[Hyperglycemia and symmetrical proximal neuropathy in diabetes]

A 60-year-old woman, diagnosed as having a diabetic symmetrical proximal motor neuropathy, is presented. In March 1995, she was referred to us because of untreated diabetes mellitus since 1990. Insulin treatment during one month decreased her postprandial plasma glucose level from more than 400mg/dl to about 200mg/dl. Soon after the treatment, she noticed lower proximal limb weakness bilaterally. In several months, her weakness progressed as the fasting plasma glucose level was increased. Her muscle power gradually recovered when the plasma glucose level was normalized. We therefore suggest that metabolic changes related to hyperglycemia, rather than ischemic vascular changes, play an important role in the pathogenesis of a diabetic symmetrical proximal motor neuropathy.