Summary
Definition
History and exam
Key diagnostic factors
- history of inflammatory bowel disease
- history of exposure to infectious agents
- history of recent antibiotic use
- history of HIV/AIDS/immunosuppressed state
- fevers/chills
- tachycardia
- mental status changes
- hypotension
- abdominal distention
Other diagnostic factors
- diarrhea
- abdominal pain
- abdominal tenderness
Risk factors
- ulcerative colitis (UC)
- Crohn colitis
- pseudomembranous colitis
- infectious colitis
- HIV/AIDS/immunosuppression
- discontinuation of drug treatments for inflammatory bowel disease
- use of antimotility drugs
- use of chemotherapy or immunosuppressants
- electrolyte abnormalities
Diagnostic tests
1st tests to order
- CBC
- serum urea and electrolytes
- serum albumin levels
- serum lactate
- stool studies
- CT abdomen/pelvis
- abdominal x-ray
- chest x-ray
Tests to consider
- CRP
- erythrocyte sedimentation rate (ESR)
- blood cultures
- arterial blood gas
- flexible sigmoidoscopy
- rectal biopsy
- surgical specimen
Treatment algorithm
all patients
Contributors
Authors
Jan Rakinic, MD
Chief
Colorectal Surgery
Department of Surgery
Southern Illinois University School of Medicine
Springfield, IL
Disclosures
JR declares that she has no competing interests.
V. Prasad Poola, MBBS, FACS, FASCRS
Associate Professor of Surgery
Department of Surgery
Southern Illinois University School of Medicine
Springfield, IL
Disclosures
VPP declares that he has no competing interests.
Acknowledgements
Dr Jan Rakinic and Dr V. Prasad Poola would like to gratefully acknowledge Dr Scott A. Strong, Dr Mukta V. Krane, and Dr Alessandro Fichera, previous contributors to this topic.
Disclosures
SAS, MVK, and AF declare that they have no competing interests.
Peer reviewers
Marianne V. Cusick, MD, MSPH
Divisional Director
Colon & Rectal Surgery
UTHealth Houston
Houston, TX
Disclosures
MVC declares that she has no competing interests.
Sharon Stein, MD
Assistant Professor of Surgery
Division of Colon and Rectal Surgery
University Hospital Case Medical Center
Cleveland, OH
Disclosures
SS received a fee for educational courses on laparoscopic surgery, paid for in part by Covidien, Olympus, and Applied Medical.
David J. Hackam, MD, PhD
Associate Professor of Pediatric Surgery
University of Pittsburgh School of Medicine
Pittsburgh, PA
Disclosures
DJH declares that he has no competing interests.
James Wheeler, MB, BCh, MD, FRCS
Consultant
Colorectal Surgeon
Addenbrookes Hospital
Cambridge
UK
Disclosures
JW declares that he has no competing interests.
Peer reviewer acknowledgements
BMJ Best Practice topics are updated on a rolling basis in line with developments in evidence and guidance. The peer reviewers listed here have reviewed the content at least once during the history of the topic.
Disclosures
Peer reviewer affiliations and disclosures pertain to the time of the review.
References
Key articles
Rubin DT, Ananthakrishnan AN, Siegel CA, et al. ACG clinical guideline update: ulcerative colitis in adults. Am J Gastroenterol. 2025 Jun 3;120(6):1187-224.Full text Abstract
Poylin V, Hawkins AT, Bhama AR, et al. The American Society of Colon and Rectal Surgeons clinical practice guidelines for the management of Clostridioides difficile infection. Dis Colon Rectum. 2021 Jun 1;64(6):650-68.Full text
Kelly CR, Fischer M, Allegretti JR, et al. ACG clinical guidelines: prevention, diagnosis, and treatment of Clostridioides difficile infections. Am J Gastroenterol. 2021 Jun 1;116(6):1124-47.Full text Abstract
McDonald LC, Gerding DN, Johnson S, et al. Clinical practice guidelines for Clostridium difficile infection in adults and children: 2017 update by the Infectious Diseases Society of America (IDSA) and Society for Healthcare Epidemiology of America (SHEA). Clin Infect Dis. 2018 Mar 19;66(7):987-94.Full text Abstract
Holubar SD, Lightner AL, Poylin V, et al. The American Society of Colon and Rectal Surgeons clinical practice guidelines for the surgical management of ulcerative colitis. Dis Colon Rectum. 2021 Jul 1;64(7):783-804.Full text
Reference articles
A full list of sources referenced in this topic is available to users with access to all of BMJ Best Practice.

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