The Role of GFAP in Post-Mortem Analysis of Traumatic Brain Injury: A Systematic Review.

Traumatic brain injuries (TBIs) are a leading cause of mortality and morbidity, particularly in forensic settings where determining the cause of death and timing of injury is critical. Glial fibrillary acidic protein (GFAP), a biomarker specific to astrocytes, has emerged as a valuable tool in post-mortem analyses of TBI. A PRISMA-based literature search included studies examining GFAP in human post-mortem samples such as brain tissue, cerebrospinal fluid (CSF), serum, and urine. The results highlight that GFAP levels correlate with the severity of brain injury, survival interval, and pathological processes such as astrocyte damage and blood-brain barrier disruption. Immunohistochemistry, ELISA, and molecular techniques were commonly employed for GFAP analysis, with notable variability in protocols and thresholds among studies. GFAP demonstrated high diagnostic accuracy in distinguishing TBI-related deaths from other causes, particularly when analyzed in CSF and serum. Furthermore, emerging evidence supports its role in complementing other biomarkers, such as S100B and NFL, to improve diagnostic precision. However, the review also identifies significant methodological heterogeneity and gaps in standardization, which limit the generalizability of findings. Future research should focus on establishing standardized protocols, exploring biomarker combinations, and utilizing advanced molecular tools to enhance the forensic application of GFAP.