A 3-year-old child with recurrent infections and hemolytic anemia is found to have reduced neutrophil oxidative burst. Peripheral smear shows Heinz bodies. Which enzyme deficiency most likely explains both findings?

• A Pyruvate kinase
• B Aldolase B
• C Transketolase
• D Glucose-6-phosphate dehydrogenase (G6PD) ✓

Explanation

G6PD is the first enzyme of the hexose monophosphate (HMP) shunt, generating NADPH from NADP+. In erythrocytes, NADPH maintains glutathione in its reduced form, protecting against oxidative hemolysis; Heinz bodies represent precipitated oxidized hemoglobin. In neutrophils, NADPH is the essential electron donor for NADPH oxidase used in the oxidative burst to kill pathogens, explaining recurrent infections in G6PD deficiency.

Reference: Harper's Illustrated Biochemistry, 32nd ed.

High-yield for: NEET PGINI-CETNExTFMGEUSMLEPLABMRCP

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