Background: Posterior Reversible Encephalopathy (PRES) is characterized by acute-onset headache, altered mental status, cortical blindness and seizures, with parietal-occipital involvement. We report all cases of PRES diagnosed in our intensive care unit during the last 4 years, and evaluate their outcome in terms of the different medical treatments used. Even if usually reversible, PRES can sometimes result in death or irreversible neurological deficit, such as chronic epilepsy.
Material/methods: From January 2001 to January 2005, we identified 8 female patients with PRES. All patients underwent basal and follow-up brain MRI. Patients referred to Epilepsy Center (about 3000 patients) were reviewed in order to identify subjects with a clinical history of PRES. These latter were clinically re-evaluated and underwent video-EEG, MRI study and neuropsychological testing.
Results: Of the 8 patients, 5 had hypertensive encephalopathy during pregnancy; 2 had eclampsia during the postpartum period; 1 patient with chronic renal failure developed symptoms after immunosuppressive treatment. In all patients but 1, neurological and radiological abnormalities resolved after appropriate treatment. In addition, we found 2 patients with temporal lobe epilepsy subsequent to a previous PRES. MRI revealed cortical-subcortical malacia in the parietal-occipital regions.
Conclusions: The widespread use of MRI technology has made PRES familiar to many clinicians. Although PRES is reversible when treatment is instituted, delayed diagnosis and therapy can result in chronic neurological sequelae. The relationship between hypertensive encephalopathy and chronic epilepsy needs to be confirmed by longitudinal studies. Normalization of blood pressure and treatment of seizures deserves particular attention.