This man with a positive family history of this disease presents with leg pain, exacerbated by deep palpation of the muscles. He also complains of colicky abdominal pain, constipation, diarrhea, and dysphagia. Recently, his cardiologist told him he had atrial flutter, his primary care doctor noted primary hypogonadism and testicular atrophy, and his ophthalmologist found cataracts. Review of systems picks up excessive daytime sleepiness. When he first comes in to shake your hand, you notice he has trouble letting go; when he leaves, he also has difficulty letting go of the doorknob. You note weakness in the facial muscles, intrinsic hand muscles, and bilateral foot drop.
Challenge: What's the diagnosis?
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