Last reviewed: 25 Sep 2021
Last updated: 29 May 2020



History and exam

Key diagnostic factors

  • presence of risk factors
  • diarrhoea

Other diagnostic factors

  • generalised abdominal pain
  • right upper quadrant abdominal pain
  • weight loss
  • cough
  • fever
  • altered mental status or limb weakness
  • dyspnoea
  • guarding and rebound tenderness of the abdomen
  • jaundice
  • right lung decreased air entry and percussion note

Risk factors

  • exposure in endemic areas
  • institutionalisation of intellectually disabled people
  • men who have sex with men
  • oral-anal sexual contact
  • HIV infection, past or current syphilis infection
  • male sex

Diagnostic investigations

1st investigations to order

  • stool antigen detection
  • PCR or qPCR of stool or liver abscess pus for E histolytica DNA
  • serum antibody test

Investigations to consider

  • stool microscopy
  • colonoscopy
  • liver ultrasound
  • CXR
  • CT liver/chest/head
  • MRI brain

Treatment algorithm



Koji Watanabe, MD, PhD

Attending physician

AIDS Clinical Center

National Center for Global health and Medicine




KW is an author of a number of references cited in this topic.


Dr Koji Watanabe would like to gratefully acknowledge Dr William A. Petri, a previous contributor to this topic. WAP is a consultant for TechLab, Inc. which manufactures diagnostic tests for amoebiasis and is also the author of a number of references cited in this topic.

Peer reviewers

Ran Nir-Paz, MD

Senior Lecturer in Microbiology and Medicine

Department of Clinical Microbiology and Infectious Diseases

Hadassah-Hebrew University Medical Center




RNP declares that he has no competing interests.

Christopher Huston, MD

Assistant Professor of Medicine

Division of Infectious Diseases

University of Vermont College of Medicine




CH declares that he has no competing interests.

Use of this content is subject to our disclaimer