A Case of Diabetic Hemichorea Hemiballismus Exacerbated by Hypoglycemia

We describe an unusual case of diabetic hemichorea hemiballismus (diabetic HCHB) with symptoms resistant to traditional therapy and exacerbated by hypoglycemia.

A 62-year-old woman with a 3-year history of noninsulin dependent type 2 diabetes presented with left-sided, involuntary, "jerking" movements. History included inconsistent metformin use, peripheral vascular disease, hypertension, and hyperlipidemia. Physical exam was documented as chorea of the left upper and lower extremity. Blood glucose was 776 mg/dL (82-115 mg/dL), and head computed tomography scan was read as asymmetric hyperattenuation of the right lentiform nucleus. The chorea dissipated within 48 hours of basal, bolus insulin and maintenance of blood glucose from 140 to 180 mg/dL. Hyperintensities were not documented on magnetic resonance imaging 4 days later. The patient presented twice in the following weeks for increasing frequency of chorea and hypoglycemia of 62 mg/dL and 40 mg/dL. Repeat magnetic resonance imaging was read as right-sided basal ganglia hyperintensities. Short courses of haloperidol, alprazolam, and tizanidine and a 2-week course of olanzapine yielded no improvement in chorea. Two weeks of tetrabenazine did improve the chorea; however, residual weakness and gait dysfunction persisted.

The differential diagnosis for chorea includes hereditary and acquired forms. Diabetic HCHB is a rare, acquired, metabolic form that occurs in older, female, type 2 diabetics with poor glucose control. The patient experienced exacerbations of chorea in the setting of hypoglycemia.

Glycemic control is important in the long-term management of diabetic HCHB, and this case demonstrates hypoglycemia as a potential cause for resistant cases.