Abstract 370: Posterior Reversible Encephalopathy Syndrome (PRES): Illustrative Case Report Highlighting Central PRES

Introduction/PurposeThe purpose of this report is to describe a suspected case of Central‐variant posterior reversible encephalopathy syndrome (PRES) mimicking a stroke in the setting of cardiac risk factors. Central PRES is cited to be only 4% of total cases of PRES.Materials/MethodsChart review of one patient at a single institution.ResultsPatient is a 48‐year‐old female with relevant past medical history of patent foramen ovale, carotid endarterectomy, tobacco use, hypertension, migraine, and hyperlipidemia who presented to the ED with acute left sided weakness starting earlier that day, severe hypertension, and severe headache. Computed Tomography (CT) head was negative for ischemic stroke or hemorrhage. Arterial CT showed neither a proximal large vessel occlusion, nor major stenosis of the arterial posterior and anterior circulation. Axial FLAIR MRI showed hyperintensities in the right basal ganglia, right thalamus, and adjacent periatrial white matter and right anterior temporal lobe. An additional small lesion was found on the pons. Patient declined TPA on presentation in hospital, and was discharged with titrated blood pressure medications. A follow‐up MRI seven months later (Figure 1) after initial presentation demonstrated interval improvement of abnormal T2‐signal intensity on pons and thalamus. Follow‐up CTA of head and neck displayed no occlusion of large vessels, but found high‐grade stenosis of the right vertebral artery near its origin.ConclusionPosterior reversible encephalopathy syndrome (PRES) is a neurological disease of exclusion often triggered by severe systemic hypertension, toxic exposure, specific medications, severe metabolic disturbance, sepsis, or conditions such as preeclampsia that can present with headache, acutely altered consciousness, seizures, visual disturbance, and confusion. Key differentials to rule out include stroke, hemorrhage, Bickerstaff's brainstem encephalitis, demyelinating conditions, and hypoglycemia. PRES is believed to be caused either by an overwhelmed posterior brain vasculature in response to elevated blood pressure, causing vasogenic edema, or from a compromised endothelial barrier. To our knowledge, this patient had no history of medication use or conditions typically associated with a chronic neuroinflammatory state. As per its name, PRES most commonly affects the bilateral posterior occipitoparietal lobes, and by definition is reversible both symptomatically and on imaging. Given the clinical findi