Dynamics of glial fibrillary acidic protein during traumatic brain injury in children.

Backgrounds: Glial fibrillary acidic protein (GFAP) is a monomeric intermediate filament protein found in the astroglial cytoskeleton and is not found outside the central nervous system. It is a brain-specific protein that is released after traumatic brain injury (TBI).

Methods: This prospective study enrolled 59 children who had TBI, as verified by computed tomography. Daily GFAP measurement began at admission (<12 hours after trauma) and continued for 6 days. Blood samples were analyzed for GFAP by enzyme-linked immunosorbent assay. Outcome was assessed using the Glasgow Outcome Scale (GOS) at 6 months after injury.

Results: The median serum levels of GFAP at admission were 7.47 ng/mL in patients who died, compared with 0.12 ng/mL in patients who survived (p=0.002). GFAP levels were significantly higher in patients who had a poor outcome 6 months after injury than in those who were alive or had good outcome (p<0.001). The area under the receiver operating characteristic curve for GFAP was 0.833 for day 0 and 0.884 for day 2.

Conclusions: These results suggest that determination of serum levels of GFAP may add to the clinical assessment of the primary damage and prediction of outcome after severe TBI.