What is Crohn's disease?

Crohn’s disease is a lifelong form of inflammatory bowel disease (IBD). The condition inflames and irritates the digestive tract (specifically the small and large intestines). It causes diarrhea and stomach cramps. It’s common to have periodic disease flare-ups.

Crohn’s disease gets its name from American gastroenterologist Dr. Burrill Crohn (1884-1983), one of the first physicians to describe the illness in 1932. Ulcerative colitis is another commonly diagnosed IBD.

How common is Crohn’s disease?

An estimated half a million Americans have Crohn’s disease.

Who might get Crohn’s disease?

Crohn’s disease typically appears when people are in their 20s, but it can occur at any age. Cigarette smokers are more likely than non-smokers to develop Crohn’s disease.

What are the types of Crohn’s disease?

Crohn’s disease can affect different sections of the digestive tract. Types of Crohn’s disease include:

  • Ileocolitis: Inflammation occurs in the small intestine and part of the large intestine, or colon. Ileocolitis is the most common type of Crohn’s disease.
  • Ileitis: Swelling and inflammation develop in the small intestine (ileum).
  • Gastroduodenal: Inflammation and irritation affect the stomach and the top of the small intestine (the duodenum).
  • Jejunoileitis: Patchy areas of inflammation develop in the upper half of the small intestine (called the jejunum).

What causes Crohn's disease?

Crohn’s disease has no known cause. Certain factors may increase your risk of developing the condition, such as:

  • Autoimmune disease: Bacteria in the digestive tract may cause the body’s immune system to attack healthy cells.
  • Genes: IBD often runs in families. Having a parent or sibling with Crohn’s diseases increases your risk. There are several specific mutations that can predispose patients to developing Crohn’s disease.
  • Smoking: Cigarette smoking may as much as double Crohn’s disease risk.

What are the symptoms of Crohn’s disease?

People with Crohn’s disease experience periods of severe symptoms (flare-ups) followed by periods of no or very mild symptoms (remission). Remission can last weeks or even years. There’s no way to predict when flare-ups will occur. People with Crohn’s disease may experience:

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