Pneumonia USMLE Step 1 Practice Question
A 64-year-old man has been mechanically ventilated for 6 days following major trauma. He now presents with fever (38.9°C), tachycardia (102 bpm), tachypnea (24 breaths/min), and increased oxygen requirements (FiO₂ increased from 0.40 to 0.60). Laboratory studies show leukocytosis (WBC 14,500/μL). Chest X-ray demonstrates a new right lower lobe infiltrate. He denies hemoptysis. Which organism requires empiric coverage in this clinical scenario?
Answer choices
- APseudomonas aeruginosaCorrect answer
- BMycoplasma pneumoniae
- CChlamydophila psittaci
- DStreptococcus pneumoniae
- EHistoplasma capsulatum
- FLegionella pneumophila
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