To explore the diagnostic characteristics of hemichorea associated with non-ketotic hyperglycemia (HC-NH).

A retrospective analysis of the clinical data of a patient with HC-NH admitted to the Psychology Department of Affiliated Hospital of Guizhou Medical University on November 10, 2019, and relevant literatures were reviewed.

A 64-year-old male patient was admitted to the hospital for involuntary movement of the right limb for more than 10 days. The clinical manifestations were hemichorea-like movements, increased blood sugar, and negative urine ketones. Brain magnetic resonance imaging (MRI) T₁WI showed abnormally high signal in the left basal ganglia region. The patient was diagnosed with HC-NH, and the blood glucose was actively controlled. After treatment with haloperidol and clonazepam, the patient′s chorea-like symptoms disappeared. Followed up for 3 months, brain CT reexamination showed that the lesions shrunk, and the condition was stable without recurrence so far.

Chorea-like symptoms, high blood sugar, negative urine ketones, abnormal signal in the basal ganglia region in brain MRI, are important diagnostic features of HC-NH, which could be improved after blood glucose control, sedation and antipsychotic treatment.