Neuromuscular Disorders USMLE Step 1 Practice Question
A 32-year-old man presents with jaw stiffness and painful generalized muscle spasms 1 week after a puncture wound from a rusty nail. Vital signs show BP 145/92 mmHg, HR 110/min, RR 22/min, temperature 38.2°C, SpO2 98% on room air. Examination reveals risus sardonicus, opisthotonos, and positive Kernig sign. Serum electrolytes and lumbar puncture are normal. He has not received tetanus prophylaxis in 10 years. Which diagnosis best explains these findings?
Answer choices
- ALambert Eaton myasthenic syndrome
- BMyasthenia gravis
- CTetanusCorrect answer
- DSpinal muscular atrophy
- EBotulism
- FStrychnine poisoning
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