String test

Alternative names:

duodenal parasites test

How the test is performed:

You swallow a string with a weighted gelatin capsule on the end and then it is pulled back out after 4 hours. Any bile, blood, or mucus attached to the string is examined under the microscope for cell types and segments of parasites or eggs.

How to prepare for the test:

Food and fluid may be restricted for 12 hours before the test.

Infants and children:
The physical and psychological preparation you can provide for this or any test or procedure depends on your child's age, interests, previous experience, and level of trust. For specific information regarding how you can prepare your child, see the following topics as they correspond to your child's age:

• infant test or procedure preparation (birth to 1 year)
• toddler test or procedure preparation (1 to 3 years)
• preschooler test or procedure preparation (3 to 6 years)
• schoolage test or procedure preparation (6 to 12 years)
• adolescent test or procedure preparation (12 to 18 years)

How the test will feel:

It may be difficult to swallow the string. Some people may vomit when the string is pulled up.

Why the test is performed:

The test is performed when there is a suspicion of parasitic infestation, and parasites are not detected by stool examination.