Stool microscopy from a child with rectal prolapse shows oval eggs with a mucus plug at one pole. Adult worms recovered from the colon are 4 cm long, barrel-shaped with three lips. Which helminth is responsible, and which drug is the treatment of choice?
- A Ascaris lumbricoides; mebendazole
- B Trichuris trichiura; mebendazole or albendazole ✓
- C Enterobius vermicularis; mebendazole
- D Strongyloides stercoralis; ivermectin
Correct answer: B. Trichuris trichiura; mebendazole or albendazole
Explanation
Trichuris trichiura (whipworm) produces characteristic barrel-shaped (lemon-shaped) eggs with conspicuous polar plugs at both ends. Heavy infections cause Trichuris dysentery syndrome with rectal prolapse. Adult worms are whip-shaped with a narrow anterior and thick posterior. Mebendazole or albendazole is the drug of choice. Ascaris eggs are mammillated and oval without polar plugs. Enterobius eggs are asymmetric and flattened on one side.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
Written and medically reviewed by the StethoPrep medical team.