Hemichorea in a patient with high glucose variability: a case report

Hemichorea-hemiballismus related to diabetes is usually associated with non-ketotic hyperglycemia in older adults. We report a rare case of diabetic striatopathy in a 92-year-old man who presented with hemichorea despite normoglycemia (95 mg/dl) on admission. He had stopped diabetes medication 7 months earlier after hypoglycemia. Laboratory studies showed elevated ketone bodies, hemoglobin A1c of 15.7%, and glycated albumin of 36.4%, indicating chronic poor glycemic control and marked glucose variability. Brain magnetic resonance imaging revealed T1 hyperintensity in the left putamen, and fluorodeoxyglucose positron emission tomography-computed tomography demonstrated corresponding hypometabolism. No alternative neurological or infectious causes were identified. Symptoms improved with haloperidol, clonazepam, and resumption of diabetes therapy. This case suggests that hemichorea can occur in the setting of significant glycemic variability even without overt hyperglycemia, potentially through oxidative stress and reactive astrogliosis. However, short-term glucose data before symptom onset were unavailable, limiting assessment of recent glycemic fluctuations.