Viral Infections USMLE Step 1 Practice Question
A 7-year-old unimmunized boy presents with fever (39.2°C), pharyngitis, and progressive asymmetric right leg weakness over 3 days. Heart rate is 102 bpm, respiratory rate 18/min, SpO2 98% on room air. Sensation remains intact; deep tendon reflexes are diminished in the affected limb. CSF analysis reveals lymphocytic pleocytosis (145 cells/μL, 85% lymphocytes) with normal glucose. Cranial nerves are unaffected. Which organism is most likely responsible?
Answer choices
- APoliovirusCorrect answer
- BHerpes simplex virus 1
- CVaricella zoster virus
- DWest Nile virus
- ERabies virus
- FGuillain-Barre syndrome causing symmetric ascending weakness not asymmetric
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