Title : TBI biomarkers
Abstract:
Background: Mild traumatic brain injury (mTBI) represents the majority of traumatic brain injuries evaluated in emergency departments. Although computed tomography (CT) remains the reference standard for detecting intracranial lesions, its routine use contributes to unnecessary radiation exposure, increased healthcare costs, and emergency department overcrowding. Blood-based biomarkers have emerged as promising tools to improve diagnostic accuracy and optimize patient triage.
Objective: To systematically evaluate the diagnostic and prognostic performance of the serum biomarkers glial fibrillary acidic protein (GFAP), ubiquitin C-terminal hydrolase-L1 (UCH-L1), and S100 calcium-binding protein B (S100B) in patients with mild traumatic brain injury.
Methods: A systematic review was conducted according to the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. PubMed/MEDLINE, Embase, and Scopus were searched for studies evaluating serum biomarkers in adult patients with mTBI. Eligible studies assessed biomarker concentrations in relation to CT findings, neurosurgical intervention, and clinical outcomes. Data regarding study characteristics, biomarker performance, and diagnostic accuracy were extracted and qualitatively synthesized.
Results: Eight studies comprising more than 5,000 patients met the inclusion criteria. GFAP consistently demonstrated the highest diagnostic performance for detecting CT-positive intracranial injuries, remaining informative for up to 72 hours after trauma. UCH-L1 showed greater sensitivity during the early post-injury period, particularly within the first hours after trauma, while S100B demonstrated prognostic value but lower specificity because of extracranial sources. Several studies reported that combining GFAP and UCH-L1 improved discrimination between CT-positive and CT-negative patients, suggesting a potential reduction in unnecessary CT imaging without compromising patient safety.
Conclusions: Current evidence supports GFAP as the most robust serum biomarker for identifying clinically significant intracranial injury after mild traumatic brain injury. Combined biomarker strategies, particularly GFAP and UCH-L1, may improve emergency department decision-making, reduce unnecessary imaging, and facilitate early risk stratification. Additional prospective multicenter studies are warranted to establish standardized cutoff values and support broader clinical implementation.
