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Ulcerative colitis (UC) is a type of inflammatory bowel disease (IBD) that affects the mucosal and the submucosal layers of the colon and rectum, and sometimes a short segment of terminal ileum. Severe UC is characterized by fever, abnormal levels of C-reactive protein and haemoglobin, as well as other signs of bowel inflammation. Estimates of the prevalence of UC range from 7 to 246 per 100,000 individuals. Complications of UC may be local, including haemorrhoids, perirectal abscesses or anal fissures. However, extraintestinal manifestations may also occur.