Crohn’s disease and ulcerative colitis are collectively known as inflammatory bowel disease (IBD). Both conditions affect the bowel, but in slightly different ways. Crohn’s disease causes inflammation of the full thickness of the bowel wall, in any part of the digestive tract from the mouth to the anus. Ulcerative colitis is inflammation of the inner lining of the large bowel (colon and rectum).
In Crohn’s patients, their immune system attacks healthy body cells due to abnormal regulation of the white blood cells in their body. The term weakened immune system or immune suppression often describes the lack of an appropriate response by the body to fight harmful germs.
Ulcerative colitis is an autoimmune condition in which the immune system attacks healthy tissue in the gut. This causes inflammation of the large intestine, which causes the symptoms of UC. Without proper treatment, UC could lower the immune system.