Inflammation of the colon, especially of its mucous membranes. The inflamed membranes develop patches of tiny ulcers, and the diarrhea contains blood and mucus. It often becomes chronic, with sustained fever and weight loss; complications and death may result. Specific causes, such as amoebic or bacillary dysentery, are rarer than unknown or multiple causes. If treatment with sulfasalazine, corticosteroids, immunosuppressive drugs, or antibiotics does not control it, part or all of the colon may have to be removed.

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