Colitis is swelling (inflammation) of the large intestine (colon).
Causes of colitis include:
- Infections, including those caused by a virus, parasite, and food poisoning due to bacteria
- Ulcerative colitis and Crohn disease
- Lack of blood flow (ischemic colitis)
- Past radiation to the large bowel
- Necrotizing enterocolitis in newborns
- Pseudomembranous colitis
Symptoms can include:
- Abdominal pain and bloating that may be constant, or come and go
- Bloody stools
- Constant urge to have a bowel movement
Exams and Tests
The health care provider will perform a physical exam. You will also be asked questions about your symptoms such as:
- How long have you had the symptoms?
- How severe is your pain?
- How often do you have pain and how long does it last?
- How often do you have diarrhea?
- Have you been traveling?
The provider can diagnose colitis by inserting a flexible tube into the rectum (flexible sigmoidoscopy or colonoscopy) and looking at certain areas of the colon. You may have biopsies taken during this exam. Biopsies may show changes related to inflammation. This can help determine the cause of colitis.
Other studies that can identify colitis include:
Your treatment will depend on the cause of the disease.
The outlook will vary, depending on the cause of the problem.
Complications may include:
- Hole in the colon
- Toxic megacolon
- Sore (ulceration)
When to Contact a Medical Professional
Call your provider if you have symptoms such as:
- Abdominal pain that does not get better
- Blood in the stool or stools that look black
- Diarrhea or vomiting that does not go away
- Swollen abdomen
Horn AE, Ufbert JW. Appendicitis, diverticulitis, and colitis. Emerg Med Clin N Am. 2011;29:347-368. PMID: 21515183 www.ncbi.nlm.nih.gov/pubmed/21515183.
Osterman MT, Lichtenstein GR. Ulcerative colitis. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran’s Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 116.
Wald A. Other diseases of the colon and rectum. In: Feldman M, Friedman LS, Brandt LJ, eds. Sleisenger & Fordtran’s Gastrointestinal and Liver Disease. 10th ed. Philadelphia, PA: Elsevier Saunders; 2016:chap 128.
Ulcerative colitis - illustration
Large intestine - illustration
Large intestine (colon) - illustration
Large intestine (colon)
Crohn disease, X-ray - illustration
Crohn disease, X-ray
Review Date: 8/14/2015
Reviewed By: Subodh K. Lal, MD, gastroenterologist with Gastrointestinal Specialists of Georgia, Austell, GA. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.