Intracranial hemorrhage in posterior reversible encephalopathy syndrome: a systematic review and meta-analysis.

Background: Posterior reversible encephalopathy syndrome (PRES) is a clinical-radiographic phenomenon characterized by vasogenic edema, predominantly affecting the posterior regions of the brain. The hemorrhagic variant of PRES has been increasingly recognized, complicating the clinical picture and prognosis. Methods: This meta-analysis was conducted in accordance with Preferred Reporting Items for Systematic Reviews and Meta-Analyses guidelines. Observational studies and case reports/series were included. Extracted data included demographics, clinical presentations, imaging findings, and outcomes. A random-effects model to pool the incidence rate of hemorrhagic PRES and heterogeneity was assessed using the I Results: A total of 63 individual records and 12 cohort studies were reviewed. Hypertension at arrival was seen in > 90% of cases. Overall, 60.3% of cases occurred in women and the average age was 39.3, with a 12.7% mortality rate. The incidence rate of hemorrhagic PRES was found to be approximately 17%, with significant heterogeneity among the included studies (I Conclusions: Hemorrhagic PRES is a significant clinical concern, occurring in approximately 17% of PRES cases, and is often associated with poorer outcomes. We highlight the importance of early recognition, aggressive blood pressure control, and careful monitoring in high-risk patients.