Virology USMLE Step 1 Practice Question
A 67-year-old man with no significant past medical history presents to the emergency department with acute onset of severe burning pain in the right forehead and upper eyelid, followed 2 days later by grouped vesicles in the V1 distribution of the trigeminal nerve. He reports a history of chickenpox at age 8. On examination, vesicles are noted on the forehead and upper eyelid, and corneal sensation is diminished. He is concerned about potential vision loss. Which of the following best explains why reactivation of varicella-zoster virus in the V1 distribution carries increased risk for ocular complications compared to reactivation in other trigeminal divisions?
Answer choices
- AThe trigeminal ganglion harbors latent VZV, and V1 reactivation provides direct nerve supply to structures of the eye including the corneaCorrect answer
- BReactivation of VZV in V1 triggers hematogenous viremia that preferentially targets ocular endothelial cells due to enhanced vascular permeability in older adults
- CAge-related immunosenescence specifically impairs T-cell responses in the corneal epithelium, allowing unrestricted viral replication
- DThe ophthalmic artery provides rich vascular supply to the V1 nerve, allowing rapid systemic dissemination and secondary seeding of viral particles to the posterior segment
- EReactivation of VZV in the geniculate ganglion causes Ramsay Hunt syndrome, which includes ocular involvement as a mandatory clinical feature
- FVZV has selective neurotropism for the ophthalmic branch due to unique viral glycoprotein variants that are expressed only in V1 sensory neurons
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