Posterior Reversible Encephalopathy Syndrome (PRES) in an Elderly Patient with Parkinson's Disease and Blood Pressure Fluctuations: A Case Report

Posterior Reversible Encephalopathy Syndrome (PRES) is a neurological disorder defined by headache, altered mental status, seizures, and visual disturbances, coupled with neuroimaging showing vasogenic edema mainly in the parieto-occipital regions. Blood pressure fluctuation is common in Parkinson’s disease (PD) due to autonomic dysfunction affecting blood pressure regulation. Additionally, PD medications may contribute to episodes of both low and high blood pressure. We report an 82-year-old female with longstanding PD who presented with decreased consciousness and unsteadiness, and whose MRI was characteristic of PRES. She had a history of fluctuating blood pressure with diurnal variation, a recognised autonomic dysfunction in PD. This case underscores a possible association between PD-related autonomic dysfunction and PRES. With appropriate blood pressure control, the patient improved clinically and radiologically. This report also briefly reviews PRES in elderly patients, autonomic dysfunction in PD, and management considerations in such complex cases.