Hyperglycemia is a well-documented cause of neurological disorders ranging from encephalopathy to seizures and is commonly considered in patients as a potential stroke mimic. However, it very sparingly presents with focal deficits that conform to a large artery vascular distribution and as such is often overlooked as a potential focal large vessel occlusive syndrome mimic.

A 68 year-old male with a past medical history of dwarfism, atrial fibrillation, CAD, and poorly controlled DMT2 presented with encephalopathy, aphasia, right hemiparesis, and left gaze preference after a reported seizure-like event. Initial labs showed elevated blood glucose in the 600s. The initial non-contrasted CT Head did not reveal any obvious ischemia. The patient did not qualify for intravenous thrombolytic therapy since there was no clear time of symptom onset. CTA Head/Neck did not show any flow-limiting stenoses or large vessel occlusions. However, CT Perfusion revealed significantly increased time-to-peak in the entire left cerebral hemisphere without a corresponding decrease in cerebral blood volume, indicating ischemic penumbra without core infarction. MRI Brain was negative for acute ischemia. EEG demonstrated left hemispheric slowing without epileptiform activity. His hyperglycemia was treated with intravenous fluids and an insulin infusion. Once normoglycemia was achieved, his presenting neurologic deficits began to improve and returned back to baseline functional status within 72 hours. EEG findings normalized with correction of his hyperglycemia.

Our case details a hyperglycemic patient with symptoms clinically mimicking a left MCA syndrome in addition to CTP findings of left hemispheric hypoperfusion. Recognizing this etiology is imperative as it affects management and prevents unnecessary stroke interventions. Increased reporting of hyperglycemia as a large vessel occlusive stroke mimic allows for it to be better recognized and managed by future physicians. Additionally, the pathophysiology of focal deficits resulting from systemic insults is poorly understood and likewise merits further investigation.