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Ulcerative colitis

Last reviewed: 4 Sep 2023
Last updated: 01 Jun 2023



History and exam

Key diagnostic factors

  • rectal bleeding
  • diarrhea
  • blood in stool
More key diagnostic factors

Other diagnostic factors

  • abdominal pain
  • arthritis and spondylitis
  • malnutrition
  • abdominal tenderness
  • fever
  • weight loss
  • constipation
  • skin rash
  • uveitis and episcleritis
  • pallor
Other diagnostic factors

Risk factors

  • family history of inflammatory bowel disease
  • human leukocyte antigen-B27
  • infection
  • nonsteroidal anti-inflammatory drugs (NSAIDs)
  • not smoking or former smoker
More risk factors

Diagnostic investigations

1st investigations to order

  • stool studies for infective pathogens
  • fecal calprotectin
  • CBC
  • comprehensive metabolic panel (including LFTs)
  • erythrocyte sedimentation rate (ESR)
  • CRP
  • plain abdominal radiograph
  • flexible sigmoidoscopy
  • colonoscopy
  • biopsies
More 1st investigations to order

Investigations to consider

  • CT scan
More investigations to consider

Treatment algorithm


acute severe ulcerative colitis

moderate-to-severe disease

mild disease


disease in remission



Andrew Poullis, BSc, MBBS, MD, FRCP

Consultant Gastroenterologist

Department of Gastroenterology

St George’s Hospital




AP is an author of a reference cited in this topic.

Aaron Bhakta, BMedSci (Hons), BMBS, MSc, MRCP

Clinical Fellow in Gastroenterology

Department of Gastroenterology

St George’s Hospital




AB declares that he has no competing interests.


Dr Hesam A. Nooredinvand, and Dr Andrew Poullis would like to gratefully acknowledge Dr Ben Shandro, Dr Anet Soubieres, Dr Rhys Hewett, Dr Willem J.S. de Villiers, and Dr Houssam Mardini, previous contributors to this topic.


BS, AS, RH, WJSD, and HM declare that they have no competing interests.

Peer reviewers

Trevor Winter, MD, PhD

Associate Professor of Medicine

Division of Digestive Diseases and Nutrition

University of Kentucky




TW declares that he has no competing interests.

Sharon Stein, MD

Assistant Professor of Surgery

Division of Colon and Rectal Surgery

University Hospital Case Medical Center




SS received a fee for educational courses on laparoscopic surgery, paid for in part by Covidien, Olympus, and Applied Medical.

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