Ulcerative colitis: diagnosis and management

What is it, and who gets it?

Ulcerative colitis is a form of inflammatory bowel disease characterised by diffuse inflammation of the colonic mucosa. It affects the rectum and extends proximally along a variable length of the colon. The disease can be categorised as left sided colitis (inflammation up to the splenic flexure) or extensive colitis (inflammation beyond the splenic flexure). These categories are useful when formulating treatment options and planning the timing of surveillance colonoscopy, which is used to detect and prevent colorectal carcinoma. Colitis affects about one in 1000 people in the Western world.

What causes it?

The cause of inflammatory bowel disease is unclear, but it seems to occur in genetically susceptible people in response to environmental triggers. Ulcerative colitis is probably an autoimmune disease initiated by an inflammatory response to colonic bacteria.1 From 10% to 20% of patients with the disease have at least one family member with inflammatory bowel disease (ulcerative colitis or Crohn's disease).1

Non-steroidal anti-inflammatory drugs can cause a flare-up of disease in some patients with inflammatory bowel disease.2 Paracetamol is probably a safer option for analgesia, although mild non-steroidal anti-inflammatory drugs, such as ibuprofen, may be used occasionally if patients are told about the possibility of an increased risk of relapse. In contrast to Crohn's disease, smoking decreases the risk of ulcerative colitis.3 Up to 50% of relapses of colitis are associated with gastroenteritis due to recognised pathogens.4