Diagnostic and Prognostic Significance of Serum Biomarkers in Traumatic Spinal Cord Injury: A Prospective Cohort Study

Objective: This study was conducted to analyze the association of serum biomarkers (S-100 B protein [S-100β], glial fibrillary acidic protein [GFAP], neuron-specific enolase [NSE], and phosphorylated form of neurofilament protein heavy subunit [pNF-H]) with injury severity at presentation and functional outcome at 6 months across the American Spinal Injury Association Impairment Scale (AIS) classifications, in acute traumatic spinal cord injury (SCI) patients. Methodology: A total of 26 adult acute traumatic-SCI patients with spinal-column fracture (presenting within 24 hours of injury) were recruited. The enzyme-linked immunosorbent assay technique was utilized to quantitatively assess the serum biomarkers at admission, 2 days, and 7 days after injury. Results: Day 2 GFAP serum levels >0.34 ng/ml demonstrated an association with non-functional status (AIS A-C) at admission (AUC 0.77, 95% CI 0.56–0.98; sensitivity 73.3%; specificity 80%; P = 0.07) and complete SCI (AIS A) at admission (AUC 0.76, 95% CI 0.55–0.97; sensitivity 76.9%; specificity 71.4%; P = 0.05). Day 7 GFAP serum levels >0.32 ng/ml demonstrated an association with complete SCI (AIS A) at admission (AUC 0.78, 95% CI 0.53–1.00; sensitivity 76.9%; specificity 80%; P = 0.07). Day 7 S-100β serum levels >100 pg/ml predicted the non-functional status (AIS A-C) at 6-months (AUC 0.86, 95% CI = 0.58–1.00; sensitivity 66.7%; specificity 100%; P = 0.09) and complete SCI (AIS A) at 6-months (AUC 1.00, 95% CI 1.00–1.00; sensitivity 100%; specificity 100%; P = 0.04). Conclusions: Serial monitoring of serum GFAP and S-100β levels may provide useful insights into the objective assessment of injury severity and prognostication of acute traumatic SCI patients.