Contents

Search

irritable bowel syndrome (IBS)

A functional intestinal disorder associated with pain, alterations in pattern of defecation &/or bloat & distension. Classification: 1) IBS with constipation (IBS-C) a) hard or lumpy stools > 25% b) loose or watery stools < 25% 2) IBS with diarrhea (IBS-D) a) hard or lumpy stools < 25% b) loose or watery stools > 25% 3) mixed IBS (IBS-M) a) hard or lumpy stools > 25% b) loose or watery stools > 25% 4) unsubtyped IBS (IBS-U) - stool consistency does not meet criteria for IBS-C, IBS-D or IBS-M [2] Etiology: 1) inconclusive relationship with psychiatric disorders - depression, anxiety, psychosocial stress - somatoform disorders - post-traumatic stress disorder 2) patients with psychiatric disorders are more likely to seek medical attention 3) antibiotics (single course) may predispose to IBS [4] 4) indigested carbohydrates a) fructose malabsorption (40%) b) fructose & fructans can ellicit symptoms [10] 5) gluten sensitivity may play a role in some patients [19] 6) may be triggered by an episode of acute gastroenteritis [44] 7) other disease associations - functional dyspepsia - GERD - cyclic vomiting syndrome - gastroparesis - fibromyalgia - headache - chronic pelvic pain - interstitial cystitis - dysmenorrhea - sexual dysfunction [2] Epidemiology: 1) prevalence is 15-20% in Western countries - prevalence is 7-16% in U.S. [29] 2) most individuals do not seek medical help 3) 75% of patients in Western nations who seek medical help are female 4) 25-50% of all outpatient referrals to gastroenterology 5) commonly affects women age 20-40 years [2] Pathology: 1) dysfunction small intestinal smooth muscle response to: - stress, meals, peptides 2) pain occurs secondary to intestinal hypermotility 3) reduced sensory threshold for intestinal & rectal distension 4) postulated mechanisms: a) abnormal gastrointestinal motility b) visceral afferent hypersensitivity with central sensitization c) altered activation of the mucosal immune system d) cytolethal distending toxin B from Campylobacter jejuni may play a role [26] - cytolethal distending toxin B antibody may cross- react with host epithelial vinculin [26] Clinical manifestations: 1) usually begins in young adulthood [12] 2) continuous or recurrent symptoms for at least 3 months a) abdominal pain or discomfort relieved by defecation or passing gas b) alternating diarrhea & constipation 1] altered stool frequency 2] altered stool consistency - hard, loose, watery 3] altered stool passage a] straining or urgency b] feeling of incomplete evacuation c) passage of mucus d) bloat or abdominal distension e) symptoms do NOT awaken the patient from sleep 3) physical examination is generally normal a) umbilical or epigastric tenderness may accompany small bowel involvement c) tenderness over area of spastic colon may occur 4) patients frequently have a history of multiple problems, especially allergies, headaches, arthralgias, kidney disease, dysparunia 5) indications 'red flags' of a more serious disorder: a) weight loss b) bloody stools c) nocturnal symptoms (bowel movements) d) recent antibiotic use e) symptom onset > 50 years of age f) fever [2] Diagnosis: - see Rome criteria [2] - reucrrent abdominal pain at least 1 day/week for 3 months - 2 of the following - defecation-related pain - change in stool frequency - change in stool consistency [2] - most patients with typical IBS symptoms without bleeding, weight loss or family history of colon cancer, inflammatory bowel disease or celiac sprue, do not need further diagnostic testing [12] - IBS patients with diarrhea