COPD USMLE Step 1 Practice Question
A 5-month-old boy presents to the emergency department in winter with cough, wheezing, poor feeding, and increased work of breathing. He attends daycare. Vital signs show temperature 38.2°C, heart rate 148/min, respiratory rate 52/min, blood pressure 95/60 mmHg, and oxygen saturation 89% on room air. Examination reveals diffuse crackles and wheezes. Chest X-ray shows hyperinflation with peribronchial thickening. He denies fever for past 24 hours. Which pathogen is most likely responsible?
Answer choices
- ABordetella pertussis
- BAdenovirus type 40
- CRespiratory syncytial virusCorrect answer
- DParainfluenza virus
- EInfluenza B virus
- FHuman metapneumovirus
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