Ulcerative colitis is an autoimmune condition that affects the gastrointestinal tract (gut).
It falls into a group of conditions called inflammatory bowel disease.
Ulcerative colitis predominantly affects the large bowel (colon). At times, ulcerative colitis may also affect other parts of the body, such as the skin, joints and eyes.
Ulcerative colitis is most commonly diagnosed in adolescents and young adults, however it can be diagnosed at any age.