Objective: Patients presenting in the emergency department with a mild injury to the head pose a particular challenge due to their high prevalence but low rate of traumatic brain injury. However, missed traumatic brain injuries may result in fatal consequences. Therefore we investigated the diagnostic performance of serological protein S100B measurement in adult patients presenting with mild head injury and a GCS 13-15 to identify traumatic brain injury.
Design and methods: We conducted a systematic review of the literature. Two reviewers screened potential studies for inclusion and independently extracted study data. For all included studies, we applied the QUADAS quality assessment tool for systematic reviews of diagnostic accuracy and abstracted the raw data for every included study. Included studies presented results either in 2x2 contingency tables or provided data allowing their construction.
Results: Of 76 studies identified, 8 met the inclusion criteria. Methodology quality was moderate and all studies fulfilled at least 50% of the QUADAS criteria. Overall, the sensitivity to detect intracranial lesions was 94% (95% CI 88-98%) and specificity was 44% (95% CI 30-58%). The subgroup analysis showed significant differences only between studies with different S100B cutoff values (0.10 μg/l versus >0.10 μg/l). The combined odds ratio was 10.3 (95 CI 4.2-24.9).
Conclusions: Serological protein S100B measurement may be helpful as a screening test to identify patients with higher risk of traumatic brain injury for further diagnostic assessment.