Crohn's disease is a chronic inflammation of the bowel. Crohn's disease affects both sexes equally and has a seasonal variation. The most common symptom is abdominal pain and weight loss.
Crohn's disease can affect any area from the mouth to the rectum. The other common inflammatory condition of the bowel is ulcerative colitis, which can be very difficult to distinguish from Crohn’s disease. As the name implies, ulcerative colitis only affects the colon.
Crohn's disease affects both sexes equally. The incidence in the Western world varies between two and six per 100 000, but seems to be increasing. This might be because of better awareness of the diagnosis and better diagnostic facilities.
There is a trend for the frequency to increase with greater distance from the equator.
The disease is much less common in Asia, Africa and South America. An interesting finding is a five-fold relative risk in patients of Jewish origin.
There seems to be a seasonal variation in the onset of Crohn's disease, with peak times being autumn and early winter.
Reviewed by Dr Ismail Moola MBCHB (UCT) FCP (SA) Cert Gastro Phys (SA) Specialist Physician / Gastroenterologist Netcare Sunninghill Hospital and part time Lecturer Department of Internal Medicine, Division of Gastroenterology, Wits University. (February 2015)
Previously reviewed by Prof Don du Toit (M.B.Ch.B) (D.Phil.) (Ph.D) (FCS) (FRCS)