or a mixture of diarrhea & constipation should be screened with blood tests for celiac disease [12] - when patients with IBS & diarrhea undergo colonoscopy, biopsy to rule out microscopic colitis [12] * rule out celiac disease prior to diagnosis of irritable bowel syndrome [8] Laboratory: 1) routine laboratory testing not indicated in the absence of 'red flags' 2) complete blood count (CBC): generally within normal limits 3) erythrocyte sedimentation rate (ESR): generally within normal limits 4) stool specimen: a) only fecal occult blood testing indicated for patients who meet Rome criteria [2] b) giardia antigen in stool [33] - leukocytes, blood, culture, ova & parasites if travel history c) bile acids in stool (optional) [33] d) Sudan black stain for fecal fat - negative findings 5) urinalysis to exclude urinary cause of symptoms 6) chemistry panel - serum TSH if diarrhea 7) testing for celiac disease* [2,20] if diarrhea - tissue transglutaminase IgA in serum - tissue transglutaminase IgG in serum if IgA deficient [33] - test for celiac disease even if intermittent constipation 8) lactose H2 breath test for suspected lactose intolerance 9) screen for inflammatory bowel disease [33] - fecal calprotectin (threshold 50 ug/g) - fecal lactoferrin (threshold 4-7 ug/g) to - C-reactive protein in serum only if above 2 tests unavailable 10) low levels of food-specific serum IgE, esp wheat IgE Ab in serum & soy IgE Ab in serum 11) serum 25-OH vitamin D [45] (see management) 12) investigational - cytolethal distending toxin B antibody [33] - cytolethal distending toxin B gene (Loinc: 53943-7) - vinculin antibody [26,33] * rule out celiac disease prior to diagnosis of irritable bowel syndrome [36] Special laboratory: 1) flexible sigmoidoscopy with colonic biopsy a) indications 1] suspicion of inflammatory bowel disease 2] red flags or alarm features (see clinical manifestations) 3] patients who do not meet strict criteria for IBS [2] 4] test for tissue transglutaminase IgA 1st [2] b) air sufflation during sigmoidoscopy often reproduces symptoms c) not indicated for diagnosis [2] 2) colonoscopy a) patients over age 45-50 b) recommended for severe or refractory symptoms [2] c) biopsy to rule out microscopic colitis d) not indicated for diagnosis [2] Radiology: - plain abdominal radiograph if bloating or distension - avoid computed tomography in the absence of red flags [2] Complications: - unnecessary surgery [6] Differential diagnosis: 1) colorectal carcinoma 2) inflammatory bowel disease 3) infectious colitis 4) diverticulitis 5) mesenteric ischemia 6) diarrhea as predominant symptom a) lactase deficiency b) laxative abuse c) malabsorption - celiac disease* d) FODMAP sensitivity e) hyperthyroidism 7) constipation as predominant symptom a) hypercalcemia b) hypothyroidism c) adverse effects of medications 8) epigastric & periumbilical pain a) peptic ulcer disease b) gastritis c) cholecystitis d) pancreatitis e) functional dyspepsia * watch for celiac disease - red flags will be present [2] - screening not routinely incidated [16] Management: 1) constipation a) water soluble fiber: [11] start psyllium 1 tbsp BID - number needed to treat - 7 [23] b) osmotic laxative (polyethylene glycol) c) stool softener: docusate (Colace) 100 mg BID d) lubiprostone, a chloride channel activator, benefits a subset of women with IBS & constipation [2,21,25] e) linaclotide effective [25] (treatment of choice in refractory IBS-C) [36,37,38] f) plecanatide [2] g) tenapanor reduces abdominal pain, discomfort, bloating, cramping,& fullnes h) exercise 2) diarrhea a) trial of reduced