Which symptom is most characteristic of pinworm infection?

• A. Diarrhea
• B. Jaundice
• C. Anal itching worse at night
• D. Severe coughing

Answer: (C)

Pinworm infection is most clearly identified by intense anal itching caused by the female worms laying eggs around the anus, which typically happens at night. This nocturnal activity leads to scratching, sleep disturbance, and sometimes secondary skin irritation or infection around the area. The key point is that the itching is localized to the perianal region and follows a nightly pattern, which is distinctive for pinworms.

Diarrhea, jaundice, and severe coughing aren’t characteristic features of pinworm infection. Diarrhea isn’t the hallmark manifestation, jaundice points to liver or biliary issues, and coughing suggests a respiratory problem rather than a perianal parasitic infection.