Bacterial Infections USMLE Step 1 Practice Question
A 36-year-old pet shop employee presents with fever (38.9°C), dry cough, headache, and malaise after cleaning cages of sick parrots two weeks ago. Vital signs show HR 102/min, RR 22/min, SpO2 94% on room air. Chest radiograph demonstrates patchy bilateral infiltrates. Sputum culture remains negative for typical bacteria. He denies recent antibiotic use. Which organism is most likely responsible for this infection?
Answer choices
- AChlamydophila psittaciCorrect answer
- BInfluenza A virus
- CLegionella pneumophila
- DMycoplasma pneumoniae
- ECoxiella burnetii
- FHistoplasma capsulatum
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