RESUMO
BACKGROUND: Subacute hemichorea-hemiballismus in an older patient can be induced by non-ketotic hyperglycaemia. The triad of onset of subacute hemichorea-hemiballismus, hyperglycaemia and hyperdensity in the contralateral putamen on a CT scan or hyperintensity on a T1-weighted MRI scan is pathognomic for this diagnosis. Close observation of the motor restlessness and knowledge of this triad are important for making this diagnosis. CASE DESCRIPTION: A 92-year-old female patient was admitted to the accident and emergency department with a history of motor restlessness for the past few days, confused speech and a glucose level of 20.5 mmol/l. Delirium was initially suspected. Abnormalities on the CT scan were indicative of hemichorea-hemiballismus caused by hyperglycaemia. The patient recovered fully once euglycaemic levels were restored. CONCLUSION: Hemichorea-hemiballismus is a rare motor disorder, often due to an infarct in the contralateral basal ganglia. It can, however, be an expression of non-ketotic hyperglycaemia. The condition is sometimes confused with the motor restlessness of delirium.