Skip to content
My WebMD Sign In, Sign Up

Information and Resources

Font Size

String Test for Giardiasis

For this test, you swallow a gelatin capsule attached to a long string. The end of the string remains outside the mouth and is taped to your cheek. The capsule dissolves in the stomach and the string passes into the upper part of the small intestine (duodenum).

The string is left in place for 4 to 6 hours or overnight. Then it is withdrawn and the end is examined under the microscope for parasites that are attached to it.

This test is also called the Enterotest.

Why It Is Done

The string test may be done if other methods (especially examination of stool samples and antigen tests) have failed to detect giardiasis.

This test is rarely done. If a small sample of the small intestine is needed to confirm the diagnosis, endoscopy is usually done.

Results

Findings of the string test may include the following.

Normal

No Giardia parasites are seen when the string is examined.

Abnormal

Giardia parasites can be seen when the string is examined under a microscope.

What To Think About

This test requires you to commit most of a day to the testing procedure. If the string is removed too soon, it may not have had time to reach the small intestine, and the results may be inaccurate. But the test is relatively inexpensive and accurate when done properly.

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

ByHealthwise Staff
Primary Medical ReviewerE. Gregory Thompson, MD - Internal Medicine
Specialist Medical ReviewerW. David Colby IV, MSc, MD, FRCPC - Infectious Disease
Last RevisedSeptember 9, 2011

WebMD Medical Reference from Healthwise

Last Updated: September 09, 2011
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

hands on abdomen
Can you catch one?
Woman sitting in front of UV lights
Is yours working?
woman using breath spray
What's causing yours?
womans hand on abdomen
Are you ready for baby?
MS Overview
Recognizing symptoms.
bowl of yogurt with heart shape
Eat for a healthy heart.
woman doing pushups
To help you get fit.
Colored x-ray of tooth decay
Know what to look for.
Woman sitting with child
Do you know the symptoms?
mosquito
Stings, bites, burns, and more.
Allentown, PA
Are you living in one?
Thyroid exam
See how much you know.

Women's Health Newsletter

Find out what women really need.