When I suspect pinworms in children, I do a test tube proctoscopy. I apply some clear lubrication jelly on the closed end of a 5 mL test tube and insert this gently into the child’s rectum. Then, I use my pocket pen light to look for the pinworms. I use the same method to look for other rectal pathology in children.
The Centers for Disease Control and Prevention also recommends these diagnostic techniques:
- Look for the worms in the perianal reqion 2 to 3 hours after the infected person is asleep.
- Touch the perianal skin with transparent tape to collect possible pinworm eggs around the anus first thing in the morning. Eggs on the tape will be visible under a microscope. Conduct the tape method on 3 consecutive mornings right after the infected person wakes up and before he/she does any washing.
- Since anal itching is a common symptom of pinworm, look at samples from under the fingernails with a microscope. An infected person who has scratched may have picked up some pinworm eggs under the nails.