Crohn's disease

Last reviewed: 7 Jun 2022
Last updated: 07 Dec 2021

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • abdominal pain
  • prolonged diarrhoea
  • perianal lesions
More key diagnostic factors

Other diagnostic factors

  • bowel obstruction
  • blood in stools
  • fever
  • fatigue
  • abdominal tenderness
  • weight loss
  • oral lesions
  • abdominal mass
  • extra-intestinal manifestations (e.g., erythema nodosum or pyoderma gangrenosum)
Other diagnostic factors

Risk factors

  • white ancestry
  • age 15-40 or 50-60 years
  • family history of CD
  • cigarette smoking
  • diet high in refined sugar
  • diet low in fibre
  • oral contraceptive pill
  • not breastfed
  • non-steroidal anti-inflammatory drugs (NSAIDs)
More risk factors

Diagnostic investigations

1st investigations to order

  • FBC
  • iron studies (serum iron, serum ferritin, total iron binding capacity [TIBC], transferrin saturation)
  • serum vitamin B12
  • serum folate
  • comprehensive metabolic panel (CMP)
  • C-reactive protein (CRP) and erythrocyte sedimentation rate (ESR)
  • stool testing
  • Yersinia enterocolitica serology
  • plain abdominal x-ray
  • MRI abdomen/pelvis
  • CT abdomen
More 1st investigations to order

Investigations to consider

  • abdominal and pelvic ultrasonography
  • ileocolonoscopy
  • tissue biopsy
  • oesophagogastroduodenoscopy
  • wireless capsule endoscopy
  • faecal calprotectin or faecal lactoferrin
More investigations to consider

Emerging tests

  • serological markers

Treatment algorithm

ACUTE

ileocaecal disease not fistulating with <100 cm of bowel affected: initial presentation or relapse

colonic disease not fistulating: initial presentation or relapse

extensive small bowel disease (>100 cm of bowel affected) not fistulating: initial presentation or relapse

upper GI disease (oesophageal and/or gastroduodenal disease) not fistulating: initial presentation or relapse

perianal or fistulating disease: initial presentation or relapse

ONGOING

in remission

Contributors

Authors

George Reese, MBBS, FRCS

Consultant Colorectal Surgeon

Imperial College Healthcare NHS Trust

London

UK

Disclosures

GR is an author of a number of references cited in this topic.

Georgia Woodfield, MD

SpR in Gastroenterology and General Medicine

Imperial College Healthcare NHS Trust

Research Fellow

Imperial College London

London

UK

Disclosures

GW declares that she has no competing interests.

Pranav H. Patel, MD

SpR in General Surgery

Imperial College Healthcare

Research Fellow

Imperial College London

London

UK

Disclosures

PHP declares that he has no competing interests.

Acknowledgements

Mr George Reese, Dr Georgia Woodfield, and Dr Pranav H. Patel would like to gratefully acknowledge Dr Philip J. Smith, Dr Charlotte Ford, Dr Wissam Bleibel, Dr Bishal Mainali, Dr Chandrashekhar Thukral, and Dr Mark A. Peppercorn, the previous contributors to this topic.

Disclosures

PJS, CF, WB, BM, CT, and MAP declare that they have no competing interests.

Peer reviewers

Kiron M. Das, MD, PhD, FACP, FRCP

Chief of Gastroenterology & Hepatology

Professor of Medicine

Director of Crohn's & Colitis Center of New Jersey

New Brunswick

NJ

Disclosures

KMD declares that he has no competing interests.

John Mansfield, MA, MD, FRCP

Consultant Gastroenterologist and Senior Lecturer

Royal Victoria Infirmary

Newcastle upon Tyne Hospitals NHS Foundation Trust and Newcastle University

Newcastle upon Tyne

UK

Disclosures

JM declares that he has no competing interests.

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