Blood Test Helps Determine Traumatic Brain Injury Severity

A new blood test could help emergency room doctors quickly diagnose traumatic brain injury and determine its severity and the test could help identify patients who might benefit from extra therapy or novel treatments.

Brain derived neurotrophic factor (BDNF) is important for neuronal survival and regeneration the diagnostic and prognostic values of serum BDNF in traumatic brain injury (TBI) and its association with two other proteins has been investigated.


A large group of collaborating scientists led by those at Johns Hopkins University School of Medicine (Baltimore, MD, USA) examined serum BDNF in two independent cohorts of TBI cases presenting to the emergency departments. At Johns Hopkins Hospital, 76 patients were studied and at San Francisco General Hospital (CA, USA), 80 patient were included in the study and a control group of 150 patients without TBI were enrolled.

The teams investigated the association between BDNF, Glial fibrillary acidic protein (GFAP) and Ubiquitin C-terminal hydrolase -L1 (UCH-L1) and recovery from TBI at six months in a pilot cohort. The investigators found that the levels of BDNF, taken within 24 hours of someone's head injury, could predict the severity of a TBI and how a patient would fare. While healthy people averaged 60 ng/mL of BDNF in their bloodstreams, patients with brain injuries had less than one-third of that amount, averaging less than 20 ng/mL, and those with the most severe TBIs had even lower levels, around 4 ng/mL. Moreover, patients with high levels of BDNF had mostly recovered from their injuries six months later, but in patients with the lowest levels of BDNF, symptoms still lingered at follow-up. The results suggest that a test for BDNF levels, administered in the emergency room, could help stratify patients.

Frederick Korley, MD, PhD, an assistant professor of emergency medicine and first author of the study said, “Compared to other proteins that have been measured in traumatic brain injury, BDNF does a much better job of predicting outcomes. The advantage of being able to predict prognosis early on is that you can advise patients on what to do, recommend whether they need to take time off work or school, and decide whether they need to follow up with a rehab doctor or neurologist.” The study was published on July 10, 2015, in the Journal of Neurotrauma.

Related Links:
Johns Hopkins University School of Medicine 
San Francisco General Hospital