Community Acquired Acute Gastrointestinal Infection ( including Food Poisoning ) in Adults Seen in Accident and Emergency and/or Requiring Hospital Admission - Guideline for the Management of

Publication: 01/01/2008  
Next review: 20/01/2025  
Clinical Guideline
ID: 1211 
Approved By: Improving Antimicrobial Prescribing Group 
Copyright© Leeds Teaching Hospitals NHS Trust 2022  


This Clinical Guideline is intended for use by healthcare professionals within Leeds unless otherwise stated.
For healthcare professionals in other trusts, please ensure that you consult relevant local and national guidance.


  • Diagnostics
  • Non-antimicrobial management
  • Empirical treatment
  • Review by 72
  • Directed therapy

  • Acute gastroenteritis is an illness of <14 days duration characterised by the presence of diarrhoea (3 or more loose stools per day or bloody stools).
  • Accompanying symptoms may include abdominal pain/cramps, nausea, vomiting and fever.
  • Causes included a wide range of bacterial (e.g. Campylobacter spp., Salmonella spp., certain strains of Escherichia coli), viral and protozoal pathogens.
  • The history should identify pre-existing medical conditions that increase the risk of an adverse outcome (e.g. immunosuppression).
  • It is also important to ascertain the potential source of the infection by asking about travel history, contact with a similar illness affecting others and possible food sources.
  • C.difficile infection should be considered in patients where risk factors are present (click here).
  • As the symptoms/signs of gastroenteritis are nonspecific, alternative diagnoses should also be considered.
  • The majority of patients with acute gastroenteritis DO NOT require antimicrobial treatment as the illness will be self-limiting and without sequelae
  • Certain Shigella and E.coli infections (e.g. E.coli O157) can be complicated by Haemolytic-Uraemic syndrome (HUS). The clinical features are non-specific (unless Thrombotic Thrombocytopenic Purpura (TTP) is present) and can follow resolution of gastroenteritis.

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For patients with a presumed diagnosis of community acquired acute gastrointestinal infection (including food poisoning) the following diagnostic tests should be taken to confirm diagnosis:
Include pertinent clinical details on the request form, e.g. travel history/possible food source. Note that in the absence of clinical details the sample will not be processed.

All patients


Stool sample for bacterial cultures (MC&S)
For patients who are being discharged (e.g. from A&E or admissions units) supply a faeces collection container and advise them to deliver a sample to their GP at the earliest opportunity.

Stool sampling for enteric virus PCR should be performed in patients who are hospitalised, the immunocompromised, and when cases may be part of an outbreak.

If Haemolytic uraemic syndrome (HUS) is suspected

Blood film
Haemolysis screen
These cases should be discussed with Microbiology/Infectious Diseases.

If abdominal pain/distention

Consider abdominal radiograph.
An erect chest radiograph should be performed if there is evidence of peritonism.

If immunocompromised or potentially part of an outbreak

Stool sampling for enteric virus PCR should be performed in patients who are hospitalised, the immunocompromised, and when cases may be part of an outbreak.

If patient is immunocompromised, recent foreign travel or symptoms present >2 weeks, and/or concerns about Enteric fever

3 stool samples may be sent for ova, cyst and parasite (OCP) examination
These cases should be discussed with Microbiology/Infectious Diseases.

Risk factors for Clostridium difficle

Request toxin testing if the patient has any risk factors for Clostridium difficile infection (CDI; see history section).

If showing signs of sepsis

Blood cultures - if showing signs of sepsis or enteric fever (typhoid or paratyphoid) suspected
Check other electrolytes if indicated.

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  • Ensure adequate rehydration using either oral fluids if tolerated, or intravenous fluids.
  • Do not use anti-diarrhoeals as they may worsen acute gastroenteritis and its complications.

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Doses assume normal renal and hepatic function.
The majority of patients with acute gastroenteritis DO NOT require antimicrobial treatment as the illness will be self-limiting and without sequelae

Empirical options for community acquired acute gastrointestinal infection (including food poisoning)




Treatment not recommended

Moderate severity

Treatment not recommended

Where IV antibiotics are indicated blood cultures should be sent before initiating treatment.

