Acute Focal Dystonia as a Presentation of Uncontrolled Hyperglycemia.

Hyperglycemia-induced involuntary movements (HIIM) include tremors, hemichorea-hemiballismus (HCHB), and more rarely, dystonia. Presentations may vary, but hyperintensity involving the basal ganglia area on the T1 sequence of MRI brain remains a commonality.  We report the occurrence of focal dystonia with uncontrolled hyperglycemia but no focal abnormalities on MRI. On admission, the patient's blood glucose was 861, and she claimed to have never missed insulin dosage. A physical exam revealed no cranial nerve abnormalities and weakness in the right upper extremity with no sensory involvement. Reflexes were 1-2+ in all extremities with down-going toes. The abnormal movements were triggered by overhead abduction of the right arm. Symptoms improved after a week with blood glucose control, as well as benzodiazepines and anticholinergics. This specific case emphasizes the occurrence of uncontrolled hyperglycemia causing movement disorders that can have normal imaging findings. Understanding the complex presentation of patients with HIIM is pivotal for effective patient diagnosis and treatment.