Neuromuscular Disorders USMLE Step 1 Practice Question
A 12-year-old unvaccinated boy presents with sore throat and a gray pharyngeal membrane. Three weeks after symptom onset, he develops palatal weakness and distal paresthesias. Vital signs show BP 118/76 mmHg, HR 92/min, RR 18/min, temperature 37.2°C, and SpO2 98% on room air. Nerve conduction studies demonstrate prolonged distal latencies with preserved conduction velocities. Gag reflex remains intact. Which of the following best explains this neurologic complication?
Answer choices
- AAutoantibodies against acetylcholine receptors
- BImmune complex vasculitis of medium sized arteries
- CDirect viral destruction of anterior horn cells
- DGlutamate mediated excitotoxicity
- EToxin mediated demyelinating peripheral neuropathyCorrect answer
- FImmune mediated segmental demyelination of motor nerves
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