Skip to content
Font Size
A
A
A

Antigen Tests for Giardiasis

For a giardia antigen test, a stool sample or fluid from the upper part of the intestines (duodenal fluid) is tested in the lab for the presence of antigens from Giardia lamblia. This test is often done at the same time as a stool analysis.

Why It Is Done

An antigen test may be done if a person's medical history and symptoms suggest giardiasis. This test may be done to check if the person has been cured after treatment. An antigen test also may be used to screen people who are at high risk for having giardiasis.

Results

A test that detects Giardia antigens (positive result) indicates that the person has giardiasis. If the infected person does not have symptoms of infection, he or she may be a carrier or have an chronic infection.

These tests are specific for Giardia lamblia and do not test for other intestinal infections that cause similar symptoms. A person may get infected with other organisms that cause the same symptoms if he or she travels to countries where these organisms are found.

If the test does not detect antigens (negative result), it may need to be repeated to rule out giardiasis.

What To Think About

These tests may be done on a stool sample before testing the fluid from the small intestines (duodenal contents). Antigen tests are very likely to detect Giardia lamblia if it is present and may be used instead of a stool analysis when giardiasis is likely. Stool samples may be tested to detect antigens (proteins that come from Giardia lamblia) or to detect the actual parasites.

Complete the medical test information form (PDF)(What is a PDF document?) to help you prepare for this test.

Related Information

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerW. David Colby IV, MSc, MD, FRCPC - Infectious Disease

Current as ofNovember 14, 2014

WebMD Medical Reference from Healthwise

Last Updated: November 14, 2014
This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.

Hot Topics

WebMD Video: Now Playing

Click here to wach video: Dirty Truth About Hand Washing

Which sex is the worst about washing up? Why is it so important? We’ve got the dirty truth on how and when to wash your hands.

Click here to watch video: Dirty Truth About Hand Washing

Popular Slideshows & Tools on WebMD

disciplining a boy
Types, symptoms, causes.
psoriasis
Does your kid have symptoms?
fruit drinks
Eat these to think better.
No gym workout
Moves to help control blood sugar.
acupuncture needle on shoulder
10 tips to look and feel good.
Close up of eye
12 reasons you're distracted.
Epinephrine Injection using Auto-Injector Syringe
Life-threatening triggers.
woman biting a big ice cube
Habits that wreck your teeth.
embarrassed woman
Do you feel guilty after eating?
pacemaker next to xray
Treatment options.
caregiver with parent
10 tips for daily life.
birth control pills
Which kind is right for you?

Pollen counts, treatment tips, and more.

It's nothing to sneeze at.

Loading ...

Sending your email...

This feature is temporarily unavailable. Please try again later.

Thanks!

Now check your email account on your mobile phone to download your new app.

Women's Health Newsletter

Find out what women really need.