Colitis is swelling (inflammation) of the colon. The colon makes up most of the large intestine. It can be caused by different things, such as an infection or loss of blood flow in the intestine. Other causes are problems like Crohn’s disease or ulcerative colitis.
Symptoms may include fever, diarrhea that may be bloody, or belly pain. You may also have an urgent need to move your bowels or pain when you move your bowels. You may have bleeding from the rectum or weight loss.
Your symptoms may depend on the type of colitis you have. For example, microscopic colitis may cause watery diarrhea.
Sometimes symptoms go away on their own. If they don't go away, or if you have bleeding or severe pain, call your doctor right away.
You may need blood tests or a stool test. You also may need imaging tests like a CT scan. You may have a colonoscopy so that a doctor can look inside your colon. In some cases, the doctor may want to test a sample of tissue from the intestine. This test is called a biopsy.