Whole-blood point-of-care glial fibrillary acidic protein and ubiquitin C-terminal hydrolase L1 biomarkers after traumatic brain injury in the US: a prospective diagnostic prediction of intracranial injury on head CT.

BACKGROUND

Biomarkers like glial fibrillary acidic protein (GFAP) and ubiquitin carboxy-terminal hydrolase L1 (UCH-L1) are being globally recommended as a valuable component in the evaluation of acute TBI. Having a regulatory-approved whole-blood test is imperative to provide consistent and democratized approach to healthcare. This prospective, national multicenter cohort trial (NCT04171960) evaluated the performance of a whole-blood, point-of-care (POC) GFAP/UCH-L1 panel in determining need for head computed tomography (CT) in adult patients presenting to the emergency department (ED) with suspected traumatic brain injury (TBI).

METHODS

Adults presenting to the ED with suspected TBI, Glasgow Coma Scale score 13-15, completed head CT scan, and blood collected within 24 h of injury were included. GFAP and UCH-L1 measured in whole-blood through a POC TBI biomarker test were analyzed using prespecified cutoffs and combined into a single test result and compared with CT findings.

FINDINGS: 970 enrolled participants [mean age 46.8 (18-97); 36%female; 69%White, 18%Black; 19%Hispanic/Latino] were analyzed. 683 participants (70.4%) had 'elevated' and 287 (29.6%) had 'not elevated' TBI blood test result. For detection of CT intracranial injury, the whole-blood TBI test had sensitivity of 96.5% (95%CI 93.6-98.1%) and NPV 96.5% (95%CI 93.7-98.1%).

INTERPRETATION: The GFAP/UCH-L1 whole-blood test had high sensitivity and NPV for prediction of intracranial injury within 24 h of TBI. The platform received U.S.-FDA clearance and expands clinical use of the TBI test beyond the laboratory. This test provides results in 15 min; supporting rapid triage and decision-making in suspected TBI.

FUNDING: Defense Health Agency (DHA) under Contract No. W81XWH19C0071.