To describe a case of hyperglycemic non-ketotic hemichoreaballism with classic imaging findings.

Hyperglycemic non-ketotic hemichoreaballism is a relatively rare condition with an estimated prevalence of 1 in 100,000. It occurs most frequently in women with uncontrolled type II diabetes.

We report a case of hyperglycemic non-ketotic hemichoreaballism in a man with recently diagnosed diabetes.

A 55-year-old man presented with 2 weeks of abnormal right hemibody movements which started in the fingers, then spread to the entire right side. Movements improved with marijuana and were exacerbated by stress. His only other comorbidity was recently diagnosed diabetes and blood glucose levels was 400g/dL without anion gap. Examination demonstrated choreiform movements of his right face, arm and leg. There was also athetosis of the digits on the right hand, and intermittent hemiballismus. MRI Head demonstrated T1 hyperintensity and T2 hypointensity of the left caudate and lenticular nucleus, with extension to the left centrum semiovale. Screening tests, including blood smear, TSH, PTH, ionized calcium, CK, ceruloplasmin, ESR, ANA, AFP, HIV, B12, RPR and lipid panel were normal. Strict glycemic control did not alleviate the symptoms and hence he was started on a dopamine depletor (deutetrabenazine).

Hyperglycemic non-ketotic hemichoreaballism is a uniquely reversible abnormality of the basal ganglia occurring in the setting of uncontrolled diabetes. MRI classically demonstrate isolated putamen, or striatal hyperintensity on T1. Several etiologies have been proposed, including petechial hemorrhage, temporary ischemia (with or without hyperviscosity), or decreased synthesis of GABA and acetylcholine secondary to metabolic changes. Prior studies have demonstrated that correction of hyperglycemia often results in complete or partial resolution of these movements. However, a recent report in Nature found that up to one in four patients may also require the addition of anti-chorea medications. Striatal hyperintensities on CT and MRI resolve on average around three and eight months respectively.