Viral Infections USMLE Step 1 Practice Question
A 22-year-old woman with no significant past medical history presents to the emergency department with a 7-day history of fever, cough productive of blood-tinged sputum, and progressive dyspnea. She reports initial symptoms of myalgias and headache that improved, followed by worsening respiratory symptoms over the past 2 days. Temperature is 38.4°C, heart rate 118 bpm, respiratory rate 26/min, blood pressure 116/74 mmHg, and oxygen saturation 89% on room air. Chest X-ray demonstrates diffuse bilateral interstitial infiltrates with areas of consolidation. Rapid influenza A antigen test is positive. Laboratory studies show WBC 13,800/μL with left shift, and arterial blood gas reveals pH 7.32, PaCO2 48 mmHg, PaO2 64 mmHg on room air. Which of the following complications is most likely to develop in this patient?
Answer choices
- APulmonary embolism due to increased D-dimer from viral infection
- BAcute myocarditis with cardiogenic shock from direct viral invasion
- CSecondary bacterial pneumonia progressing to acute respiratory distress syndromeCorrect answer
- DPneumothorax from barotrauma during mechanical ventilation
- ESeptic shock from primary influenza viremia
- FAcute hypersensitivity pneumonitis from immune complex deposition
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