腦創傷血液標記: glial fibrillary acidic protein breakdown products (GFAP-BDP)

Blood test to detect traumatic brain injury could reduce unnecessary CT scans May 18, 2015Blood test to detect traumatic brain injury could reduce unnecessary CT scans Credit: Mary Ann Liebert, Inc., publishers New study results show that a simple blood test to measure brain-specific proteins released after a person suffers a traumatic brain injury (TBI) can reliably predict both evidence of TBI on radiographic imaging and injury severity. The potential benefit of adding detection of glial fibrillary acidic protein breakdown products (GFAP-BDP) to clinical screening with computed tomography (CT) and magnetic resonance imaging (MRI) is described in an article published in Journal of Neurotrauma. Paul McMahon, University of Pittsburgh Medical Center, and a team of international researchers, including TRACK-TBI investigators, analyzed blood levels of GFAP-BDP from patients ages 16-93 years treated at multiple trauma centers for suspected TBI. They evaluated the ability of the blood-based biomarker to predict intracranial injury as compared to the findings on an admission CT and a delayed MRI scan. The authors reported a net benefit for the use of GFAP-BDP above imaging-based screening alone and a net reduction in unnecessary scans by 12-30% in the article "Measurement of the Glial Fibrillary Acidic Protein and Its Breakdown Products GFAP-BDP Biomarker for the Detection of Traumatic Brain Injury Compared to Computed Tomography and Magnetic Resonance ImagingJohn T. Povlishock, PhD, Editor-in-Chief of Journal of Neurotrauma and Professor, Medical College of Virginia Campus of Virginia Commonwealth University, Richmond, notes that "this impressive multi-center study joins with other streams of emerging evidence supporting the use of biomarkers as an important tool in the clinical decision making and prediction process." "Importantly, this study significantly expands upon other studies that speak to the usefulness of GFAP and, specifically, serum-derived GFAP-BDP in identifying those traumatically brain injured patients whose clinical course is complicated by intracranial injury, demonstrating that GFAP-BDP offers good predictive ability, significant discrimination of injury severity, and net benefit in reducing the need for unnecessary scans, all of which have significant implications for the brain injured patient," says Dr. Povlishock. Explore further: Can a biomarker in the blood predict head fracture after traumatic brain injury? More information: The article is available free on the Journal of Neurotrauma (http://online.liebertpub.com/doi/full/10.1089/neu.2014.3635) website until June 18, 2015. Journal reference: Journal of Neurotrauma

Measurement of the Glial Fibrillary Acidic Protein and Its Breakdown Products GFAP-BDP Biomarker for the Detection of Traumatic Brain Injury Compared to Computed Tomography and Magnetic Resonance Imaging. J Neurotrauma. 2015 Apr 15;32(8):527-33 Glial fibrillary acidic protein and its breakdown products (GFAP-BDP) are brain-specific proteins released into serum as part of the pathophysiological response after traumatic brain injury (TBI). We performed a multi-center trial to validate and characterize the use of GFAP-BDP levels in the diagnosis of intracranial injury in a broad population of patients with a positive clinical screen for head injury. This multi-center, prospective, cohort study included patients 16-93 years of age presenting to three level 1 trauma centers with suspected TBI (loss of consciousness, post-trauma amnesia, and so on). Serum GFAP-BDP levels were drawn within 24 h and analyzed, in a blinded fashion, using sandwich enzyme-linked immunosorbent assay. The ability of GFAP-BDP to predict intracranial injury on admission computed tomography (CT) as well as delayed magnetic resonance imaging was analyzed by multiple regression and assessed by the area under the receiver operating characteristic curve (AUC). Utility of GFAP-BDP to predict injury and reduce unnecessary CT scans was assessed utilizing decision curve analysis. A total of 215 patients were included, of which 83% suffered mild TBI, 4% moderate, and 12% severe; mean age was 42.1±18 years. Evidence of intracranial injury was present in 51% of the sample (median Rotterdam Score, 2; interquartile range, 2). GFAP-BDP demonstrated very good predictive ability (AUC=0.87) and demonstrated significant discrimination of injury severity (odds ratio, 1.45; 95% confidence interval, 1.29-1.64). Use of GFAP-BDP yielded a net benefit above clinical screening alone and a net reduction in unnecessary scans by 12-30%. Used in conjunction with other clinical information, rapid measurement of GFAP-BDP is useful in establishing or excluding the diagnosis of radiographically apparent intracranial injury throughout the spectrum of TBI. As an adjunct to current screening practices, GFAP-BDP may help avoid unnecessary CT scans without sacrificing sensitivity (Registry: ClinicalTrials.gov Identifier: NCT01565551).