ZyraDoc #48 - September 18, 2026

A 6-year-old child is brought to the pediatric clinic by his parent due to intense perianal itching (pruritus ani), which is noticeably worse at night and has caused frequent nocturnal awakenings over the past two weeks.

Upon physical examination, the perianal skin exhibits mild erythema and excoriations from scratching, and the parent reports spotting small, white, thread-like worms near the child's anus late at night.

A transparent adhesive tape test (Scotch tape test) performed early in the morning before bathing reveals characteristic asymmetric, oval eggs with a flattened side under light microscopy.

Case Summary

Clinical Focus:

The diagnosis is Enterobiasis (Pinworm Infection).

Aetiology/Cause:

Infection by the nematode parasite Enterobius vermicularis.
Ingestion of microscopic infectious eggs transferred via contaminated fingers, clothing, bedding, or household surfaces (fecal-oral route and autoinfection).
Nocturnal migration of gravid female worms to the perianal region to deposit thousands of eggs, causing localized intense irritation.

Clinical Features:

Intense perianal and perineal pruritus (itching), particularly severe at night during female worm oviposition.
Restless sleep, nocturnal awakenings, irritability, and behavioral disturbances in young children.
Perianal erythema, excoriations, and secondary bacterial skin infections (e.g., impetigo) secondary to repeated scratching.
Occasional ectopic migration into the female genital tract causing vulvovaginitis or pelvic inflammation.

Diagnosis and Investigations:

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