What Is Crohn's Disease? What Causes Crohn's Disease?

Crohn's disease is an ongoing condition that causes inflammation of the digestive tract, or the GI (gastrointestinal) tract (the gut). Crohn's disease may also be called ileitis or enteritis. Crohn's disease can affect any part of the gut, from the mouth all the way down to the anus. In the majority of cases the lower part of the small intestine - the ileum - is affected. Patients with Crohn's disease can feel pain; the condition makes the intestines empty frequently, resulting in diarrhea.

In the UK about 1 in 1,500 people have Crohn's disease, according to the National Health Service (NHS), (another study says 1 in 800). It is slightly more prevalent among women than men according to UK sources (NHS), while US sources state that it affects both sexes equally (NIH). Although Crohn's disease typically starts between the ages of 15 to 40, it can start at any age.

As the symptoms of Crohn's disease are similar to other disorders, such as IBS (irritable bowel syndrome) and ulcerative colitis, it can be tricky to diagnose initially. While ulcerative colitis causes inflammation and ulcers in the top layer of the lining of the large intestine, all layers of the intestine may be inflamed and with ulcers in Crohn's disease. The Crohn's disease patient's bowels can have normal healthy sections in between the diseased parts.

Approximately one fifth of all people with Crohn's disease have a close relative with some type of inflammatory bowel disease. People of Jewish descent have a higher chance of developing Crohn's disease