to any part of the small or large intestine. Colitis means inflammation of the colon. The large intestine includes the colon and the rectum that together are about five feet long. The small intestine can be 12 to 20 feet long.

MC is less severe than other types of inflammatory bowel disease (IBD) because it does not lead to cancer and rarely requires surgery. However, MC can cause considerable pain and discomfort.

MC has two main forms - collagenous colitis and lymphocytic colitis. The symptoms of and treatment for both are identical. Although it is believed that the two forms may be different presentations of the same disease, they differ in the way intestinal tissue appears when seen with a microscope. In both forms, an increase in white blood cells can be seen within the intestinal epithelium - the layer of cells that lines the intestine. Increased white blood cells are a sign of inflammation. With collagenous colitis, a layer of tissue called collagen appears thicker than normal beneath the epithelium.

MC can affect anyone but is more common in people of age 60 or older.1 Rates of MC are similar to other forms of IBD, affecting about 700,000 people in the U.S..2 Although MC affects both men and women, collagenous colitis is much more common in women. There is a known association between microscopic colitis and celiac disease.

Labellarge Intestines Labellarge Intestines

Common Symptoms:

Chronic, non-bloody, watery diarrhea is the main symptom of MC. Episodes of diarrhea can last for weeks, months, or years. Most cases are interrupted by similarly long periods of remission (i.e. periods when the diarrhea goes away).

Other common symptoms of MC include:

• Abdominal cramps or pain

• Abdominal bloating

• Mild weight loss

• Dehydration

• Nausea

• Weakness


The cause of MC is unknown. However many scientists believe it is an abnormal immune response triggered by something interacting with the gastrointestinal (GI) tract - the large, muscular tube that extends from the mouth to the anus that digests food. Scientists believe one’s genes may make a person more likely to develop MC. Although a gene unique to MC has yet to be found, dozens have been linked to other forms of IBD.

Treatment Option:

People with MC generally achieve relief with treatment, although relapses can occur. Some patients require long-term therapy because they experience prompt relapses when treatment is stopped. Unlike IBD, MC usually does not result in other problems, such as bowel obstruction or colon cancer.

Questions to Ask Your Healthcare Provider:

  • What treatment option is best for me?
  • What are the potential side effects?
  • What dietary or lifestyle changes do you recommend?

For more information:

Crohn’s & Colitis Foundation of America
733 Third Avenue, Suite 510
New York, NY 10017
Phone: 1.800.932.2423/212.685.3440
Fax: 212.779.4098
Email: info@ccfa.org
Internet: www.ccfa.org


Digestive Disease National Coalition
507 Capitol Court NE, Suite 200
Washington, DC 20002
Phone: 202.544.7497 Fax: 202.546.7105
Email: ddnc@hmcw.org
Internet: www.ddnc.org


Gastro-Intestinal Research Foundation
20 W Kinzie Street, 17th Floor
Chicago, IL 60654
Phone: 312.332.1350
Fax: 312.332.4757
Email: info@girf.org Internet: www.girf.org