Viral Infections USMLE Step 1 Practice Question
A 22-year-old male college student presents to urgent care with a 3-day history of severe sore throat, fever, and malaise. Temperature is 39.5°C, heart rate 102 bpm, respiratory rate 18/min, and blood pressure 118/76 mmHg. On examination, he has bilateral tonsillar exudates with a white-gray pseudomembrane, marked anterior cervical lymphadenopathy, and mild hepatosplenomegaly on palpation. He denies cough, rhinorrhea, and diarrhea. A rapid streptococcal antigen test is negative. Complete blood count shows WBC 12,000/μL with 65% atypical lymphocytes. Monospot heterophile antibody test is positive. Which of the following is the most likely causative organism?
Answer choices
- AParainfluenza virus type 1
- BEpstein-Barr virusCorrect answer
- CCytomegalovirus
- DCoxsackievirus A
- EAdenovirus type 3
- FStreptococcus pyogenes
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