It is not unusual to observe hemichorea in patients with
diabetes mellitus, with origins attributable to recent
ischemia. Our patient was a 66-year-old female with
diabetes mellitus who suddenly developed right hemichorea, mild
muscle weakness of the right upper extremity,
ideational apraxia, and
acalculia. Her
blood glucose was 600 mg/dL, and HbA1c was 13.3%. After the patient underwent head magnetic resonance imaging (MRI), a new
cerebral infarction was observed in the left frontal lobe, and treatment was started with
edaravone and
cilostazol. At the same time,
insulin treatment was also started for
hyperglycemia. The
acalculia and
ideational apraxia improved approximately 1 week
after treatment initiated, and the hemichorea also decreased. ECD-SPECT was performed on admission, and it was observed that blood flow was decreased in the left frontal lobe and striatum, but increased in the thalamus; two weeks later on follow-up ECD-SPECT, blood flow had increased slightly in the left forebrain and striatum, while it had decreased slightly in the thalamus. This suggests that the cause of hemichorea was related to
ischemia. When the activity of the pallidum is impaired, it is presumed that the inhibitory activity towards the thalamus weakens and the thalamic cells become over-excited, causing
chorea.