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Learning About Crohn's Disease

What is Crohn's disease?

Crohn's disease, an idiopathic (of unknown cause), chronic inflammatory disorder of the bowel, involves any region of the gastrointestinal tract from the mouth to the anus. The swelling and inflammation can go deeply into the lining of the bowel. This can be very painful and can cause diarrhea, abdominal pain, nausea and decreased appetite. The inflammatory process tends to be eccentric and segmental, often with skip areas (normal regions of bowel between inflamed areas).

Complications of Crohn's disease include: blockage of the intestine; sores and ulcers in the affected area or surrounding tissues such as the bladder; tunnels around the anus and rectum called fistulas; nutritional deficiencies; anemia; arthritis; skin problems; kidney stones, gallstones or other diseases of the liver and biliary system.

Both men and women can have Crohn's disease. It can also run in families. About 20 percent (1 in 5) of people who have Crohn's disease have a blood relative with some form of inflammatory bowel disease, usually a brother or a sister, and sometimes a parent and child.

Crohn's disease is usually diagnosed in people between the ages of 20 - 30. About 25 percent of new Crohn's disease diagnoses are made in persons who are younger than 20 years of age.

When given proper medical care, most people who have Crohn's disease are able to lead long and productive lives. New medications and research into the causes of Crohn's disease are helping to increase the quality of life for people who have Crohn's disease.

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What are the symptoms of Crohn's disease?

The symptoms of Crohn's disease include:
  • Abdominal pain, often in the lower right area.
  • Diarrhea
  • Rectal bleeding
  • Weight loss
  • Arthritis
  • Skin problems
  • Fever

Rectal bleeding may be serious and continuous enough to cause anemia (low red blood count).

Children who have Crohn's disease may have delayed development and stunted growth.

The range and severity of the symptoms of Crohn's disease varies among individuals.

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How is Crohn's disease diagnosed?

Crohn's disease is diagnosed by a thorough physical exam and a series of tests.

Blood tests may be done to:
  • Check for anemia.
  • Check for a high white blood cell count and sedimentation rate which are signs of swelling (inflammation) in the body.
Other tests that may be done include:
  • A stool sample to check to see if there is any bleeding or infection in the intestines.
  • An X-ray called an upper GI series with small bowel follow-through to look at the small intestine.
  • A visual exam of the colon using sigmoidoscopy or colonoscopy that allows the doctor to see any inflammation or bleeding in the colon.

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What is the treatment for Crohn's disease?

There is currently no cure for Crohn's disease. The treatment for Crohn's disease usually involves medical care over a long period of time, with regular visits to the doctor to monitor the condition.

Treatment includes: drugs, nutrition supplements and surgery, or a combination of these treatments. The goal of treatment is to control the swelling (inflammation), correct any nutritional deficiencies, and relieve symptoms such as abdominal pain, diarrhea and rectal bleeding.

Drug therapy for Crohn's disease includes:
  • Anti-inflammation drugs such as sulfasalazine.
  • Cortisone or steroids (corticosteroids) such as prednisone.
  • Immune system suprressors, such as 6-mercaptopurine or a related drug, azothioprine.
  • Infliximab (Remicade), a drug that is the first of a group of medications that blocks the body's inflammation process.
  • Antibiotics to treat bacterial overgrowth in the intestine or before surgery.
  • Anti-diarrhea medications and fluid replacements.

Nutrition supplements may be recommended especially for children whose growth has been slowed. For some patients, this nutrition is given intravenously through a small tube in the arm.

While a patient may require colectomy for uncontrolled bleeding, this is increasingly rare in Crohn's, especially with new immune therapies.

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Is Crohn's disease inherited?

There appears to be a risk for inheriting Crohn's disease, especially in families of Jewish ancestry.

Children who have one parent with Crohn's disease have a 7 to 9 percent lifetime risk of developing the condition. They also have a 10 percent chance to develop some form of inflammatory bowel disease. When both parents have inflammatory bowel disease, the risk for their children to develop Crohn's disease is 35 percent.

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NHGRI Clinical Research on Crohn's Disease

Currently, NHGRI is not conducting clinical research on Crohn's disease.

However, there are studies listed on being conducted at other institutes at the National Institutes of Health:

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Additional Resources for Crohn's Disease

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Last Updated: September 27, 2011

See Also:

Talking Glossary
of Genetic Terms

Definitions for genetic terms used on this page.