Glial Fibrillary Acidic Protein as a Biomarker in Acute Ischemic Stroke: Diagnostic Value and Prognostic Implications

Stroke is one of the leading causes of mortality and long-term disability worldwide, with ischemic stroke representing the most common subtype.Despite significant progress in neuroimaging and reperfusion therapies, rapid and accurate diagnosis remains a major challenge in clinical practice.Glial fibrillary acidic protein, an intermediate filament protein specific to astrocytes, has recently gained attention as a promising blood-based biomarker.Following astrocytic damage and disruption of the blood-brain barrier, glial fibrillary acidic protein is released into the extracellular space and enters the circulation.Although its levels rise rapidly in hemorrhagic stroke, the increase in ischemic stroke occurs more gradually, typically becoming measurable within the first 24 to 48 hours after the onset of symptoms.Clinical investigations have demonstrated that blood concentrations of glial fibrillary acidic protein are significantly higher in patients with ischemic stroke compared to healthy controls and that these elevations correlate with neurological severity, infarct volume, and functional outcomes.Thus, glial fibrillary acidic protein provides valuable prognostic insights and may support patient stratification.However, variability in cut-off values, differences in detection methods, and delayed kinetics remain important limitations.Future developments include the integration of glial fibrillary acidic protein into multimarker panels and the use of ultrasensitive point-of-care assays that may enable rapid decision-making in emergency settings.Overall, glial fibrillary acidic protein has the potential to serve as a complementary biomarker for diagnosis, prognosis, and monitoring in ischemic stroke, thereby contributing to improved patient care and individualized therapeutic strategies.