Crohn's disease (also known as granulomatous colitis and regional enteritis) is an inflammatory disease of the intestines that may affect any part of the gastrointestinal tract from anus to mouth, causing a wide variety of symptoms. It primarily causes abdominal pain, diarrhea (which may be bloody), vomiting, or weight loss, but may also cause complications outside of the gastrointestinal tract such as skin rashes, arthritis and inflammation of the eye.
Crohn's disease is an autoimmune disease, in which the body's immune system attacks the gastrointestinal tract, causing inflammation; it is classified as a type of inflammatory bowel disease. There has been evidence of a genetic link to Crohn's disease, putting individuals with siblings afflicted with the disease at higher risk. It is understood to have a large environmental component as evidenced by the higher number of cases in western industrialized nations. Males and females are equally affected. Smokers are three times more likely to develop Crohn's disease. Crohn's disease affects between 400,000 and 600,000 people in North America. Prevalence estimates for Northern Europe have ranged from 27–48 per 100,000. Crohn's disease tends to present initially in the teens and twenties, with another peak incidence in the fifties to seventies, although the disease can occur at any age.
There is no known pharmaceutical or surgical cure for Crohn's disease. Treatment options are restricted to controlling symptoms, maintaining remission and preventing relapse.
The disease was independently described in 1904 by Polish surgeon Antoni Leśniowski and in 1932 by American gastroenterologist Burrill Bernard Crohn, for whom the disease was named. Crohn, along with two colleagues, described a series of patients with inflammation of the terminal ileum, the area most commonly affected by the illness. For this reason, the disease has also been called regional ileitis or regional enteritis.