Giardia duodenalis antigen in stool (qualitative immunoassay)
This test checks for the presence of Giardia duodenalis, a microscopic parasite that can cause intestinal infections, often leading to symptoms like diarrhea, stomach cramps, or bloating. It’s used to diagnose giardiasis, a common parasitic infection.
["A positive result may indicate an infection requiring treatment, while a negative result suggests no active infection at the time of testing."]
Key facts at a glance
- LOINC
- 10724-3
- Short code
- T gondii IgE Ser IA-aCnc
- Synonyms
- T gondii IgE Ser IA-aCnc
- Category
- chemistry
- Sample
- serum
- Container
- Red-top tube (SST)
- Units
- N/A
- Fasting
- false
- Population
- adult
- Sex
- all
- Age range
- 18–65 years
- Method
- ia
- Specimen volume
- 5 mL
- Stability
- Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
- Hemolysis max
- 500
- Lipemia max
- 1000
- Icterus max
- 500
- TAT
- 4–24 hours
- Order
- routine
Why This Test Matters
Giardia duodenalis is a single-celled parasite that can infect the small intestine, causing symptoms like persistent diarrhea, gas, nausea, or weight loss. It’s often spread through contaminated water or food. This test helps confirm if you have an active infection, guiding treatment decisions.
How the Test Works
The test uses an immunoassay (a lab method that detects specific proteins from the parasite) to identify Giardia antigens in your stool sample. If the parasite is present, the test will detect its unique proteins, confirming infection.
Preparation for the Test
No special preparation is needed, but you may be asked to collect a stool sample at home or in a lab. Follow your healthcare provider’s instructions to ensure accurate results. Avoid using certain medications or supplements that could interfere with the test.
What the Results Mean
A **positive result** means the test detected Giardia antigens in your stool, suggesting an active infection. This usually requires medical treatment with antiparasitic medications. A **negative result** means no active infection was found at the time of testing, but reinfection is possible.
Clinical interpretation
How abnormal results are interpreted and what conditions they suggest.
Giardiasis can cause significant discomfort and may lead to dehydration or malnutrition if untreated. It’s especially concerning in travelers, those with weakened immune systems, or individuals in areas with poor sanitation. Early diagnosis and treatment help prevent complications and reduce transmission to others.
Short name
Giardia stool test (qualitative)
Frequently asked questions
What causes Giardiasis?
How long does it take to get results?
Can I treat Giardiasis at home?
Sources
- 1
- 2Lab Tests OnlineSource
- 3
Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.
This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.
This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.
If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.
Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy