Clinical Definition

Ulcerative colitis is a common and chronic gastrointestinal disorder classified as an inflammatory bowel disease (IBD). The other common type of IBD is Crohn’s disease. In IBD, the immune system is thought to have an abnormal response to food, bacteria and other materials in the intestine, mistaking them for foreign substances and attacking intestinal cells. The body then sends white blood cells to the intestines to help the battle, and this produces chronic inflammation.

In Our Own Words

Ulcerative colitis and Crohn’s disease are distinct gastrointestinal disorders, but have overlapping signs and symptoms. Both types of diseases are marked by an abnormal response by the immune system. Neither is related to irritable bowel syndrome (IBS), which affects the colon’s muscle contractions but is not marked by inflammation.

During a bout with ulcerative colitis, gastrointestinal inflammation is typically limited to the large bowel, or the colon and rectum. As inflammation persists, the stool may loosen and become bloody. Cramping pain in the abdomen can occur. While many sufferers of  ulcerative colitis have mild symptoms, others have severe signs that come and go between flare-ups. Exactly why ulcerative colitis occurs is not known, but environmental and genetic factors are thought to play a role. Treatments include medication, diet modification and sometimes surgery.