Protein S-100B as a serum marker of brain damage in severe head injury: preliminary results

The objective of our study was to investigate S-100B protein as a serum marker of brain cell damage after severe head injury. Eighty-three patients with severe head injury (Glasgow Coma Scale < or =8) were included in this prospective study. Venous blood samples for S-100B protein were taken after admission and every 24 h for a maximum of 10 consecutive days. Outcome was assessed at 6 months using the Glasgow Outcome Scale. In this study, we analysed the preliminary results from the outcomes of 25 patients at 6 months. Levels of S-100B were significantly higher in patients with unfavourable outcome compared to those with favourable outcome. In patients with favourable outcome, slightly increased initial levels of S-100B returned to normal within 3 to 4 days. In patients with unfavourable outcome, initial levels were markedly increased, with a tendency to decrease from day 1 to day 6. After day 6, there was a secondary increase in serum S-100B, indicating secondary brain cell damage. Our preliminary results suggest that serum S-100B protein might be a promising biochemical marker which may provide additional information on the extent of primary injury to the brain and the prediction of outcome after severe head injury.