Which tapeworm is associated with megaloblastic anaemia due to competition for vitamin B12 at the ileal level?
- A Taenia solium
- B Hymenolepis nana
- C Diphyllobothrium latum ✓
- D Echinococcus granulosus
Correct answer: C. Diphyllobothrium latum
Explanation
Diphyllobothrium latum, the broad fish tapeworm, is the longest human tapeworm and absorbs up to 80 percent of dietary vitamin B12 through its broad proglottids, causing vitamin B12 deficiency with megaloblastic anaemia and sometimes subacute combined degeneration. Infection follows eating raw fish containing plerocercoid larvae, and its eggs are operculated, unlike those of any other human tapeworm. The other listed cestodes do not impair B12 absorption.
Reference: Paniker's Textbook of Medical Parasitology, 8th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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