Posterior reversible encephalopathy syndrome: A case report

Posterior Reversible Encephalopathy Syndrome (PRES) is a radio-clinical entity associating reversible damage of the central nervous system and typical brain imaging. The clinical context is often suggestive with, in half of cases, the use of vasoactive substances (cannabis, antidepressants, nasal decongestants) and/or postpartum. The etiologies are dominated by hypertensive encephalopathy, preeclampsia, eclampsia, immunosuppressive therapies, and systemic diseases. We report a case of posterior encephalopathy syndrome occurring in a young female without hypertension. It was about a 40-year-old female without hypertension underlying condition, received at the emergency department for headaches and generalized tonic-clonic seizures. The physical examination was unremarkable, and her blood pressure was 130/70 mm Hg. CT scan revealed bilateral white matter hypodensity in the posterior occipital regions and a right frontal subarachnoid hemorrhage. There was no aneurysmal malformation of the polygon of Willis and no cerebral thrombophlebitis. Brain MRI showed T2 and FLAIR hypersignal areas in the occipital and frontal cortico-subcortical regions, with no diffusion signal abnormalities or contrast enhancement, and a right frontal subarachnoid hemorrhagic lesion with no other impairment. The diagnosis of reversible posterior encephalopathy syndrome was made up, and the outcome was favorable under treatment. Posterior reversible encephalopathy syndrome is an uncommon but probably underdiagnosed condition. Hypertensive encephalopathy is the most common etiology. However, there would be cases of PRES without hypertension as shown in this observation.