Pneumonia USMLE Step 1 Practice Question
A 73-year-old woman with chronic systolic heart failure presents with gradually worsening dyspnea over 3 days. Vital signs show BP 158/92 mmHg, HR 108, RR 22, SpO2 92% on room air. Chest radiograph demonstrates bilateral blunting of costophrenic angles. BNP is elevated at 850 pg/mL. Thoracentesis reveals transudative fluid with protein 2.2 g/dL and LDH 180 IU/L. No fever documented. Which of the following is the most likely diagnosis?
Answer choices
- APulmonary embolism
- BExudative parapneumonic effusion
- CLung abscess
- DTransudative pleural effusion from congestive heart failureCorrect answer
- EEmpyema
- FConstrictive pericarditis with resulting pleural effusion
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