Pneumonia USMLE Step 1 Practice Question
A 34-year-old pet store employee presents with fever, severe headache, dry cough, and myalgias for 5 days. Vital signs show temperature 39.2°C, heart rate 102/min, respiratory rate 22/min, blood pressure 118/76 mmHg, and SpO2 98% on room air. Chest radiograph reveals patchy interstitial infiltrates. Laboratory studies show normal white blood cell count. She denies dyspnea and recently cared for sick parrots. Which organism most likely explains her clinical presentation?
Answer choices
- AChlamydophila psittaciCorrect answer
- BStreptococcus pneumoniae
- CMycoplasma pneumoniae
- DHistoplasma capsulatum
- ELegionella pneumophila
- FCoxiella burnetii
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