A 5-year-old child presents with perianal itching, especially at night. Sellotape swab applied perianally in the morning shows ova that are asymmetric, flattened on one side, and measure approximately 55 × 25 µm. The most appropriate treatment is:

• A Albendazole 400 mg single dose, repeat after 2 weeks ✓
• B Mebendazole 100 mg twice daily for 3 days
• C Pyrantel pamoate 11 mg/kg single dose
• D Piperazine citrate for 7 days

Explanation

Enterobius vermicularis (pinworm/threadworm) is diagnosed by the Sellotape (scotch tape) perianal swab, which recovers the characteristic plano-convex (D-shaped) eggs. Albendazole 400 mg as a single dose repeated at 2 weeks (to eliminate newly hatched worms) is the current WHO-recommended treatment; the entire household should be treated simultaneously. Mebendazole 100 mg single dose is equally effective. Pyrantel pamoate is also effective as a single dose but less commonly used now.

Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

Written and medically reviewed by the StethoPrep medical team.