lactose intake (< 8 oz or 240 mL of milk) b) low FODMAP diet [2] - low FODMAP diet superior to antispasmodic treatment [35] c) antispasmodic agents [11,25] 1] belladona 2] dicyclomine (Bentyl) d) antidiarrheal agents 1] loperamide (Imodium) 2-4 mg every 6-8 hours 2] diphenoxylate (Lomotil) 2.5-5 mg every 4-6 hours e) fiber f) tricyclic antidepressant as second line treatment [2,12,25,39,41] - amitriptyline safe, well tolerated, effective [41] g) probiotics may be of benefit [12,24] - number need to treat = 7 [24] - results inconsistent (MKSAP19) [2] h) alosetron withdrawn from U.S. market due to ischemic colitis [2,12,25] i) rifaximin may be effective [25] j) eluxadoline for IBS with diarrhea [27] k) fecal transplantation [30] - no more effective than placebo in the treatment of IBS (MKSAP19) [2,40] 3) bloat a) anticholinergics (1st line) [2] 1] dicyclomine (Bentyl) 10-30 mg 30 min before meals - can cause constipation, rarely used with IBS-C [36] 2] hyoscyamine b) antidepressants: (adjunct therapy) begin at lower dose 1] tricyclic antidepressant may be helpful a] amitriptyline (Elavil) 25-150 mg QHS b] doxepin (Sinequan) 25-150 mg QHS c] can cause constipation, rarely used with IBS-C [36] 2] serotonin re-uptake inhibitor (SSRI) a] fluoxetine (Prozac) 20 mg QD b] paroxetine (Paxil) [5]: start 10 mg QD; titrate up to 40 mg QD c] insufficient evidence of benefit [25] d) prokinetic agents: 1] cisapride (Propulsid) 10-20 mg BID (withdrawn by FDA) 2] metoclopramide (Reglan) e) rifaximin (Xifaxan) has been found to be of benefit for selected patients, especially those with bloating & diarrhea [12,14] 4) proton-pump inhibitors or H2 blockers may benefit patients with diarrhea & urgency after meals [3] - benefits should become apparent within 3 days 5) complementary or alternative medicine a) herbal therapy, dietary supplements, & mind-body therapy helpful for overall response.[34] b) ony herbal therapy helpful for abdominal pain 6) probiotics may be of some benefit a) Bifidobacter infantis offers benefit to some patients with IBS & diarrhea [12] b) Lactobacillus may be of benefit [4] c) Lactobacillus GG not helpful in children [7]; reduces frequency & severity of abdominal pain in children [15] 7) peppermint oil may be of benefit [11] 8) adjunctive cognitive behavior therapy may be helpful [8] - symptom improvement after home-based or clinic-based CBT sustained for at least 1 year [31] 9) melatonin 3 mg QHS may be helpful [9] 10) patient education a) stress may precipitate attacks b) disorder is chronic, but without serious sequelae 11) dietary management may be helpful: [12] a) avoid or limit the amount of gas-producing foods - beans, onions, broccoli, cabbage b) avoid other foods that aggravate IBS symptoms c) eat slowly c) avoid overeating d) avoid carbonated drinks e) avoid lactose (lactose intolerance in 40% of IBS) f) avoid large quantities of fructose or sorbitol g) insoluble fiber (psyllium, wheat bran) may be of benefit - number needed to treat - 7 [23] h) some patients improve on a wheat (gluten)-free diet [18,20] - evidence for use in patients with IBS-D is inconclusive (MKSAP19) [2] i) low FODMAP diet may be of benefit [28] j) microbiome-based AI-assisted personalized diet not different from low-FODMAP diet [43] 12) IB-stim is an FDA-approved TENS device for IBS placed behind the ear [32] 13) vitamin D supplementation may improve quality of life in adults with irritable bowel syndrome (IBS) & vitamin D deficiency [45] 14) up to 30% of patients resort to alternative medicine Notes: - may be a genetic predisposition to respond to placebo [17]

