People with IBS can get mucus too and there is no inflammation with IBS...
However, the large bowel mucus layer effectively prevents contact between the highly concentrated luminal bacteria and the epithelial cells in all parts of the normal colon. Colonic inflammation is always accompanied by breaks in the mucus barrier. Although the inflammatory response gradually reduces the number of bacteria in mucus and faeces, the inflammation itself is not capable of preventing bacterial migration, adherence to and invasion of the mucosa.
In UC, the mucus membrane of the intestine becomes inflamed and develops ulcers. These ulcers bleed and produce pus and mucus, which may be visible as they are passed in the stool. In IBS, there may be increased mucus production by the lining of the intestine, which is then passed. Mucus is more often associated with diarrhea-predominant IBS. Mucus is less frequent with CD, but may be associated with the development of an anal fissure.
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