A 10-year-old boy presents with dry cough, wheezing, low-grade fever, and transient pulmonary infiltrates on chest X-ray. Peripheral eosinophilia is noted. Stool examination later reveals round to oval eggs with a thick mamillated coat. Which organism is responsible?

• A Strongyloides stercoralis
• B Trichinella spiralis
• C Enterobius vermicularis
• D Ascaris lumbricoides ✓

Explanation

Ascaris lumbricoides larval migration through the lungs causes Löffler's syndrome: cough, wheezing, transient pulmonary infiltrates, and eosinophilia. The thick mamillated coat of fertilized Ascaris eggs in stool is pathognomonic. Strongyloises also migrates through lungs but larvae (not eggs) are found in stool; Trichinella does not have an intestinal egg stage; Enterobius does not migrate through lungs.

Reference: Paniker's Textbook of Medical Parasitology, 8th ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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