Neuromuscular Disorders USMLE Step 1 Practice Question
A 26-year-old man presents with difficulty releasing his grip after handshaking. He reports daytime sleepiness and progressive frontal balding. Vital signs show BP 118/76, HR 82, RR 16, temperature 37°C, and SpO2 98% on room air. Physical examination reveals early cataracts and testicular atrophy. Serum creatine kinase is mildly elevated at 320 IU/L. Cognitive assessment is intact. He denies recent medication use. Which genetic disorder is most likely responsible for these findings?
Answer choices
- ALambert Eaton myasthenic syndrome
- BDuchenne muscular dystrophy
- CBotulism
- DMyotonic dystrophy type 1Correct answer
- EAmyotrophic lateral sclerosis
- FMyasthenia gravis
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