Crohn's Disease

Crohn's disease is an inflammation of the alimentary canal. Inflammation from the disease can occur anywhere along the canal from the mouth to the anus although it usually starts in the lower part of the small intestine, called the ilium, or in the colon. Its signs and symptoms vary widely among afflicted individuals.

What is Crohn's Disease?

Crohn's disease is an inflammation of the alimentary canal. The alimentary canal includes the mouth, esophagus, stomach, intestines, colon, and rectum. Inflammation from the disease can occur anywhere along the canal from the mouth to the anus. It usually starts in the lower part of the small intestine, called the ilium, or in the colon.

The disease was named after American gastroenterologist Burrill Bernard Crohn (1884–1983), who described its symptoms in 1932 after observing various symptoms in patients all with an inflamed terminal ilium (the portion of the small intestine most distant from the digestive tract).

Classified as a type of inflammatory bowel disease (IBD), Crohn's disease can often be present simultaneously at various locations within the digestive tract. In fact, among its most characteristic features is the presence of inflamed regions of intestine separated by apparently normal regions called skip areas. Another characteristic feature is that the inflammation goes through all layers of the intestinal wall from the innermost mucosal layer through the outermost serosal layer. The intense transmural nature of the inflammation explains the frequent stricture formation in the presence of holes, called fistulae, which pierce the intestinal wall. Because the inflammation can be present at multiple sites, its signs and symptoms vary widely among affected individuals.

What Are the Signs and Symptoms of Crohn's Disease?

The signs and symptoms of Crohn's disease vary widely among individuals, and they may appear abruptly or slowly develop over time. Overall, the primary signs and symptoms are:

When severe cases of Crohn's disease occur, other signs and symptoms can include arthritis, eye inflammation, fatigue, fever, inflammation of a bile duct *

How Is Crohn's Disease Diagnosed?

Especially when abdominal pain, bloody stool, bowel habit changes, diarrhea, and unexplained fever are present, a medical professional should be consulted. The professional, possibly a gastroenterologist (a person specializing in diseases of the digestive system), will likely use one or more of the following tests to identify the problem:

What Are the Causes of Crohn's Disease?

The exact physical cause of Crohn's disease is not known. Medical professionals think that genetic factors have something to do with causing the disease, as is the case with most autoimmune diseases * . About 20 percent of all patients have family members with the disease. Mutations (changes) in specific genes are believed to be the basis of this genetic problem.

Crohn's disease may be caused by a problem with the person's immune system * . Bacteria or viruses may invade the human body and when the immune system tries to counter the germs, the digestive tract becomes inflamed. In another scenario, an abnormally functioning immune system may attack bacteria normally found in the intestines. Such action also causes the digestive tract to become inflamed.

Crohn's disease is not caused by long-term anxiety and stress or any particular diet and eating habits. However, emotional stress and diet are likely to complicate the condition.

How Is Crohn's Disease Treated?

There is no one cure for Crohn's disease. Treatment options are aimed to control the progression of the disease and the severity of the symptoms. If the disease goes into remission * , then such treatments help to minimize the chance that patients will relapse. When treatments are successful, most patients with Crohn's disease return to their normal daily lives.

Anti-inflammatory drugs are commonly the first step to treat Crohn's disease. Corticosteroids, mesalamine (Asacol, Rowasa), and sulfasalazine (Azulfidine) are among the anti-inflammatory drugs used.

Immune system suppressor drugs are used in some cases. Commonly used immune system suppressors are adalimumab (Humira), azathioprine (Imuran), infliximab (Remicade), and mercaptopurine (Purinetholand). Antibiotic drugs are used to control abscesses and fistulas and to reduce intestinal bacteria—both problems that cause more severe symptoms among patients with Crohn's disease. Two frequently used antibiotics are ciprofloxacin (Cipro) and metronidazole (Flagyl).

Other medicines used include antidiarrheals, laxatives, pain relievers, along with supplements, including calcium, iron, vitamin B12, and vitamin D. A special diet may be prescribed to reduce the severity of symptoms.