Interactions

disease interactions

Related

FODMAP (Fermentable, Oligo-, Di-, Monosaccharides, & Polyols) functional dyspepsia Rome criteria for irritable bowel syndrome

General

intestinal disease chronic gastrointestinal disease

References

  1. Saunders Manual of Medical Practice, Rakel (ed), WB Saunders, Philadelphia, 1996, pg 347-49
  2. Medical Knowledge Self Assessment Program (MKSAP) 11, 14, 15, 16, 17, 18, 19. American College of Physicians, Philadelphia 1998, 2006, 2009, 2012, 2015, 2018, 2021. - Medical Knowledge Self Assessment Program (MKSAP) 19 Board Basics. An Enhancement to MKSAP19. American College of Physicians, Philadelphia 2022
  3. Prescriber's Letter 8(8):43-44, 2001
  4. Journal Watch 22(4):29, 2002 Maxwell PR et al, Antibiotics increase functional abdominal symptoms. Gastroenterol 97:104, 2002 PMID: 11808932 - Nobaek S et al Alteration of intestinal microflora is associated with reduction in abdominal bloating and pain in patients with irritable bowel syndrome. Am J Gastroenterol 95:1231, 2000 PMID: 10811333
  5. Prescriber's Letter 9(12):71 2002
  6. Journal Watch 24(15):123, 2004
    1. Longstreth GF, Yao JF. Irritable bowel syndrome and surgery: a multivariable analysis. Gastroenterology. 2004 Jun;126(7):1665-73. PMID: 15188159 - Talley NJ. Unnecessary abdominal and back surgery in irritable bowel syndrome: time to stem the flood now? Gastroenterology. 2004 Jun;126(7):1899-903. Review. No abstract available. PMID: 15188187
  7. Bausserman M, Michail S. The use of Lactobacillus GG in irritable bowel syndrome in children: a double-blind randomized control trial. J Pediatr. 2005 Aug;147(2):197-201. PMID: 16126049
  8. Kennedy T, Jones R, Darnley S, Seed P, Wessely S, Chalder T. Cognitive behaviour therapy in addition to antispasmodic treatment for irritable bowel syndrome in primary care: randomised controlled trial. BMJ. 2005 Aug 20;331(7514):435. Epub 2005 Aug 10. PMID: 16093252
  9. Lu WZ, Gwee KA, Moochhalla S, Ho KY. Melatonin improves bowel symptoms in female patients with irritable bowel syndrome: a double-blind placebo-controlled study. Aliment Pharmacol Ther. 2005 Nov 15;22(10):927-34. PMID: 16268966 - Song GH, Leng PH, Gwee KA, Moochhala SM, Ho KY. Melatonin improves abdominal pain in irritable bowel syndrome patients who have sleep disturbances: a randomised, double blind, placebo controlled study. Gut. 2005 Oct;54(10):1402-7. Epub 2005 May 24. PMID: 15914575 - Elsenbruch S. Melatonin: a novel treatment for IBS? Gut. 2005 Oct;54(10):1353-4. No abstract available. PMID: 16162946
  10. Shepherd SJ et al. Dietary triggers of abdominal symptoms in patients with irritable bowel syndrome: Randomized placebo-controlled evidence. Clin Gastroenterol Hepatol 2008 Jul; 6:765. PMID: 18456565
  11. Ford AC et al. Effect of fibre, antispasmodics, and peppermint oil in the treatment of irritable bowel syndrome: Systematic review and meta-analysis. BMJ 2008 Nov 13; 337:a2313. http://dx.doi.org/10.1136/bmj.a2313 PMID: 19008265
  12. University of Michigan Health System, News Release New recommendations released for treatment of IBS Dec 19, 2008 http://www2.med.umich.edu/prmc/media/newsroom/details.cfm?ID=945 - Full list of 2008 IBS guidelines http://www.nature.com/ajg/journal/v104/n1s/index.html/.
  13. Prescriber's Letter 16(5) 2009 Treatments for Irritable Bowel Syndrome (IBS) PATIENT HANDOUT: Managing Irritable Bowel Syndrome (IBS) COMMENTARY: Treatments for Irritable Bowel Syndrome (IBS) GUIDELINES: Evidence-Based Position Statement on the Management of Irritable Bowel Syndrome by the American College of Gastroenterology Detail-Document#: 250504 (subscription needed) http://www.prescribersletter.com - An Evidence-Based Systematic Review on the Management of Irritable Bowel Syndrome American College of Gastroenterology Task Force on IBS http://www.nature.com/ajg/journal/v104/n1s/pdf/ajg2008122a.pdf
