A Stroke Mimic Driven by Fear: Nonketotic Hyperglycemic Hemichorea in a Patient With Needle Phobia.

Nonketotic hyperglycemic hemichorea, also known as diabetic striatopathy, is a rare but reversible neurological complication of poorly controlled diabetes mellitus that can mimic acute cerebrovascular events. We report a case of an elderly woman with poorly controlled type 2 diabetes mellitus (glycated hemoglobin (HbA1c) 12.6%) who presented with a 2-week history of progressive, involuntary movements involving the left upper and lower extremities. The movements were continuous, non-suppressible, and consistent with hemichorea. Laboratory evaluation revealed severe hyperglycemia (glucose >500 mg/dL), normal serum osmolality (295 mOsm/kg), and negative ketones, confirming a nonketotic state. Non-contrast computed tomography of the head demonstrated hyperdensity of the right caudate and putamen. Magnetic resonance imaging showed T1-weighted hyperintensity involving the right basal ganglia. The differential diagnosis included acute stroke and neurodegenerative etiologies; however, clinical and radiologic findings supported diabetic striatopathy. The patient was treated with intravenous fluids and insulin therapy, resulting in rapid glycemic control and significant improvement in symptoms without the need for neuroleptic agents. At the three-month follow-up, she demonstrated near-complete clinical resolution, with repeat imaging confirming near-complete resolution of prior abnormalities. This case highlights nonketotic hyperglycemic hemichorea as a reversible stroke mimic and underscores the importance of early recognition and glycemic control. It also emphasizes how behavioral factors, such as needle phobia, can contribute to poor disease control and lead to significant neurological complications.