Irritable bowel syndrome
Summary
Definition
History and exam
Key diagnostic factors
- presence of risk factors
- abdominal pain
- alteration of bowel habits associated with pain
- abdominal bloating or distension
- normal examination of abdomen
Other diagnostic factors
- passage of mucus with stool
- urgency of defecation
Risk factors
- physical and sexual abuse
- post-traumatic stress disorder (PTSD)
- age <50 years
- female sex
- previous enteric infection
- family history
- family and job stress
Diagnostic investigations
1st investigations to order
- FBC
Investigations to consider
- faecal occult blood test
- quantitative faecal immunochemical test (FIT)
- serologic tests for coeliac disease
- faecal calprotectin
- faecal lactoferrin
- serum C-reactive protein (CRP)
- erythrocyte sedimentation rate (ESR)
- serum fibroblast growth factor 19
- 23‐seleno‐25‐homotaurocholic acid (SeHCAT) test
- 48-hour stool collection for total bile acids
- empiric trial of bile acid binder
- hydrogen/methane breath test
- stool tests for Giardia lamblia
- plain abdominal x-ray
- colonoscopy
- flexible sigmoidoscopy
Treatment algorithm
constipation-predominant
diarrhoea-predominant
alternating constipation and diarrhoea
Contributors
Authors
Ned Snyder, MD, MACP, AGAF
Professor of Medicine
Baylor College of Medicine and Marion DeBakey VA Hospital
Houston
TX
Adjunct Professor of Medicine
University of Texas Medical Branch
Galveston
TX
Disclosures
NS declares that he is a member on the board of the Kelsey Research Foundation, a non-profit organization. Kelsey Research Foundation has received and awarded private grants for the study of the microbiome in several diseases, including irritable bowel syndrome.
Peer reviewers
Douglas Drossman, MD
Professor of Medicine and Psychiatry
School of Medicine
Co-Director
UNC Center for Functional GI and Motility Disorders
Chapel Hill
NC
Disclosures
DD declares that he has no competing interests.
Simon McLaughlin, MBBS
Research Fellow
Department of Gastroenterology
St Mark's Hospital
Northwick Park
Harrow
UK
Disclosures
SM declares that he has no competing interests.
Horace Williams, MBBS
Clinical Research Fellow
Division of Medicine
Imperial College
London
UK
Disclosures
HW declares that he has no competing interests.
References
Key articles
Longstreth GF, Thompson WG, Chey WD, et al. Functional bowel disorders. Gastroenterology. 2006 Apr;130(5):1480-91.Full text Abstract
Lacy BE, Mearin F, Chang L, et al. Bowel disorders. Gastroenterology. 2016 May;150(6):1393-407. Abstract
Lacy BE, Pimentel M, Brenner DM, et al. ACG clinical guideline: management of irritable bowel syndrome. Am J Gastroenterol. 2021 Jan 1;116(1):17-44.Full text Abstract
Smalley W, Falck-Ytter C, Carrasco-Labra A, et al. AGA clinical practice guidelines on the laboratory evaluation of functional diarrhea and diarrhea-predominant irritable bowel syndrome in adults (IBS-D). Gastroenterology. 2019 Sep;157(3):851-4.Full text Abstract
Chey WD, Hashash JG, Manning L, et al. AGA clinical practice update on the role of diet in irritable bowel syndrome: expert review. Gastroenterology. 2022 May;162(6):1737-45.e5.Full text Abstract
Dionne J, Ford AC, Yuan Y, et al. A systematic review and meta-analysis evaluating the efficacy of a gluten-free diet and a low FODMAPs diet in treating symptoms of irritable bowel syndrome. Am J Gastroenterol. 2018 Sep;113(9):1290-300. Abstract
Chang L, Sultan S, Lembo A, et al. AGA clinical practice guideline on the pharmacological management of irritable bowel syndrome with constipation. Gastroenterology. 2022 Jul;163(1):118-36.Full text Abstract
Lembo A, Sultan S, Chang L, et al. AGA clinical practice guideline on the pharmacological management of irritable bowel syndrome with diarrhea. Gastroenterology. 2022 Jul;163(1):137-51.Full text Abstract
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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