Organ System Pathology USMLE Step 1 Practice Question
A 66-year-old man with hypertension presents with abrupt fever (39.2°C), pleuritic chest pain, productive cough with rust-colored sputum, and dyspnea. Vital signs show BP 148/92 mmHg, HR 102/min, RR 22/min, SpO2 92% on room air. Examination reveals bronchial breath sounds and egophony over the right lower lobe. Chest radiograph demonstrates lobar consolidation of the right lower lobe. WBC is 15,200/μL. Which organism is most likely responsible?
Answer choices
- AMycoplasma pneumoniae
- BLegionella pneumophila
- CChlamydophila psittaci
- DStreptococcus pneumoniaeCorrect answer
- EKlebsiella pneumoniae
- FHaemophilus influenzae
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