Shigella infection

Last reviewed: 23 Aug 2023
Last updated: 03 Feb 2021



History and exam

Key diagnostic factors

  • diarrhea
  • cramping abdominal pain
  • fever
  • features of hemolytic uremic syndrome
More key diagnostic factors

Other diagnostic factors

  • tenesmus
  • abdominal pain or tenderness
  • signs of volume depletion
  • increased bowel sounds
  • vomiting
  • meningismus
  • febrile seizures
  • delirium or somnolence
Other diagnostic factors

Risk factors

  • exposure to contaminated water or food or direct fecal-oral contact
  • age <5 years
  • age >50 years
  • malnutrition
  • poor hygiene and cramped conditions
  • chronic illness or immunocompromise
  • travel to endemic areas
  • men who have sex with men
More risk factors

Diagnostic investigations

1st investigations to order

  • stool microscopy, culture, and sensitivity
  • serum BUN and creatinine
  • CBC
More 1st investigations to order

Investigations to consider

  • Shigella serotyping
  • peripheral blood smear
  • abdominal x-ray
  • flexible sigmoidoscopy
More investigations to consider

Treatment algorithm


suspected or confirmed shigellosis



Ashley Barnabas, MRCP

Consultant Hepatologist and Gastroenterologist

St Mark's and Northwick Park Hospitals




AB declares that he has no competing interests.


Dr Ashley Barnabas would like to gratefully acknowledge Dr Satish Keshav, Dr Gehanjali D.A. Amarasinghe, and Dr Richard Pollok, the previous contributors to this topic. Unfortunately, we have been made aware that Dr Satish Keshav has passed away.


GDAA and RP declare that they have no competing interests.

Peer reviewers

David Acheson, MD

Chief Medical Officer

Director of Food Safety and Security

US Food and Drug Administration




DA declares that he has no competing interests.

Franz Allerberger, MD, MPH

Professor of Clinical Microbiology

Austrian Agency for Health and Food Safety (AGES)




FA declares that he has no competing interests.

  • Shigella infection images
  • Differentials

    • Non-Shigella bacterial diarrhea
    • Viral gastroenteritis
    • Parasitic diarrhea
    More Differentials
  • Guidelines

    • CDC health information for international travel (yellow book) - shigellosis
    • Practice guidelines for the diagnosis and management of infectious diarrhea
    More Guidelines
  • Patient leaflets

    Diarrhea in adults

    Diarrhea in children

    More Patient leaflets
  • padlock-lockedLog in or subscribe to access all of BMJ Best Practice

Use of this content is subject to our disclaimer