Neuromuscular Disorders USMLE Step 1 Practice Question
A 58-year-old man presents with 8 months of progressive weakness in his hands and legs. Vital signs: BP 128/76, HR 82, RR 16, temp 37°C, SpO2 98%. Examination reveals muscle atrophy, visible fasciculations, hyperreflexia, and spasticity. Sensation remains intact throughout. EMG shows acute denervation potentials and motor unit action potentials. He denies recent weight loss. Which of the following is the most likely diagnosis?
Answer choices
- AAmyotrophic lateral sclerosisCorrect answer
- BNormal pressure hydrocephalus
- CGuillain-Barré syndrome
- DPolymyalgia rheumatica
- EMyasthenia gravis
- FCervical spondylotic myelopathy
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