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Last reviewed: 22 Apr 2025
Last updated: 04 Jul 2023

Summary

Definition

History and exam

Key diagnostic factors

  • presence of risk factors

Other diagnostic factors

  • asymptomatic
  • co-infection with other parasites
  • developmental delay
  • malnutrition
  • fever
  • cough
  • wheezing
  • dyspnoea
  • haemoptysis
  • hypoxia
  • tachypnoea
  • rhonchi, rales
  • retractions
  • urticarial skin lesions
  • abdominal pain
  • anorexia
  • dyspepsia
  • nausea
  • vomiting
  • diarrhoea
  • constipation
  • abdominal distension
  • reduced or absent bowel sounds
  • hypotension
  • RUQ tenderness
  • hepatomegaly
  • jaundice
  • signs/symptoms of iron deficiency anaemia or kwashiorkor

Risk factors

  • history of travel to or residence in endemic areas
  • children <14 years
  • poverty
  • poor sanitation
  • poor hygiene
  • warm climate
  • contact with pigs

Diagnostic investigations

1st investigations to order

  • stool microscopy
  • chest x-ray
  • abdominal x-ray

Investigations to consider

  • sputum/gastric aspirate microscopy
  • FBC
  • contrast study
  • barium follow-through
  • abdominal ultrasound
  • abdominal CT
  • endoscopic retrograde cholangiopancreatography (ERCP)

Emerging tests

  • antibodies to Ascaris lumbricoides
  • serum IgE
  • interleukin (IL)-4, IL-5, and IL-13
  • urine-based gas liquid chromatography

Treatment algorithm

Contributors

Authors

Michael Cappello, MD

Professor of Pediatrics, Microbial Pathogenesis, and Public Health

Yale School of Medicine

New Haven

CT

Disclosures

MC declares that he has no competing interests.

Acknowledgements

Dr Michael Cappello would like to gratefully acknowledge Dr Samantha H. Johnston and Dr Claire Panosian, previous contributors to this topic.

Disclosures

SHJ owns a share in a company (Merck & Co., Inc.) that produces ivermectin, an alternative therapy for ascariasis. CP declares that she has no competing interests.

Peer reviewers

Yann Meunier, MD

Director

Stanford Health Promotion Network

Stanford School of Medicine

Palo Alto

CA

Disclosures

YM declares that he has no competing interests.

Mohammad Bagher Rokni, PhD

Associate Professor

Department of Medical Parasitology and Mycology

School of Public Health

Tehran University of Medical Sciences

Iran

Disclosures

MBR declares that he has no competing interests.

References

Our in-house evidence and editorial teams collaborate with international expert contributors and peer reviewers to ensure that we provide access to the most clinically relevant information possible.

Key articles

World Health Organization. Soil-transmitted helminthiasis. Jan 2023 [internet publication].Full text

Centers for Disease Control and Prevention. Parasites - ascariasis: resources for health professionals. May 2020 [internet publication].Full text

World Health Organization. Preventive chemotherapy to control soil-transmitted helminth infections in at-risk population groups. September 2017 [internet publication].Full text

Khuroo MS. Ascariasis. Gastroenterol Clin North Am. 1996;25:553-577. Abstract

Reference articles

A full list of sources referenced in this topic is available here.

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