As a last resort to relieve symptoms, surgery may be performed to remove one or more inflamed or severely damaged sections of the digestive tract. Surgery may be recommended to eliminate fistulas or remove scar tissue. A surgical procedure is often used to widen a narrowed section of intestine. Many patients with Crohn's disease eventually have some type of surgery, and since the relief from surgery is temporary, many individuals have more than one surgery as their disease progresses.

The National Center for Complementary and Alternative Medicine (NCCAM) was established by the National Institutes of Health (NIH) to provide resources and information for the nontraditional treatment of diseases such as Crohn's disease. Medical studies have shown that one out of two persons with Crohn's disease tries complementary or alternative therapies and medicines. Medical science has not determined if these nontraditional treatments work. For the most part, the Food and Drug Administration does not regulate herbal and nutritional supplements used in such treatments. In addition, most Crohn's disease patients do not report nontraditional medicines to their family doctor, so their effectiveness has not been well documented. The website of NCCAM is .

Crohn's Disease—Points to Remember

Who Gets Crohn's Disease?

It has been estimated that about 201 per 100,000 adults and 43 per 100,000 children in the United States have Crohn's disease. Men and women are equally at risk for getting the symptoms associated with the disease. People of all ages can develop the condition. Teenagers and young adults in their 20s and 30s are most likely to get it, followed by people in their 50s to 70s.

Any ethnic group can develop Crohn's disease. Caucasians have the highest risk. People of Jewish and European descent are four to five times more likely to get the disease than any other ethnic group.

A person's immediate family is another important consideration when evaluating risk. If a person within an immediate family has Crohn's disease, then the other family members are at least 30 times more likely to get it than anybody else outside that family.

In addition, a person who uses tobacco is more likely to develop Crohn's disease than a nonsmoker. The use of tobacco products during treatment also makes the disease much more difficult to treat successfully.

The physical environment in which people live is thought to be a contributing factor for developing Crohn's disease. Studies have found that people living in industrialized countries, especially those inside heavily polluted cities, are at higher risk for the disease than people living in nonindustrialized countries and cities with clean air.

See also Inflammatory Bowel Syndrome


Books and Articles

Chastang, D. “Inflammatory Bowel Disease: Caring for a Patient with Crohn's Disease.” Medsurg Nursing 24, no. 4 (July-August 2015): 272–276.

Moghadamyeghaneh, Z., et al. “Outcomes of Bowel Resection in Patients with Crohn's Disease.” The American Surgeon 81 no. 10 (October, 2015): 1021–1027.

Nicholls, Kathleen. Go Your Crohn Way: A Gutsy Guide to Living with Crohn's Disease. Philadelphia: Singing Dragon, 2015.

Rajesh, Arumugam, ed. Crohn's Disease: Current Concepts. New York: Springer, 2015.

Rosen, M.J., A. Dhawan, and S.A. Saeed. “Inflammatory Bowel Disease in Children and Adolescents.” JAMA Pediatrics 169, no. 11 (November 2015): 1053–1060.


Mayo Clinic. “Crohn's Disease.” (accessed March 4, 2016).


Crohn's & Colitis Foundation of America. 733 Third Ave., Suite 510, New York, NY 10017. Toll-free: 800-932-2423. Website: (accessed March 4, 2016).

* ulcers are open sores on the skin or the lining of a hollow body organ, such as the stomach or intestine. They may or may not be painful.

* abscess (AB-ses) is a localized or walled-off accumulation of pus caused by infection that can occur anywhere in the body.

* bile duct is a passageway that carries bile, a substance that aids the digestion of fat, from the liver to the gallbladder (a small pouch-like organ where the bile is temporarily stored) and from the gallbladder to the small intestine.

* computed tomography (kom-PYOO-ter toe-MAH-gruhfee) or CT, also called computerized axial tomography (CAT), is a technique in which a machine takes many x-rays of the body to create a three-dimensional picture.

* autoimmune diseases (awtoh- ih-MYOON) are diseases in which the body's immune system attacks some of the body's own normal tissues and cells.

* immune system (im-YOON SIStem) is the system of the body composed of specialized cells and the substances they produce that help protect the body against disease-causing germs.

* remission is an easing of a disease or its symptoms for a prolonged period.

Disclaimer:   This information is not a tool for self-diagnosis or a substitute for professional care.

(MLA 8th Edition)