  14. Pimentel M et al Rifaximin Therapy for Patients with Irritable Bowel Syndrome without Constipation N Engl J Med 2011; 364:22-32. January 6, 2011 PMID: 21208106 http://www.nejm.org/doi/full/10.1056/NEJMoa1004409 - Tack J Antibiotic Therapy for the Irritable Bowel Syndrome PMID: 21208112 http://www.nejm.org/doi/full/10.1056/NEJMe1011211
  15. Francavilla R et al. A randomized controlled trial of Lactobacillus GG in children with functional abdominal pain. Pediatrics 2010 Dec; 126:e1445. PMID: 21078735
  16. Cash BD et al. The prevalence of celiac disease among patients with nonconstipated irritable bowel syndrome is similar to controls. Gastroenterology 2011 Oct; 141:1187 PMID: 21762658
  17. Hall KT et al. Catechol-O-methyltransferase val158met polymorphism predicts placebo effect in irritable bowel syndrome. PLoS ONE 2012 Oct 23; 7:e48135. PMID: 23110189
  18. Carroccio A et al. Non-celiac wheat sensitivity diagnosed by double-blind placebo-controlled challenge: Exploring a new clinical entity. Am J Gastroenterol 2012 Dec; 107:1898. PMID: 22825366 - Sanders DS and Aziz I. Non-celiac wheat sensitivity: Separating the wheat from the chat! Am J Gastroenterol 2012 Dec; 107:1908. PMID: 23211856
  19. Vazquez-Roque MI et al. A controlled trial of gluten-free diet in patients with irritable bowel syndrome-diarrhea: Effects on bowel frequency and intestinal function. Gastroenterology 2013 May; 144:903 PMID: 23357715
  20. Ford AC, Chey WD, Talley NJ et al Yield of diagnostic tests for celiac disease in individuals with symptoms suggestive of irritable bowel syndrome: systematic review and meta-analysis. Arch Intern Med. 2009 Apr 13;169(7):651-8 PMID: 19364994
  21. Drossman DA, Chey WD, Johanson JF et al Clinical trial: lubiprostone in patients with constipation- associated irritable bowel syndrome--results of two randomized, placebo-controlled studies. Aliment Pharmacol Ther. 2009 Feb 1;29(3):329-41 PMID: 19006537
  22. American College of Gastroenterology Task Force on Irritable Bowel Syndrome, Brandt LJ, Chey WD, Foxx-Orenstein AE et al An evidence-based position statement on the management of irritable bowel syndrome. Am J Gastroenterol. 2009 Jan;104 Suppl 1:S1-35 PMID: 19521341
  23. Moayyedi P et al. The effect of fiber supplementation on irritable bowel syndrome: A systematic review and meta-analysis. Am J Gastroenterol 2014 Sep; 109:1367. PMID: 25070054
  24. Ford AC et al. Efficacy of prebiotics, probiotics, and synbiotics in irritable bowel syndrome and chronic idiopathic constipation: Systematic review and meta-analysis. Am J Gastroenterol 2014 Oct; 109:1547 PMID: 25070051
  25. Weinberg DS et al. American Gastroenterological Association Institute guideline on the pharmacological management of irritable bowel syndrome. Gastroenterology 2014 Nov; 147:1146 PMID: 25224526
  26. Pimentel M et al. Development and validation of a biomarker for diarrhea- predominant irritable bowel syndrome in human subjects. PLoS ONE 2015 May 13; 10:e0126438 PMID: 25970536
  27. Lembo AJ, Lacy BE, Zuckerman MJ et al Eluxadoline for Irritable Bowel Syndrome with Diarrhea. N Engl J Med 2016; 374:242-253. January 21, 2016 PMID: 26789872 http://www.nejm.org/doi/full/10.1056/NEJMoa1505180
  28. Eswaran SL et al. A randomized controlled trial comparing the low FODMAP diet vs. modified NICE guidelines in US adults with IBS-D. Am J Gastroenterol 2016 Dec; 111:1824 PMID: 27725652
  29. Rothaus C Irritable Bowel Syndrome NEJM Resident 360. June 28, 2017 https://resident360.nejm.org/content_items/irritable-bowel-syndrome/
  30. Johnsen PH, Hilpusch F, Cavanagh JP et al Faecal microbiota transplantation versus placebo for moderate- to-severe irritable bowel syndrome: a double-blind, randomised, placebo-controlled, parallel-group, single-centre trial. Lancet Gastroenterology and Hepatology Oct 31, 2017 PMID: 29100842 http://thelancet.com/journals/langas/article/PIIS2468-1253(17)30338-2/fulltext - Ford AC Stool as a treatment for IBS: more questions than answers? Lancet Gastroenterology and Hepatology Oct 31, 2017 PMID: 29100844 http://thelancet.com/journals/langas/article/PIIS2468-1253(17)30337-0/fulltext
