Study: Blood test is 94 percent reliable in detecting concussions in kids, confirmed by CT scans.
Researchers at Orlando Health have developed a blood test that can detect even the most subtle signs of a concussion in children, correctly identifying the presence of traumatic brain injuries 94 percent of the time in a recent study.
“This could ultimately change the way we diagnose concussions, not only in children, but in anyone who sustains a head injury,” said Linda Papa, MD, MSC, an emergency medicine physician and NIH funded researcher at Orlando Health and lead author of the study. “We have so many diagnostic blood tests for different parts of the body, like the heart, liver and kidneys, but there’s never been a reliable blood test to identify trauma in the brain. We think this test could change that,” she said.
In a new study published in the journal Academic Emergency Medicine, Papa and her team recently performed CT scans on 152 children and compared the results of those scans with results from the blood test she developed. As expected, the high definition imagery from the CT scans was able to identify which patients had suffered visible traumatic brain injuries. Moreover, the study showed that the blood test detected symptoms of concussions, even when brain injuries were not visible on the CT scan.
The team then tested blood serum from the same patients, which was taken less than 6 hours after their injuries. “With our blood test, we were able to identify the presence of brain injuries 94 percent of the time,” said Papa. “This simple blood test was nearly as accurate as a state-of-the-art CT scan.”
Even more impressive, the blood test also gave doctors an indication of how severe the brain injury was. “We were looking at different types of brain lesions detected by the CT scans, ranging from mild to serious injuries, and found that the biomarker we tested for actually corresponded to the injuries. Levels of the biomarker were lower in mild cases, and were much more elevated in severe case,” said Papa.
The biomarker this particular blood test looks for is known as glial fibrillary acidic protein (GFAP). These proteins are found in glial cells, which surround neurons in the brain.
When there’s an injury to the brain cells, the GFAP are released. What makes them unique is that they pass the blood-brain barrier and enter the bloodstream, which makes them easy to detect with this particular test.
Currently, almost all concussions in children are diagnosed only by symptoms, which are either observed, like vomiting or balance problems, or symptoms that are reported by the child, like headaches, blurred vision or feeling groggy. Neither scenario gives doctors an objective indication of the severity of the injury.
CT scans can provide a more definitive profile of the injury, “however, they are expensive and are associated with radiation exposure,” said Papa. “You really want to minimize the amount of CTs you do to your patients, especially children, who are a lot more sensitive to radiation and the side effects that can come with it.”
“If there was a simple diagnostic tool like a blood test that can tell us quickly and accurately if a brain injury has occurred, and how severe it might be, that would be ideal,” said Papa. “That’s what we are striving for with this project.”
In fact, Papa envisions the development of mobile devices that could diagnose concussions on the spot, much like the devices diabetics use to test their blood with a simple finger prick and a drop of blood.
“The idea is to get a point-of-care test that could be used on the field, to help the coaches, the trainers and the athletic directors, make a decision then and there about whether the child should go back to play,” said Papa.
It’s estimated nearly a quarter of a million children a year are treated in hospitals for traumatic brain injuries like concussions, that occur while playing sports. That’s an average of nearly 700 children a every day.
“If we could find a simple test that takes the guess work out of diagnosing these kids, that would completely change the way we approach concussions and would certainly give parents greater peace of mind,” said Papa.
Researchers plan to do more studies with the blood test, but they hope it will be commercially available within the next 5 years.
Source: Shannon McCormick – Orlando Health
Image Source: The image is credited to Orlando Health
Video Source: The video is available from the Orlando Health YouTube page
Original Research: Abstract for “Performance of Glial Fibrillary Acidic Protein in Detecting Traumatic Intracranial Lesions on Computed Tomography in Children and Youth With Mild Head Trauma” by Linda Papa, Mark R. Zonfrillo, Jose Ramirez, Salvatore Silvestri, Philip Giordano, Carolina F. Braga, Ciara N. Tan, Neema J. Ameli, Marco Lopez and Manoj K. Mittal in Academic Emergency Medicine. Published online November 9 2015 doi:10.1111/acem.12795
Abstract
Performance of Glial Fibrillary Acidic Protein in Detecting Traumatic Intracranial Lesions on Computed Tomography in Children and Youth With Mild Head Trauma
Objectives
This study examined the performance of serum glial fibrillary acidic protein (GFAP) in detecting traumatic intracranial lesions on computed tomography (CT) scan in children and youth with mild and moderate traumatic brain injury (TBI) and assessed its performance in trauma control patients without head trauma.
Methods
This prospective cohort study enrolled children and youth presenting to three Level I trauma centers following blunt head trauma with Glasgow Coma Scale (GCS) scores of 9 to 15, as well as trauma control patients with GCS scores of 15 who did not have blunt head trauma. The primary outcome measure was the presence of intracranial lesions on initial CT scan. Blood samples were obtained in all patients within 6 hours of injury and measured by enzyme-linked immunosorbent assay for GFAP (ng/mL).
Results
A total of 257 children and youth were enrolled in the study and had serum samples drawn within 6 hours of injury for analysis: 197 had blunt head trauma and 60 were trauma controls. CT scan of the head was performed in 152 patients and traumatic intracranial lesions on CT scan were evident in 18 (11%), all of whom had GCS scores of 13 to 15. When serum levels of GFAP were compared in children and youth with traumatic intracranial lesions on CT scan to those without CT lesions, median GFAP levels were significantly higher in those with intracranial lesions (1.01, interquartile range [IQR] = 0.59 to 1.48) than those without lesions (0.18, IQR = 0.06 to 0.47). The area under the receiver operating characteristic curve (AUC) for GFAP in detecting children and youth with traumatic intracranial lesions on CT was 0.82 (95% confidence interval [CI] = 0.71 to 0.93). In those presenting with GCS scores of 15, the AUC for detecting lesions was 0.80 (95% CI = 0.68 to 0.92). Similarly, in children under 5 years old the AUC was 0.83 (95% CI = 0.56 to 1.00). Performance for detecting intracranial lesions at a GFAP cutoff level of 0.15 ng/mL yielded a sensitivity of 94%, a specificity of 47%, and a negative predictive value of 98%.
Conclusions
In children and youth of all ages, GFAP measured within 6 hours of injury was associated with traumatic intracranial lesions on CT and with severity of TBI. Further study is required to validate these findings before clinical application.
“Performance of Glial Fibrillary Acidic Protein in Detecting Traumatic Intracranial Lesions on Computed Tomography in Children and Youth With Mild Head Trauma” by Linda Papa, Mark R. Zonfrillo, Jose Ramirez, Salvatore Silvestri, Philip Giordano, Carolina F. Braga, Ciara N. Tan, Neema J. Ameli, Marco Lopez and Manoj K. Mittal in Academic Emergency Medicine. Published online November 9 2015 doi:10.1111/acem.12795
