Definition

Ulcerative colitis (pronounced UHL-suh-RATE-ihv kuh-LY-tiss) is an inflammation of the large intestine that causes swelling, ulcerations (open sores), and loss of function in the large intestine.

Description

Ulcerative colitis is a form of inflammatory bowel disease (IBD). The term inflammatory bowel disease refers to a large group of disorders that affect the gastrointestinal (pronounced gas-troh-ihn-TESS-tuh-nuhl) system. Also known as the digestive system, the gastrointestinal (GI) system includes the stomach, small intestine, and large intestine.

Inflammation is a process that occurs when the body's immune system begins to fight off foreign invaders, such as viruses, bacteria, and fungi. The immune system is a network of organs, tissues, cells, and chemicals designed to kill invading organisms. Some of the chemicals produced by the immune system irritate the body's own tissues. They cause heat, redness, swelling, and loss of function. These changes are all characteristic of inflamed tissue...