Serum S100B determination in the management of pediatric mild traumatic brain injury.

BACKGROUND The place of serum S100B measurement in mild traumatic brain injury (mTBI) management is still controversial. Our prospective study aimed to evaluate its utility in the largest child cohort described to date. METHODS Children younger than 16 years presenting at a pediatric emergency department within 3 h after TBI were enrolled prospectively for blood sampling to determine serum S100B concentrations. The following information was collected: TBI severity determined by using the Masters classification [1: minimal or Glasgow Coma Scale (GCS) 15, 2: mild or GCS 13-15, and 3: severe or GCS <13]; whether hospitalized or not; good or bad clinical evolution (CE); whether cranial computed tomography (CCT) was prescribed; and related presence (CCT+) or absence (CCT-) of lesions. RESULTS For the 446 children enrolled, the median concentrations of S100B were 0.21, 0.31, and 0.44 μg/L in Masters groups 1, 2, and 3, respectively, with a statistically significant difference between these groups (P < 0.05). In Masters group 2, 65 CCT scans were carried out. Measurement of S100B identified patients as CCT+ with 100% (95% CI 85-100) sensitivity and 33% (95% CI 20-50) specificity. Of the 424 children scored Masters 1 or 2, 21 presented "bad CE." S100B identified bad CE patients with 100% (95% CI 84-100) sensitivity and 36% (95% CI 31-41) specificity. Of the 242 children hospitalized, 81 presented an S100B concentration within the reference interval. CONCLUSIONS Serum S100B determination during the first 3 h of management of children with mTBI has the potential to reduce the number of CCT scans, thereby avoiding unnecessary irradiation, and to save hospitalization costs.