Hemichorea: A Rare Neurological Complication of Diabetes Mellitus

Diabetes mellitus is a prevalent metabolic disorder that has a wide range of complications. Neurological complications are common and include stroke and peripheral neuropathy. However, hemichorea is a very rare manifestation of diabetes mellitus. Chorea can be due to primary inherited conditions or secondary to other disorders. Careful evaluation of patients with chorea is crucial since secondary chorea can be managed with the treatment of the underlying cause. We report the case of a 51-year-old man who presented to the emergency department with a two-week history of sudden involuntary and random-appearing movements of the right upper and lower extremities. These movements were non-suppressible and disappeared during sleep. Further, the movements were not associated with any neurological symptoms, including headache, dizziness, weakness, sensory deficits, or loss of consciousness. The patient had a longstanding history of hypertension and diabetes mellitus. He reported that he was not compliant with his medications. Laboratory investigation revealed a very high level of blood glucose (580 mg/dL) with associated pseudohyponatreamia (127 mEq/L). Head computed tomography scan showed increased density in right caudate nuclei and putamen with no surrounding edema or mass effect. The findings were suggestive of non-ketotic hyperglycemic hemichorea based on the clinical, laboratory, and radiological laboratory findings. The patient received insulin therapy according to sliding-scale protocol. The chorea movements gradually improved and completely disappeared after the fourth day of admission with the normalization of glucose level. In view of this, emergency medicine physicians should consider non-ketotic hyperglycemia as a potential underlying etiology of acute hemichorea.