Protein S100B and neuron-specific enolase (NSE) for the initial evaluation of mild head trauma in adults: ready for prime time?

Computerized tomography (CT) remains the best option for diagnosis of head trauma, although it carries several drawbacks. Among a large number of putative biomarkers proposed for initial evaluation of mild head trauma, protein S100B and NSE exhibit the best diagnostic performance. We performed a prospective study, where these biomarkers were assessed in 68 patients consecutively admitted to the Emergency Department (ED) with mild head trauma. The CT scan revealed brain lesions in 11 patients (16%). Concentrations of both biomarkers in serum were found to be more elevated in patients with positive CT than in those with negative scans. The area under the ROC curve (AUC) of protein S100B (0.89, 95% confidence interval: 0.81-0.97) was, however, significantly greater than that of NSE (0.77, 95% confidence interval: 0.64-0.90) (P=0.044). It was estimated that determination of protein S100B in all patients presenting to the ED with mild head trauma could safely save up to 50% CT execution, reducing the overall healthcare expenditure by 1/3.