Inflammation and Immune Pathology USMLE Step 1 Practice Question
A 4-year-old boy presents with recurrent skin abscesses and pneumonias caused by catalase-positive organisms. Vital signs show HR 102/min, RR 24/min, temperature 38.2°C, BP 95/60, SpO2 98% on room air. Nitroblue tetrazolium test demonstrates absent color change. Chest X-ray reveals right lower lobe infiltrate. He denies recent antibiotic use. Which of the following enzyme deficiencies most likely explains his disease?
Answer choices
- ADefective NADPH oxidaseCorrect answer
- BDefective beta 2 integrin
- CDefective myeloperoxidase
- DDefective C3 convertase
- EDefective perforin
- FLeukocyte adhesion deficiency from CD18 integrin deficiency
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