Serum S100 Protein as a Predictor of Long Term Outcome in Mild and Moderate Traumatic Brain Injury

Background: S-100B protein is a promising marker of injury severity and outcome after head injury. Objective: The aim of this study was to consider the diagnostic and prognostic validity of the initial serum levels of S-100B in clinical use. Patients and Methods: Thirty patients with mild and moderated traumatic brain injury were included in this prospective study between June 2010 and June 2011. Neurologic examination and CT-scan were performed to all patients. Serum S-100B levels were measured by immunoluminometric technique at six hours, 24 hours, and at the third, fifth, and seventh day. Results: The results showed a significant difference between the S-100B serum concentration in mild and moderate head injuries. A statistically significant correlation was observed between an increase of S-100B and a cerebral pathological finding in CT scans. The study found S-100B cut-off level of >0.32ptg/1 for prediction of unfavorable outcome. The specificity and sensitivity of S-100B were 0.85 and 0.20 respectively. Conclusion: Serum S-100B protein reflects injury severity and improves prediction of long term outcome after mild and moderate TBI traumatic brain injury.