Posterior Reversible Encephalopathy Syndrome in the Postpartum Period: A Rare Entity With Atypical Presentation.

Posterior reversible encephalopathy syndrome (PRES) is a rare condition characterized by clinical and brain imaging criteria. It is most often associated with pregnancy in the postpartum period and has a higher incidence in primiparous patients. Its presentation includes headaches, altered consciousness, seizures, visual disturbances, and specific radiological signs, particularly vasogenic edema of the subcortical white matter, primarily located in the posterior cerebral hemispheres. While PRES in obstetrics is most commonly associated with preeclampsia or, more frequently, eclampsia, we report a case occurring in a normotensive patient. Our case involves a primiparous patient in the postpartum period who presented with a wide range of severe neurological symptoms, including transient cortical blindness and severe memory loss correlated to lesions in atypical regions, such as the temporal lobes and bilateral hippocampi and thalami. The distribution of lesions, the apparent diffusion coefficient (ADC) and diffusion-weighted imaging (DWI) MRI mapping allowed a differentiation of PRES from early cerebral ischemia, thus playing an essential role in management. This case highlights the need to consider PRES in postpartum patients with significant neurological symptoms, regardless of blood pressure or proteinuria status. Early recognition and diagnosis are essential for optimal outcomes, given the reversible nature of the syndrome with timely intervention.