 [ Symptoms ] what is the difference between ulcerative colitis crohn is disease and irritable bowel syndrome [ Disease ] ulcerative colitis is an inflammatory bowel disease of the colon also called the large intestine and rectum that causes inflammation and ulcers of the intestinal wall diarrhea and abdominal pain crohn is disease is also an inflammatory bowel disease with similar symptoms but it can affect any part of the digestive tract irritable bowel syndrome is not an inflammatory bowel disease it is a milder disorder without damage or inflammation of the intestinal lining