Posterior Reversible Encephalopathy Syndrome: A Narrative Review for Emergency Clinicians

Posterior reversible encephalopathy syndrome (PRES) is a clinicoradiologic disorder characterized by seizures, headache, altered mental status, and visual disturbances, and is often associated with acute hypertension.

This narrative review provides a focused description of the presentation, diagnostic evaluation, and management of PRES.

PRES is associated with a variety of factors, including acute rise in blood pressure, renal disease, preeclampsia/eclampsia, and immunosuppressive therapy. The pathophysiology is theorized to involve dysfunction of cerebral autoregulation leading to vascular leak or endothelial dysfunction resulting in vasogenic edema. In the emergency department (ED), clinical findings suggestive of PRES should prompt diagnostic testing focused on confirming the diagnosis and excluding other conditions that may present similarly. Laboratory studies are primarily useful for excluding alternative diagnoses. Computed tomography (CT) and, in particular, magnetic resonance imaging (MRI) are the recommended neuroimaging modalities for diagnosis. CT and MRI may demonstrate cerebral vasogenic edema, most often in the distribution of the posterior circulation. Treatment involves management of seizures, control of blood pressure if elevated, and treatment of any underlying trigger.

PRES is a neurological disorder that is typically reversible if recognized on presentation and promptly and appropriately managed. This narrative review characterizes this condition for emergency clinicians.