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Giardiasis

Last reviewed: 10 Nov 2024
Last updated: 21 Feb 2024

Summary

Definition

History and exam

Key diagnostic factors

  • diarrhea
  • frequent belching
Full details

Other diagnostic factors

  • abdominal bloating and discomfort
  • malaise
  • weight loss
  • nausea and vomiting
Full details

Risk factors

  • contaminated water/food
  • domestic animals living in or around the house
  • hypogammaglobulinemia
  • young age
  • male sex
  • day-care center attendance
  • oral-anal sexual contact
  • recent antibiotic use
Full details

Diagnostic tests

1st tests to order

  • direct fluorescence antibody (DFA) test or enzyme-linked immunosorbent assay
  • nucleic acid amplification test, polymerase chain reaction of stool sample
  • stool microscopy
  • CBC
Full details

Tests to consider

  • Lateral flow immunoassay (e.g., ImmunoCard STAT!)
  • duodenal aspirates and biopsies
  • string test (EnteroTest)
Full details

Treatment algorithm

ACUTE

nonpregnant adult or child

pregnant; first trimester

pregnant; second or third trimester

ONGOING

treatment failure or resistance

Contributors

Authors

Luther A. Bartelt, MD

Assistant Professor of Medicine

University of North Carolina School of Medicine

Division of Infectious Diseases

Chapel Hill

NC

Disclosures

LAB is an editorial board member for PLOS Neglected Tropical Diseases and an author for Elsevier and UpToDate. LAB has received funding from the National Institutes of Health. LAB is the author of two articles cited in this topic.

Acknowledgements

Dr Luther Bartelt would like to gratefully acknowledge Dr Fida Khan and Dr Musaddiq Waheed, previous contributors to this topic.

Disclosures

FK and MW declared that they had no competing interests.

Peer reviewers

Zana Nikolla, MD

Faculty of Medicine

University of Tirana

Tirana

Albania

Disclosures

ZN declares that she has no competing interests.

Rodney Adam, MD

Professor of Medicine and Immunobiology

University of Arizona

Tucson

AZ

Disclosures

RA declares that he has no competing interests.

  • Giardiasis images
  • Differentials

    • Rotavirus or other viral gastroenteritis
    • Functional diarrhea
    • Celiac disease
    More Differentials
  • Guidelines

    • CDC Yellow Book: health information for international travel - giardiasis
    • Functional bowel disorders with diarrhoea
    More Guidelines
  • Patient information

    Diarrhea in adults

    More Patient information
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