Question 45
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An 8-year-old boy presents to your clinic with a history of nonproductive cough and recurrent opportunistic infections. His mother claims that the symptoms first arose about 2 years ago and previous physicians suspected an immune deficiency disorder. A chest X-ray reveals patchy infiltrates and diffuse clouding. Bronchiolar lavage identifies numerous neutrophils arranged in isolated conglomerates. Nitroblue tetrazolium dye reduction test is negative. Which enzyme is most likely deficient in this child?
Correct Answer: D. NADPH Oxidase
The child classically presents with chronic granulotamous disease, which results from NADPH Oxidase deficiency. Since NADPH Oxidase and related enzymes are critical in the phagocytic responses of neutrophils, the deficient neutrophils are incapable of destroying common bacteria, and opportunistic infections abound. The nitroblue test is specifically performed to determine the presence of NADPH Oxidase.
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Category: ImmunologyAn 8-year-old boy presents to your clinic with a history of nonproductive cough and recurrent opportunistic infections. His mother claims that the symptoms first arose about 2 years ago and previous physicians suspected an immune deficiency disorder. A chest X-ray reveals patchy infiltrates and diffuse clouding. Bronchiolar lavage identifies numerous neutrophils arranged in isolated conglomerates. Nitroblue tetrazolium dye reduction test is negative. Which enzyme is most likely deficient in this child?
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