Hemichorea-Hemiballismus as the First Sign of Type 1b Diabetes During Adolescence and Its Recurrence in the Setting of Infection.

Chorea may be secondary to hyperosmolar nonketotic hyperglycemia, but such situation has rarely been described in adolescents, particularly as the initial and single manifestation of type 1 diabetes. We describe a case of a previously healthy 14-year-old girl with sudden onset of choreic movements on her left upper and lower limbs. Brain computed tomography (CT) and magnetic resonance imaging (MRI) revealed an area of hyperdensity/hyperintensity affecting the right striatum. Blood glucose was 349 mg/dL. Despite adequate glucose control, the involuntary movements persisted and haloperidol, later substituted with valproate, was prescribed, with satisfactory but not complete resolution of the chorea. In 2 other occasions, when the patient had an infection and subsequent hyperglycemia, the chorea relapsed. Although not common, hyperglycemia must be considered in the differential diagnosis of acute hemichorea-hemiballismus in children and adolescents, particularly because it is a potentially reversible cause.