Definition of Ulcerative colitis:

Ulcerative colitis is a type of inflammatory bowel disease that affects the large intestine and rectum.

Causes, incidence, and risk factors:

The cause of ulcerative colitis is unknown. It may affect any age group, although there are peaks at ages 15 - 30 and then again at ages 50 - 70.

The disease usually begins in the rectal area and may eventually extend through the entire large intestine. Repeated swelling (inflammation) leads to thickening of the wall of the intestine and rectum with scar tissue. Death of colon tissue or sepsis may occur with severe disease.

The symptoms vary in severity and may start slowly or suddenly. Many factors can lead to attacks, including respiratory infections or physical stress.

Risk factors include a family history of ulcerative colitis, or Jewish ancestry. The incidence is 10 to 15 out of 100,000 people.