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Inflammatory Bowel Disease

Inflammatory Bowel Disease Overview

The term inflammatory bowel disease (IBD) describes a group of disorders in which the intestines become inflamed. What causes them to become red and swollen is not known. The most likely cause is an immune reaction the body has against its own intestinal tissue.

Two major types of IBD are ulcerative colitis and Crohn's disease. Ulcerative colitis is limited to the colon or large intestine. Crohn's disease, on the other hand, can involve any part of the gastrointestinal tract from the mouth to the anus. Most commonly, though, it affects the small intestine or the colon or both.

If you have an IBD, you know it usually runs a waxing and waning course. When there is severe inflammation, the disease is considered active and the person experiences a flare-up of symptoms. When there is less or no inflammation, the person usually is without symptoms and the disease is said to be in remission.

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What Causes Inflammatory Bowel Disease?

IBD is an idiopathic disease -- a disease with an unknown cause. Some agent or a combination of agents triggers the body's immune system to produce an inflammatory reaction in the intestinal tract. It could be an infectious agent such as bacteria or viruses or an antigen such as a protein from cow milk. It could also be that the body's own tissue causes an autoimmune response. Whatever causes it, the reaction continues without control and damages the intestinal wall, leading to bloody diarrhea and abdominal pain.

What are the Symptoms of Inflammatory Bowel Disease?

IBD is chronic, which means it lasts a long time. As with other chronic diseases, a person with IBD will go through periods in which the disease flares up and causes symptoms followed by periods in which symptoms decrease or disappear and good health returns. Symptoms range from mild to severe and generally depend upon what part of the intestinal tract is involved. They include:

abdominal cramps and pain
bloody diarrhea
severe urgency to have a bowel movement
fever
weight loss
loss of appetite
iron deficiency anemia due to blood loss

Are There Complications Associated With IBD?

IBD can lead to several serious complications in the intestines, including:

profuse intestinal bleeding from the ulcers
perforation, or rupture of the bowel
narrowing – called a stricture -- and obstruction of the bowel
fistulae (abnormal passages) and perianal disease, which is disease in the tissue around the anus
toxic megacolon, which is an extreme dilation of the colon that is life-threatening

IBD also increases the risk of colon cancer and can involve organs other than the intestines. Someone with IBD may have arthritis, skin conditions, inflammation of the eye, liver and kidney disorders, or bone loss. Of all the complications outside the intestines, arthritis is the most common. Joint, eye, and skin complications often occur together.