Serum neuron-specific enolase as a predictor of short-term outcome in children with closed traumatic brain injury

Background: Closed traumatic brain injury (cTBI) is a significant cause of mortality and morbidity in children. The natural course and extent of recovery from cTBI in children are poorly understood. Neuron-specific enolase (NSE), an enzyme detected in serum following structural damage of neuronal brain cells, appears to be a good marker for intracranial injury. However, to the best of the authors' knowledge, the usefulness of NSE as a predictor of disability in children with cTBI has not been reported. Objectives: To examine the association between posttraumatic serum NSE level and short-term physical disability in children with cTBI. Methods: This was a retrospective analysis of a prospectively enrolled cohort of children aged 0-18 years with isolated cTBI presenting to the emergency department (ED) within 24 hours of injury, and having a cranial computed tomography (CT) scan as part of the evaluation. The NSE level was obtained at the time of ED evaluation. Physical disability was measured using the Glasgow Outcome Scale (GOS). The GOS score was assigned retrospectively for enrolled patients by a single investigator blinded to NSE level. Patient outcomes were categorized as good (GOS = 5) or poor (GOS < 5). A single radiologist reviewed all cranial CT scans. Results: Ninety eligible subjects with NSE levels were identified; 86 met the enrollment criteria. Seven subjects (8%) had poor outcome. There was a significant difference in NSE levels between the poor and good outcome groups, even within high-risk subgroups. The area under the curve (AUC) for NSE prediction of poor vs. good outcome was 0.83. A serum NSE level of 21.2 ng/dL was 86% sensitive and 74% specific in predicting poor outcome. Conclusions: It appears that the serum NSE level can be used as a predictor of global short-term physical disability in children following cTBI.