Pneumonia USMLE Step 1 Practice Question
A 72-year-old man with COPD presents with fever, cough productive of purulent sputum, and dyspnea for 3 days. Chest X-ray shows a consolidation in the right lower lobe. Sputum culture grows gram-negative rods that are oxidase-positive and produce a green pigment. Which of the following is the most likely organism?
Answer choices
- APseudomonas aeruginosaCorrect answer
- BKlebsiella pneumoniae
- CMoraxella catarrhalis
- DHaemophilus influenzae
- ELegionella pneumophila
- FBurkholderia cepacia
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