Serum D-Dimer Concentrations Are Increased after Pediatric Traumatic Brain Injury

ObjectiveTo determine whether D-dimer would be increased in children with traumatic brain injury (TBI), specifically mild abusive head trauma.Study designD-dimer was measured using multiplex bead technology in 195 children <4 years old (n = 93 controls without TBI, n = 102 cases with TBI) using previously collected serum. D-dimer was then measured prospectively in a clinical setting in 44 children (n = 24 controls, n = 20 cases). Receiver operator curves were generated for prospective data.ResultsIn both the retrospective and prospective cohorts, median (25th-75th percentile) D-dimer was significantly higher in cases vs controls. A receiver operator curve demonstrated an area under the curve of 0.91 (95% CI 0.83-0.99) in the prospective cohort. At a cut-off of 0.59 μg/L, the sensitivity and specificity for identification of a case was 90% and 75%, respectively.ConclusionsOur data suggest that serum D-dimer may be able to be used to identify which young children at risk for abusive head trauma might benefit from a head computed tomography or other additional evaluation. Additional data are needed to better identify the clinical scenarios that may result in false positive or false negative D-dimer concentrations.