Definition and diagnosis of ulcerative colitis in adults

Ulcerative colitis is a chronic, relapsing, immune-mediated inflammatory disease of the colon, which can be associated with a range of extra-intestinal manifestations (eg arthropathy, skin manifestations [eg pyoderma gangrenosum, erythema nodosum], ocular manifestations [eg uveitis, scleritis, episcleritis], and hepatobiliary disease)Lichtenstein, 2018. Both genetic and environmental factors are important in its aetiology.

Intestinal inflammation in ulcerative colitis is generally limited to the mucosal layer of the colon and is continuous, extending from the rectum for a variable distance towards the caecum. Typical symptoms include diarrhoea, urgency or tenesmus (due to rectal inflammation) and blood in the stools.

Diagnosis of ulcerative colitis is made if typical features are seen on endoscopic and histological investigations and infectious causes have been excluded.

Faecal calprotectin testing can be very useful to rule out ulcerative colitis; it has a negative predictive value approaching 100% using a cut-off of 50 micrograms/g of stoolAn, 2019. Faecal calprotectin testing is less sensitive for detecting proximal small bowel inflammation.

For information about inflammatory bowel disease in children, see Inflammatory bowel disease in children.