Crohn Disease
Condition
(CD; Crohn's disease, Regional Enteritis)
Definition
Crohn disease is long-term inflammation and irritation in the digestive tract. It is a type of inflammatory bowel disease. Crohn disease can affect any part of the digestive tract from the mouth to the anus. It is more common in the end of the small intestine or the start of the large intestine.
When a person has symptoms of Crohn disease it is known as a flare up. When a person with Crohn disease has times where there are no symptoms, this is called remission.
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Causes
It is not clear what causes Crohn disease. Genes, the environment, and problems with the immune system may all play a role.
Risk Factors
The risk of Crohn disease is higher in those with:
- Family members who have Crohn disease
- Tobacco use disorder
- Low activity levels
- Disorders related to stress
- Regularly take medicines such as antibiotics and nonsteroidal anti-inflammatory drugs
- Digestive system infections such as salmonella or campylobacter gastroenteritis
Symptoms
During a Crohn disease flare up a person may have:
- Loose stools (poop)
- Belly cramps and pain
- Rectal bleeding
- Weight loss
- Weakness and lack of energy
- Nausea
- Fever
- Mouth sores
- Sores in the anal area
Diagnosis
The doctor will ask about symptoms and past health. A physical exam will be done. Blood and stool tests will be done to look for problems and rule out other issues. Scopes can be done to look for areas of inflammation. This can be done with:
- Upper endoscopy
- Colonoscopy
A small sample of intestine may be removed with a scope for biopsy. The sample will be sent to a lab for testing.
Other image tests may be used such as:
- Wireless capsule endoscopy—a tiny capsule is swallowed and then takes pictures of the digestive tract
- MRE, an MRI scan of the small intestines
Treatment
There is no cure. The goal of treatment during a flare up treatment is manage symptoms and try to prevent other problems. Treatment may also be used during remission to prevent flare ups. The treatment plan can vary. Some steps may include:
- Medicines to help:
- Reduce inflammation—Medicines may be taken for a short time to help with flare ups.
- Lower immune system response—Medicines may be taken for a long time to help prevent flare ups.
- Manage pain, diarrhea, or nausea.
- Bowel rest for severe inflammation—a person does not eat food and only drinks nutritious drinks until they are better.
- Nutrition support—vitamins or supplements are taken to help with nutrition during a flare up.
- Surgery to:
- Removed damaged parts of the intestine
- Help with very bad symptoms
- Treat problems cause by Crohn disease
Other treatment may be needed to treat other problems caused by Crohn disease.
Prevention
There are no known methods to prevent Crohn disease.
Crohn's & Colitis Foundation
National Institute of Diabetes and Digestive and Kidney Diseases
CANADIAN RESOURCES:
Crohn's and Colitis Canada
Health Canada
Crohn's & Colitis Foundation
National Institute of Diabetes and Digestive and Kidney Diseases
CANADIAN RESOURCES:
Crohn's and Colitis Canada
Health Canada
References
- Crohn disease. Merck Manual Professional Version website. Available at: http://www.merckmanuals.com/professional/gastrointestinal-disorders/inflammatory-bowel-disease-ibd/crohn-disease.
- Crohn disease in adults. EBSCO DynaMed website. Available at: https://www.dynamed.com/condition/crohn-disease-in-adults.
- Crohn's disease. National Institute of Diabetes and Digestive and Kidney Diseases website. Available at: https://www.niddk.nih.gov/health-information/digestive-diseases/crohns-disease.
- Lichtenstein, G.R., Loftus, E.V., et al. ACG Clinical Guideline: Management of Crohn's Disease in Adults. The American Journal of Gastroenterology, 2018; 113 (4): 481-517.
- What is Crohn's disease? Crohn's & Colitis Foundation website. Available at: http://www.crohnscolitisfoundation.org/what-are-crohns-and-colitis/what-is-crohns-disease.
Contributors
- James P. Cornell, MD
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