Involuntary choreiform movements in a diabetic patient

A 62-year-old woman was admitted to our hospital because she had been having involuntary movement of her right arm and leg for the previous month. In her medical history, she had developed type 2 diabetes approximately 10 years ago, which was treated with metformin and glimepiride. However, her blood glucose had been poorly controlled. A physical examination showed involuntary, unilateral, choreiform movements affecting only her right side (video). Further neurological examination showed her cranial nerves to be intact, ocular examination was normal, and there were no abnormal pyramidal signs—specifically, muscle strength was normal, and tone and reflexes were normal.