[Effectiveness of levodopa treatment for diabetic chorea with reduced striatal accumulation in dopamine transporter SPECT: a case report].

We report the case of a 77-year-old woman with diabetic chorea, which presented as hemiballism of the right limbs. Initial blood examination revealed that sugar and hemoglobin A1c levels were 732 mg/dl and 12.2%, respectively. Thus, a diagnosis of hyperglycemic hyperosmolar syndrome was made at a previous hospital. Ballism of the right limbs developed after 10 days and progressively worsened. After a month, the patient was admitted to our hospital. Brain MRI (axial T1-weighted imaging) revealed a high-signal-intensity area in the left striatum. Dopamine transporter SPECT demonstrated reduced 123I-ioflupane binding in the bilateral striatum with left side predominance. Although haloperidol and risperidone were ineffective for her involuntary movement, chlorpromazine had a little effect. Levodopa and gabapentin combination treatments were effective in decreasing the symptoms. It was considered that dopamine antagonist was the medical treatment for diabetic chorea and that levodopa could worsen neurological symptoms such as chorea-ballism. However, in our case, levodopa treatment was effective.