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Last reviewed: 16 Mar 2025
Last updated: 06 Feb 2025

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors
  • diarrhoea
  • abdominal pain

Other diagnostic factors

  • fever
  • abdominal tenderness
  • nausea and vomiting
  • abdominal distension
  • symptoms of shock

Risk factors

  • antibiotic exposure
  • advanced age
  • hospitalisation or residence in a nursing home
  • exposure to infected family member
  • history of Clostridioides difficile-associated disease
  • use of acid-suppressing drugs
  • inflammatory bowel disease
  • solid organ transplant recipients
  • haematopoietic stem cell transplant recipients
  • chronic kidney disease
  • HIV infection
  • immunosuppressive agents or chemotherapy
  • gastrointestinal surgery
  • vitamin D deficiency
  • consumption of C difficile contaminated food

Diagnostic investigations

1st investigations to order

  • FBC
  • stool guaiac (faecal occult blood test)
  • stool polymerase chain reaction (PCR)
  • stool immunoassay for glutamate dehydrogenase
  • stool immunoassay for toxins A and B
  • abdominal x-ray

Investigations to consider

  • cell culture cytotoxicity neutralisation assay
  • CT abdomen
  • sigmoidoscopy or colonoscopy

Emerging tests

  • stool lactoferrin or calprotectin

Treatment algorithm

Contributors

Authors

Ali Hassoun, MD, FACP, FIDSA, AAHIVS

Clinical Associate Professor of Medicine

Alabama Infectious Diseases Center

Huntsville

AL

Disclosures

AH declares that he has no competing interests.

Peer reviewers

Gregory R. Madden, MD, MSDS

Assistant Professor

Division of Infectious Diseases and International Health

University of Virginia School of Medicine

Charlottesville

VA

Disclosures

GRM declares that he has no competing interests.

Satish Keshav, MBBCh, DPhil, FRCP

Consultant Gastroenterologist

Department of Gastroenterology

John Radcliffe Hospital

Oxford

UK

Disclosures

SK declares that he has no competing interests.

Ian Beales, MD, FRCP

Clinical Reader and Consultant Gastroenterologist

Norfolk and Norwich University Hospital

Norwich

UK

Disclosures

IB declares that he has no competing interests.

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