Definition & Facts for Crohn’s Disease
In this section:
- What is Crohn’s disease?
- How common is Crohn’s disease?
- Who is more likely to develop Crohn’s disease?
- What are the complications of Crohn’s disease?
- What other health problems do people with Crohn’s disease have?
What is Crohn’s disease?
Crohn’s disease is a chronic disease that causes inflammation and irritation in your digestive tract. Most commonly, Crohn’s affects your small intestine and the beginning of your large intestine. However, the disease can affect any part of your digestive tract, from your mouth to your anus. Learn more about your digestive system and how it works.
Crohn’s disease is an inflammatory bowel disease (IBD). Ulcerative colitis and microscopic colitis are other common types of IBD.
Crohn’s disease most often begins gradually and can become worse over time. You may have periods of remission that can last for weeks or years.
How common is Crohn’s disease?
Researchers estimate that more than half a million people in the United States have Crohn’s disease.1 Studies show that, over time, Crohn’s disease has become more common in the United States and other parts of the world.1,2 Experts do not know the reason for this increase.
Who is more likely to develop Crohn’s disease?
Crohn’s disease can develop in people of any age and is more likely to develop in people
- between the ages of 20 and 292
- who have a family member, most often a sibling or parent, with IBD
- who smoke cigarettes
What are the complications of Crohn’s disease?
Complications of Crohn’s disease can include the following:
- Intestinal obstruction. Crohn’s disease can thicken the wall of your intestines. Over time, the thickened areas of your intestines can narrow, which can block your intestines. A partial or complete intestinal obstruction, also called a bowel blockage, can block the movement of food or stool through your intestines.
- Fistulas. In Crohn’s disease, inflammation can go through the wall of your intestines and create tunnels, or fistulas. Fistulas are abnormal passages between two organs, or between an organ and the outside of your body. Fistulas may become infected.
- Abscesses. Inflammation that goes through the wall of your intestines can also lead to abscesses. Abscesses are painful, swollen, pus-filled pockets of infection.
- Anal fissures. Anal fissures are small tears in your anus that may cause itching, pain, or bleeding.
- Ulcers. Inflammation anywhere along your digestive tract can lead to ulcers or open sores in your mouth, intestines, anus, or perineum.
- Malnutrition. Malnutrition develops when your body does not get the right amount of vitamins, minerals, and nutrients it needs to maintain healthy tissues and organ function.
- Inflammation in other areas of your body. You may have inflammation in your joints, eyes, and skin.
What other health problems do people with Crohn’s disease have?
If you have Crohn’s disease in your large intestine, you may be more likely to develop colon cancer. If you receive ongoing treatment for Crohn’s disease and stay in remission, you may reduce your chances of developing colon cancer.3
Talk with your doctor about how often you should get screened for colon cancer. Screening is testing for diseases when you have no symptoms. Screening for colon cancer can include colonoscopy with biopsies. Although screening does not reduce your chances of developing colon cancer, it may help to find cancer at an early stage and improve the chance of curing the cancer.
This content is provided as a service of the National Institute of Diabetes and Digestive and Kidney Diseases
(NIDDK), part of the National Institutes of Health. The NIDDK translates and disseminates research findings to increase knowledge and understanding about health and disease among patients, health professionals, and the public. Content produced by the NIDDK is carefully reviewed by NIDDK scientists and other experts.