Severe (IV required)

Refer to Intra-abdominal Infection guideline

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By 72 hours of antimicrobial treatment, diagnostics should have proven your initial diagnosis or guided to a new diagnosis.

If your patient in on IV treatment this should be reviewed daily.

The review, outcome and future plans (where appropriate) should be documented in the medical notes.

If the diagnosis is still correct your options are now:


If your initial diagnosis is correct and the patient is prescribed IV antibiotics, review whether an oral switch is appropriate using the ACED criteria (see below). If they meet all 4 criteria (community acquired acute gastrointestinal infection (including food poisoning) is not a deep seated infection) consider switching using the oral options listed in the table above. 
A - Afebrile for 24 hours
C - Clinically improving
E - Eating and drinking
D - not Deep seated infection


If no signs of infection and diagnostics support this decision.


If the patient is not clinically responding, check microbiology results to see if directed therapy is required or you may need to consider an alternative diagnosis.


If the patient is improving but does not fully meet ACED criteria. Review daily until ready to switch. Document the reason for continuing.

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1st line

2nd line


The choice of step-down antibiotic should be guided by sensitivities.


Campylobacter 1

Clarithromycin electronic Medicines Compendium information on Clarithromycin PO 500mg 12-hourly

Ciprofloxacin electronic Medicines Compendium information on Ciprofloxacin PO 500mg 12-hourly

5 days

Clostrium difficile 1

Refer to separate guideline

E coli O157 (and other verotoxin producing strains) 1

Discuss with microbiology or infectious diseases

Salmonella (except enteric fever) 1

Ciprofloxacin electronic Medicines Compendium information on Ciprofloxacin PO 500mg 12-hourly
Duration: 5 days

If history of travel to SE Asia/Indian subcontinent or possible/confirmed Salmonella Typhi/Paratyphi discuss urgently with infectious diseases

Discuss with microbiology or infectious diseases

5 days

Shigella 1

Ciprofloxacin electronic Medicines Compendium information on Ciprofloxacin PO 500mg 12-hourly
Duration: 5 days
(NB no antibiotics if associated HUS - discuss with microbiology or infectious diseases)

Azithromycin electronic Medicines Compendium information on Azithromycin PO 500mg 12-hourly
Duration: 3 days
Sensitivities not routinely performed for azithromycin - contact microbiology if prescribing azithromycin

Yersinia enterocolitica

Treatment not usually indicated, but contact ID/Microbiology if severe or patient has risk factors.


Treatment not usually recommended.


Treatment not usually recommended.
If severe/immunocompromised discuss with microbiology or infectious diseases

Enteric viruses (e.g. Norovirus)

Treatment not usually recommended.


  1. Organisms associated with bloody stools (dysentery). Entamoeba histolytica also indicated.


Record: 1211
Clinical condition:

Acute gastroenteritis (including food poisoning) in adult patients

Target patient group: Adults patients seen in Accident and Emergency and all those admitted to hospital
Target professional group(s): Pharmacists
Secondary Care Doctors
Adapted from:

