Viral Infections USMLE Step 1 Practice Question
A 45-year-old man with a history of hepatitis C-related cirrhosis presents to the emergency department with acute dyspnea and hemoptysis that began 6 hours ago. He reports no fever, cough, or recent sick contacts. Vital signs: BP 92/58 mmHg, HR 118 bpm, RR 28/min, SpO2 78% on room air, temperature 37.2°C. Physical examination reveals crackles in bilateral lung bases and splenomegaly. Laboratory studies show INR 3.2, platelet count 45,000/μL, and hemoglobin 9.2 g/dL. Chest X-ray demonstrates bilateral interstitial infiltrates with a ground-glass appearance. Blood cultures are negative. Which of the following viral infections is most likely responsible for this patient's acute pulmonary hemorrhage and respiratory compromise?
Answer choices
- ARespiratory syncytial virus with secondary bacterial superinfection
- BInfluenza A virus with acute respiratory distress syndrome
- CCytomegalovirus pneumonitis with alveolar hemorrhageCorrect answer
- DHepatitis A virus with acute liver failure
- EMeasles virus with giant cell pneumonia
- FRotavirus with aspiration pneumonia
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