HEALTH TOPICS 
Crohn's Disease
What Is It?
Crohn's disease is an inflammatory bowel disease in which inflammation injures the intestines. It is a long-term (chronic) condition. Crohn's disease typically begins between ages 15 and 40.
No one knows for sure what triggers the initial intestinal inflammation at the start of Crohn's disease. A viral or bacterial infection may start the process by activating the immune system in the intestine. However, the immune system attack is not turned off: it stays active and creates inflammation even after the infection goes away.
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