A patient with falciparum malaria develops severe haemolysis, haemoglobinuria, and acute kidney injury within hours of receiving primaquine. Which enzyme deficiency is responsible for this complication?
- A Pyruvate kinase deficiency
- B Spectrin deficiency (hereditary spherocytosis)
- C Glucose-6-phosphate dehydrogenase (G6PD) deficiency ✓
- D Glutathione synthetase deficiency
Explanation
G6PD deficiency is an X-linked condition that renders red cells vulnerable to oxidative stress because the pentose phosphate pathway cannot regenerate NADPH to maintain glutathione in reduced form. Primaquine and dapsone are strong oxidizing agents that cause haemolysis in G6PD-deficient individuals — the classic presentation is acute intravascular haemolysis with dark ('coca-cola') urine (haemoglobinuria) and AKI. This is especially relevant in the Indian subcontract where G6PD deficiency is common and primaquine is used for P. vivax radical cure and P. falciparum gametocyte clearance. G6PD testing is recommended before primaquine administration.
Reference: Ananthanarayan & Paniker's Textbook of Microbiology, 11th ed.
High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP
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