Posterior Reversible Encephalopathy Syndrome in an Elderly Man: A Case Report

Posterior reversible encephalopathy syndrome (PRES) is a clinico-radiological entity characterized by the acute or subacute onset of neurological symptoms such as headache, seizures, visual disturbances, focal neurological deficits, and signs of encephalopathy. It is a syndrome with increasing recognition, largely due to the greater availability and utilization of neuroimaging techniques. We report the clinical case of a 74-year-old Caucasian male with a medical history of diabetes mellitus and obesity, whose main risk factor was arterial hypertension. He was admitted to the emergency department presenting with headache, mental confusion, speech disturbance, and decreased visual acuity, with one day of symptom progression. On admission, he was hypertensive (160/70 mmHg), somnolent but easily arousable, with disorganized speech and a Glasgow Coma Scale score of 12. Initial laboratory investigations showed no significant abnormalities. Cranial computed tomography revealed bilateral hypodense areas in the temporo-occipital regions, more pronounced on the left, with additional involvement of the anterior temporal and parietal lobes. Brain magnetic resonance imaging confirmed the presence of vasogenic edema, consistent with PRES. The patient remained hospitalized for clinical monitoring and blood pressure control, as well as further diagnostic workup. He showed marked clinical improvement, with complete resolution of symptoms within one week. Through this case report, we seek to underscore the importance for clinicians of considering PRES in the differential diagnosis of acute neurological presentations, even in patients without severe arterial hypertension or other commonly associated risk factors.