title: The Levels of Glial Fibrillary Acidic Protein and Ubiquitin C-Terminal Hydrolase-L1 During the First Week After a Traumatic Brain Injury: Correlations With Clinical and Imaging Findings.
abstract: Glial fibrillary acidic protein (GFAP) and ubiquitin C-terminal hydrolase-L1 (UCH-L1) are promising biomarkers of traumatic brain injury (TBI).
  
  
  
  We investigated the relation of the GFAP and UCH-L1 levels to the severity of TBI during the first week after injury.
  
  
  
  Plasma UCH-L1 and GFAP were measured from 324 consecutive patients with acute TBI and 81 control subject enrolled in a 2-center prospective study. The baseline measures included initial Glasgow Coma Scale (GCS), head computed tomographic (CT) scan at admission, and blood samples for protein biomarkers that were collected at admission and on days 1, 2, 3, and 7 after injury.
  
  
  
  Plasma levels of GFAP and UCH-L1 during the first 2 days after the injury strongly correlated with the initial severity of TBI as assessed with GCS. Additionally, levels of UCH-L1 on the seventh day after the injury were significantly related to the admission GCS scores. At admission, both biomarkers were capable of distinguishing mass lesions from diffuse injuries in CT, and the area under the curve of the receiver-operating characteristic curve for prediction of any pathological finding in CT was 0.739 (95% confidence interval, 0.636-0.815) and 0.621 (95% confidence interval, 0.517-0.713) for GFAP and UCH-L1, respectively.
  
  
  
  These results support the prior findings of the potential role of GFAP and UCH-L1 in acute-phase diagnostics of TBI. The novel finding is that levels of GFAP and UCH-L1 correlated with the initial severity of TBI during the first 2 days after the injury, thus enabling a window for TBI diagnostics with latency.
  
  
  
  AUC, area under the curveCI, confidence intervalED, emergency departmentGCS, Glasgow Coma ScaleGRAP, glial fibrillary acidic proteinIMPACT, International Mission for Prognosis and Clinical TrialROC, receiver-operating characteristicTBI, traumatic brain injuryTRACK-TBI, Transforming Research and Clinical Knowledge in Traumatic Brain InjuryUCH-L1, ubiquitin C-terminal hydrolase-L1.
authors.affiliation: *Division of Clinical Neurosciences, Department of Neurosurgery and ‡Division of Clinical Neurosciences, Department of Rehabilitation and Brain Trauma, Turku University Hospital, Turku, Finland; §Department of Neurology, University of Turku, Turku, Finland; ¶Perioperative Services, Intensive Care Medicine and Pain Management, Turku University Hospital and University of Turku, Turku, Finland; ‖Systems Medicine, VTT Technical Research Centre of Finland, Tampere, Finland; #Division of Anaesthesia, Department of Medicine and **Department of Clinical Neurosciences, Neurosurgery Unit, University of Cambridge, Addenbrooke's Hospital, Cambridge, United Kingdom.
authors.forename: Jussi P
authors.initials: JP
authors.lastname: Posti
authors.forename: Riikka S K
authors.initials: RS
authors.lastname: Takala
authors.forename: Hilkka
authors.initials: H
authors.lastname: Runtti
authors.forename: Virginia F
authors.initials: VF
authors.lastname: Newcombe
authors.forename: Joanne
authors.initials: J
authors.lastname: Outtrim
authors.forename: Ari J
authors.initials: AJ
authors.lastname: Katila
authors.forename: Janek
authors.initials: J
authors.lastname: Frantzén
authors.forename: Henna
authors.initials: H
authors.lastname: Ala-Seppälä
authors.forename: Jonathan P
authors.initials: JP
authors.lastname: Coles
authors.forename: Md Iftakher
authors.initials: MI
authors.lastname: Hossain
authors.forename: Anna
authors.initials: A
authors.lastname: Kyllönen
authors.forename: Henna-Riikka
authors.initials: HR
authors.lastname: Maanpää
authors.forename: Jussi
authors.initials: J
authors.lastname: Tallus
authors.forename: Peter J
authors.initials: PJ
authors.lastname: Hutchinson
authors.forename: Mark
authors.initials: M
authors.lastname: van Gils
authors.forename: David K
authors.initials: DK
authors.lastname: Menon
authors.forename: Olli
authors.initials: O
authors.lastname: Tenovuo
mesh_terms: D000328:Adult; D000368:Aged; D015415:Biomarkers / Q000097:blood*; D000070642:Brain Injuries, Traumatic / Q000097:blood* / Q000175:diagnosis*; D005260:Female; D015600:Glasgow Coma Scale; D005904:Glial Fibrillary Acidic Protein / Q000097:blood*; D006801:Humans; D008297:Male; D008875:Middle Aged; D011379:Prognosis; D011446:Prospective Studies; D012372:ROC Curve; D043222:Ubiquitin Thiolesterase / Q000097:blood*
chemical_list: D015415:Biomarkers; D005904:Glial Fibrillary Acidic Protein; D043222:Ubiquitin Thiolesterase