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Pinworm Test


This test is used to detect the presence of pinworms.

Pinworms are small, thin worms that commonly infect young children, although anyone can be infected. The adult pinworms live in the intestine and colon. At night, the female adult worms deposit their eggs outside the rectum or anal area.

Alternative Names

Oxyuriasis test; Enterobiasis test; Tape test

How the test is performed

One way to diagnose pinworms is to use a flashlight to inspect the anal area. The worms are tiny, white, and threadlike. If none are seen, check for two or three additional nights.

The best way to diagnose this infection is to do a tape test. The best time to collect a sample is in the morning before bathing, because the eggs are laid at night. The sticky side of a 1 inch strip of cellophane tape is pressed firmly over the anal area for a few seconds. The eggs stick to the tape. The tape is then transferred to a glass slide, sticky side down. The slide should then be examined by your health care provider to look for eggs.

To improve the chances of picking up the eggs, this test may need to be done on three separate days.

How to prepare for the test

No special preparation is necessary.

How the test will feel

This test is usually well tolerated. The skin may have minor irritation.

Why the test is performed

This test is performed to check for pinworms, which are a potential cause of itching in the anal area.

What abnormal results mean

If any adult pinworms or eggs are found, the person has a pinworm infection.

What the risks are

There are no risks.

Special considerations

Consult your health care provider for treatment. Usually the whole family is treated, because the pinworms are easily passed back and forth between family members.

Review Date: 8/1/2008

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Information developed by A.D.A.M., Inc. regarding tests and test results may not directly correspond with information provided by UCSF Medical Center. Please discuss with your doctor any questions or concerns you may have.