title: The prognostic value of serum neuron-specific enolase in traumatic brain injury: systematic review and meta-analysis.
abstract: BACKGROUND
  Several studies have suggested that neuron-specific enolase (NSE) in serum may be a biomarker of traumatic brain injury. However, whether serum NSE levels correlate with outcomes remains unclear. The purpose of this review was to evaluate the prognostic value of serum NSE protein after traumatic brain injury.
  
  
  METHODS
  PubMed and Embase were searched for relevant studies published up to October 2013. Full-text publications on the relationship of NSE to TBI were included if the studies concerned patients with closed head injury, NSE levels in serum after injury, and Glasgow Outcome Scale (GOS) or Extended GOS (GOSE) scores or mortality. Study design, inclusion criteria, assay, blood sample collection time, NSE cutoff, sensitivity and specificity of NSE for mortality prediction (if sufficient information was provided to calculate these values), and main outcomes were recorded.
  
  
  RESULTS
  Sixteen studies were eligible for the current meta-analysis. In the six studies comparing NSE concentrations between TBI patients who died and those who survived, NSE concentrations correlated with mortality (M.D. 0.28, 95% confidence interval (CI), 0.21 to 0.34; I2 55%). In the eight studies evaluating GOS or GOSE, patients with unfavorable outcomes had significantly higher NSE concentrations than those with favorable outcomes (M.D. 0.24, 95% CI, 0.17 to 0.31; I2 64%). From the studies providing sufficient data, the pooled sensitivity and specificity for mortality were 0.79 and 0.50, and 0.72 and 0.66 for unfavorable neurological prognosis, respectively. The areas under the SROC curve (AUC) of NSE concentrations were 0.73 (95% CI, 0.66-0.80) for unfavorable outcome and 0.76 (95% CI, 0.62-0.90) for mortality.
  
  
  CONCLUSIONS
  Mortality and unfavorable outcome were significantly associated with greater NSE concentrations. In addition, NSE has moderate discriminatory ability to predict mortality and neurological outcome in TBI patients. The optimal discrimination cutoff values and optimal sampling time remain uncertain because of significant variations between studies.
authors.affiliation: Department of Neurosurgery, The First People's Hospital of Kunshan, affiliated with Jiangsu University, Suzhou, PR China.
authors.forename: Feng
authors.initials: F
authors.lastname: Cheng
authors.affiliation: Department of Neurosurgery, Huashan Hospital, affiliated to Fudan University, Shanghai, PR China.
authors.forename: Qiang
authors.initials: Q
authors.lastname: Yuan
authors.affiliation: Department of Neurosurgery, The First People's Hospital of Kunshan, affiliated with Jiangsu University, Suzhou, PR China.
authors.forename: Jian
authors.initials: J
authors.lastname: Yang
authors.affiliation: Department of Neurosurgery, The First People's Hospital of Kunshan, affiliated with Jiangsu University, Suzhou, PR China.
authors.forename: Wenming
authors.initials: W
authors.lastname: Wang
authors.affiliation: Department of Neurosurgery, The First People's Hospital of Kunshan, affiliated with Jiangsu University, Suzhou, PR China.
authors.forename: Hua
authors.initials: H
authors.lastname: Liu
mesh_terms: D001930:Brain Injuries / Q000097:blood* / Q000473:pathology*; D006801:Humans; D010751:Phosphopyruvate Hydratase / Q000097:blood*; D011379:Prognosis
chemical_list: D010751:Phosphopyruvate Hydratase