Immunology USMLE Step 1 Practice Question
A 27-year-old man presents with fever (39.2°C), cough, and dyspnea. Vital signs show BP 118/76, HR 102, RR 22, SpO2 88% on room air. Chest X-ray reveals bilateral infiltrates. Blood cultures grow Histoplasma capsulatum. Laboratory studies show normal neutrophil count and function, but impaired macrophage microbicidal activity against the organism. He denies antiretroviral use. Which cytokine is most important for activating macrophages to kill this intracellular pathogen?
Answer choices
- AIL 5
- BIL 4
- CIFN gammaCorrect answer
- DTGF beta
- EIL 10
- FIL-2
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