Ulcerative colitis (UC) is a chronic inflammatory condition that only affects the rectum and large bowel. The cause is unknown. It can occur at any age but most commonly in ages 20s to 40s. It can also occur in the elderly.


Inflammation always begins in the rectum and extends a variable distance towards the start of the large bowel. It is always continuous with no skip lesions (which is a feature of Crohn’s disease). Usual symptoms includes diarrhoea, passage of blood and mucus, urge to defaecate and abdominal pain. It may result in weight loss, anaemia, malnutrition and electrolyte imbalance. Severe complications such as toxic megacolon and perforation are uncommon but can be life threatening. UC increase the risk of bowel cancer and the risk increases with the duration of disease.

Diagnosis is made on symptoms, colonoscopy finding and biopsy results.


Most patients with UC are treated medically and best achieved by combined efforts between a gastroenterologist and a surgeon. Most medical treatments are based on anti-inflammatory medication or immunosuppresants. Some patients will require surgery and this will usually involve removing the entire large bowel with or without removal of the rectum as well. Indications of surgery include failure of medical treatment, complication of UC (such as toxic megacolon, perforation or acute haemorrhage) and development of malignancy in the large bowel.