Immunology USMLE Step 1 Practice Question
A 3-year-old female presents with recurrent subcutaneous abscesses and furuncles. Vital signs show temperature 37.8°C, HR 98/min, BP 95/62 mmHg, RR 22/min, and SpO2 98% on room air. She has a history of pneumonia caused by Serratia marcescens. Laboratory studies reveal normal immunoglobulin levels and normal neutrophil count (7,200/μL). A chest radiograph shows no current infiltrates. Which of the following enzymes is most likely deficient in her neutrophils?
Answer choices
- ANADPH oxidaseCorrect answer
- BAldolase B
- CGlucose-6-phosphate dehydrogenase
- DGlucokinase
- EGalactokinase
- FMyeloperoxidase
See the full explanation
Get the correct-answer rationale, why each distractor is wrong, the underlying mechanism, and high-yield associations — plus adaptive practice that targets your weak areas — with a free MedBoardPRO account.