Summary
Definition
History and exam
Key diagnostic factors
- diarrhea
- frequent belching
Other diagnostic factors
- abdominal bloating and discomfort
- malaise
- weight loss
- nausea and vomiting
Risk factors
- contaminated water/food
- domestic animals living in or around the house
- hypogammaglobulinemia
- young age
- male sex
- day-care center attendance
- men having sex with men
- recent antibiotic use
Diagnostic investigations
1st investigations 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
Investigations to consider
- Lateral flow immunoassay (e.g., ImmunoCard STAT!)
- string test (EnteroTest)
- duodenal aspirates and biopsies
Treatment algorithm
nonpregnant adult or child
pregnant; first trimester
pregnant; second or third trimester
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 has received funding support from the National Institutes of Health to support giardiasis research and royalties from text authorships (Wolters Kluwer) for chapters about Giardia. 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.
Differentials
- Rotavirus gastroenteritis
- Functional diarrhea
- Celiac disease
More DifferentialsGuidelines
- Adverse events associated with EGD and EGD-related techniques
- CDC yellow book: chapter 4 - travel-related infectious diseases: giardiasis
More GuidelinesPatient leaflets
Diarrhea in adults
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