Topic Overview

What is Crohn's disease?

Crohn's disease is a lifelong inflammatory bowel disease (IBD). Parts of the digestive system get swollen and have deep sores called ulcers. Crohn’s disease usually is found in the last part of the small intestine and the first part of the large intestine. But it can develop anywhere in the digestive tract, from the mouth to the anus.

What causes Crohn's disease?

Doctors don't know what causes Crohn’s disease. You may get it when the body’s immune system has an abnormal response to normal bacteria in your intestine. Other kinds of bacteria and viruses may also play a role in causing the disease.

Crohn’s disease can run in families. Your chances of getting it are higher if a close family member has it. People of Eastern European (Ashkenazi) Jewish family background may have a higher chance of getting Crohn’s disease. Smoking also puts you at a higher risk for the disease.

What are the symptoms?

The main symptoms of Crohn’s disease are belly pain and diarrhea (sometimes with blood). Some people may have diarrhea 10 to 20 times a day. Losing weight without trying is another common sign. Less common symptoms include mouth sores, bowel blockages, anal tears (fissures), and openings (fistulas) between organs.

Infections, hormonal changes, and smoking can cause your symptoms to flare up. You may have only mild symptoms or go for long periods of time without any symptoms. A few people have ongoing, severe symptoms.

It’s important to be aware of signs that Crohn’s disease may be getting worse. Call your doctor right away if you have any of these signs:

• You feel faint or have a fast and weak pulse.
• You have severe belly pain.
• You have a fever or shaking chills.
• You are vomiting again and again.

How is Crohn's disease diagnosed?

Your doctor will ask you about your symptoms and do a physical exam. You may also have X-rays and lab tests to find out if you have Crohn’s.

Tests that may be done to diagnose Crohn's disease include:

• Barium X-rays of the small intestine or colon.
• Colonoscopy or flexible sigmoidoscopy. In these tests, the doctor uses a thin, lighted tube to look inside the colon.
• Biopsy. The doctor takes a sample of tissue and tests it to find out if you have Crohn’s or another disease, such as cancer.
• Stool analysis. This is a test to look for blood and signs of infection in a sample of your stool.