Reference values for venous and capillary S100B in children

BackgroundThe current management guidelines for pediatric mild head injury (MHI) liberally recommend computed tomography (CT) and frequent admission. Serum protein S100B, currently used in management of adult head injury, has recently shown potential for reducing unnecessary CT scans after pediatric mild head injury. Capillary sampling in children is commonly used when venous sampling fails or is inappropriate. We present reference values for both venous and capillary samples of protein S100B in children.MethodsNeurologically healthy children aged 1–16, scheduled for minor surgery requiring general anesthesia, were prospectively included. Samples for S100B were drawn before (venous) and after (venous and capillary) sedation.ResultsSerum values of 455 children (255 boys, 200 girls) aged 1–14 were computed. S100B was higher in younger children for both venous (r = ? 0.32) and capillary samples (r = ? 0.28). Reference levels for children aged 1 and 2 were significantly higher than for children aged 3–14 years (venous 0.15 μg/L, capillary 0.37 μg/L). For capillary blood, a gender difference was found in the youngest age groups.ConclusionsWe present reference values for venous and capillary S100B in healthy children. These results can be utilized when considering future studies on pediatric head injury and S100B levels.