  31. Lackner JM, Jaccard J, Radziwon CD et al. Durability and decay of treatment benefit of cognitive behavioral therapy for irritable bowel syndrome: 12-month follow-up. Am J Gastroenterol 2018 Nov 14; PMID: 30429592 https://www.nature.com/articles/s41395-018-0396-x
  32. FDA News Release. June 7, 2019 FDA permits marketing of first medical device for relief of pain associated with irritable bowel syndrome in patients 11-18 years of age. https://www.fda.gov/news-events/press-announcements/fda-permits-marketing-first-medical-device-relief-pain-associated-irritable-bowel-syndrome-patients
  33. Smalley W, Falck-Ytter C, Carrasco-Labra A et al. AGA guideline on the laboratory evaluation of functional diarrhea and diarrhea-predominant irritable bowel syndrome in adults (IBS-D). Gastroenterology 2019 Jul 11; PMID: 31377275 https://www.gastrojournal.org/article/S0016-5085(19)41083-4/fulltext
  34. Billings W, Mathur K, Craven HJ et al. Potential benefit with complementary and alternative medicine in irritable bowel syndrome: A systematic review and meta-analysis. Clin Gastroenterol Hepatol 2020 Sep 19; PMID: 32961342 https://www.cghjournal.org/article/S1542-3565(20)31296-9/pdf
  35. Carbone F et al. Diet or medication in primary care patients with IBS: The DOMINO study - a randomised trial supported by the Belgian Health Care Knowledge Centre (KCE Trials Programme) and the Rome Foundation Research Institute. Gut 2022 Nov; 71:2226. PMID: 35483886 PMCID: PMC9554021 Free PMC article https://gut.bmj.com/content/71/11/2226
  36. NEJM Knowledge+ Gastroenterology
  37. 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. PMID: 33315591
  38. Chang L, Sultan S, Lembo A, et al. AGA clinical practice guideline on the pharmacological management of irritable bowel syndrome with constipation. Gastroenterology. 2022;163:118-136. PMID: 35738724
  39. Camilleri M. Diagnosis and treatment of irritable bowel syndrome: a review. JAMA. 2021;325:865-877. PMID: 33651094
  40. Myneedu K, Deoker A, Schmulson MJ, Bashashati M. Fecal microbiota transplantation in irritable bowel syndrome: A systematic review and meta-analysis. United European Gastroenterol J. 2019 Oct;7(8):1033-1041. PMID: 31662860 PMCID: PMC6794695 Free PMC article.
  41. Ford AC et al Amitriptyline at Low-Dose and Titrated for Irritable Bowel Syndrome as Second- Line Treatment in primary care (ATLANTIS): a randomised, double-blind, placebo- controlled, phase 3 trial. Lancet. 2023. Oct 16 https://www.thelancet.com/journals/lancet/article/PIIS0140-6736(23)01523-4/fulltext
  42. Lembo AJ, Chey WD, Harris LA et al. Abdominal Symptom Improvement During Clinical Trials of Tenapanor in Patients With Irritable Bowel Syndrome With Constipation: A Post Hoc Analysis. Am J Gastroenterol. 2024 Mar 15 PMID: 38294158 https://journals.lww.com/ajg/fulltext/9900/abdominal_symptom_improvement_during_clinical.1000.aspx
  43. Tunali V, Arslan NC, Ermis BH, et al. A Multicenter Randomized Controlled Trial of Microbiome-Based Artificial Intelligence-Assisted Personalized Diet vs Low-Fermentable Oligosaccharides, Disaccharides, Monosaccharides, and Polyols Diet: A Novel Approach for the Management of Irritable Bowel Syndrome. Am J Gastroenterol. 2024 May 8. PMID: 38717025
  44. Porcari S, Ingrosso MR, Maida M et al. Prevalence of irritable bowel syndrome and functional dyspepsia after acute gastroenteritis: Systematic review and meta-analysis. Gut 2024 Aug 8; 73:1431-1440 PMID: 39013599 https://gut.bmj.com/content/73/9/1431
  45. Cara KC, Taylor SF, Alhmly HF et al The effects of vitamin D intake and status on symptom severity and quality-of-life in adults with irritable bowel syndrome (IBS): a systematic review and meta-analysis. Critical Reviews in Food Science and Nutrition. 2024 1-14 https://www.tandfonline.com/doi/epdf/10.1080/10408398.2024.2400603
  46. National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) Irritable Bowel Syndrome https://www.niddk.nih.gov/health-information/digestive-diseases/irritable-bowel-syndrome