Clinical Reasoning: A 65-year-old man with asymmetric weakness and paresthesias

摘要

A 65-year-old man with well-controlled diabetes presented with 3 months of progressive leftside predominant weakness accompanied by painless paresthesias of his bilateral upper and lower extremities. The onset was with tingling and numbness in his toes, which later involved his fingers. Over a few weeks, he developed progressive weakness of his left lower extremity followed by the right lower extremity and later involvement of both upper extremities. By the time of presentation, the patient was unable to sit or walk without support and reported weight loss of 35 pounds over 3 months. The patient denied any toxic substance exposure, insect bites, recent illness or travel, family history of neuropathy, or any episodes suggestive of recurrent compressive neuropathies. His examination showed moderately severe asymmetric weakness (Medical Research Council scale: 3-4/5 on the left, 4-5/5 on the right) of the upper and lower extremities (distal more than proximal). There was asymmetric muscle atrophy; however, deep tendon reflexes were 2+ in the right biceps and triceps, 1+ in the left biceps, triceps, and bilateral ankles, and absent in the knees bilaterally. The sensory examination revealed left-sided predominant loss of pinprick in a patchy distribution in legs and loss of vibration sense in the toes. The remaining neurologic examination was unremarkable.