Abstract
Posterior reversible encephalopathy syndrome, or PRES, is often an unrecognized sequela of uncontrolled hypertension that is associated with a significant risk of mortality. It is poorly understood and can lead to endothelial dysfunction with disturbance of the blood–brain barrier and subsequent brain edema. Headache, seizures, encephalopathy, and visual disturbances are among the most common symptoms associated with PRES. Testing and evaluation should be quickly initiated not only to solidify the diagnosis but also to rule out others such as infection or stroke. Prompt identification of the symptoms of PRES can potentially reverse long-term side effects such as life-long seizures or visual deficits.