Evidence base

  1. Diarrhoeal disease. Fact sheet 330. WHO; August 2009. Available at:
  2. Heath Protection Agency. (2011). Campylobacter cases in England and Wales, 1989-2010. Available at Accessed 01/12/2011.
  3. Health Protection Agency. Salmonella cases by serotype. (2011).
  4. DuPont HL. Travellers' diarrhoea: contemporary approaches to therapy and prevention. Drugs. 2006;66:303-14.
  5. Behravesh C, Jones T, Vugia D et al. Deaths associated with bacterial pathogens transmitted commonly through food: foodborne diseases active surveillance network (FOODNET). J Infect Dis. 2011;204:263-267.
  6. Manatsathit S, Dupont H, Farthing M et al. Guideline for the management of acute diarrhea in adults. J Gastroenterol Hepatol. 2002;17(Suppl):S54-S71.
  7. Guerrant RL et al. Practice guidelines for the management of infectious diarrhea. Clin Infect Dis. 2001;32:331-351.
  8. Farthing M, Feldman R, Finch R et al. The management of infective gastroenteritis in adults. A consensus statement by an expert panel convened by the British Society for the Study of Infection. J Infect. 1996;33:143-152.
  9. Clinical Knowledge Summary. Gastroenteritis. 
  10. Tam C et al. The Second Study of Infectious Intestinal Disease in the Community (IID2 Study). 2011. Available at: Accessed 22/11/2011.
  11. Thielman N, Guerrant R. Acute Infectious Diarrhea. New Engl J Med. 2004;350:38-47.
  12. Farthing et al. World Gastroenterology Organisation practice guideline: acute diarrhoea. 2008. 
  13. DuPont HL, Hornick RB. Adverse effect of lomotil therapy in shigellosis. JAMA. 1973;226:1525-8.
  14. Cimolai N, Basalyga S, Mah D, Mirrison B, Carter J. A continuing assessment of risk factors for the development of Escherichia coli 0157:H7-associated haemolytic uremic syndrome. Clin Nephrol. 1994;42:85-9.
  15. Goodman G, Trenholme G, Kaplan R et al. Empiric antimicrobial therapy for domestically acquired acute diarrhea in urban adults. Arch Intern Med. 1990;150:541-6.
  16. Dryden M, Gabb R, Wright . Empirical treatment of severe acute community-acquired gastroenteritis with Ciprofloxacin electronic Medicines Compendium information on CiprofloxacinClin Infect Dis. 1996;22:1019-25.
  17. Wistronm J, Jertborn M, Ewall E et al. Empiric treatment of acute diarrheal disease with norfloxacin. A randomized, placebo-controlled study. Swedish study group. Ann Intern Med. 1993;117:202-8.
  18. Sirinavin S, Garner P. Antibiotics for treating salmonella gut infections. Cochrane Database Syst Rev. 2000;(2):CD001167. Available at: Accessed 28/11/2011.
  19. Wong C, Jelacic S, Habeeb R, Watkins S, Tarr P. The risk of haemolytic-uremic syndrome after antibiotic threatment of Escherichia coli 0157:H7 infections. N Engl J Med. 2000;342:1930-6.
  20. Zhang X, McDaniel A, Wolf L, Keusch G, Waldor M, Acheson D. Quinolone antibiotics induce shiga-toxin encoding bacteriophages, toxin production, and death in mice. J Infect Dis. 2000;181:664-70.
  21. Safdar N, Said A, Gangnn R, Maki D. Risk of haemolytic uremic syndrome after antibiotic treatment of Escherichia coli O157:H7 enteritis: a meta-analysis. JAMA. 2002;288:996-1001.
  22. Health Protection Agency. (2011). Shigella spp. laboratory reports of faecal isolates reported to the Health Protection Agency Centre for Infections England and Wales, 1992-2010. 
  23. DuPont, H.L. (2010). Chapter 221: Shigella species (bacillary dysentery). In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th edn. Elsevier: Philadelphia.
  24. White AC. (2010). Chapter 283: Cryptosporidium species. In: Mandell, Douglas, and Bennett's Principles and Practice of Infectious Diseases. 7th edn. Elsevier: Philadelphia.
  25. Public Health England (2013).  UK One Health Report: Joint report on human and animal antibiotic use, sales and resistance.  PHE publications gateway number: 2015160
  26. Gastroenteritis. Clinical knowledge summaries, NICE.
  27. Shane AL, Mody RK, Crump JA, Tarr PI, Steiner TS, Kotloff K, Langley JM, Wanke C, Warren CA, Cheng AC, Cantey J, Pickering LK. 2017 Infectious Diseases Society of America Clinical Practice Guidelines for the Diagnosis and Management of Infectious Diarrhea. Clin Infect Dis. 2017 Nov 29;65(12):e45-e80
  28. Riddle MS, DuPont HL, Connor BA. ACG Clinical Guideline: Diagnosis, Treatment, and Prevention of Acute Diarrheal Infections in Adults. Am J Gastroenterol. 2016 May;111(5):602-22. doi: 10.1038/ajg.2016.126. Epub 2016 Apr 12. PMID: 27068718.

Approved By

Improving Antimicrobial Prescribing Group

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