S-100 serum levels and outcome after severe head injury

S-100B a protein of astroglial cells is described as a marker for neuronal damage. Reliable outcome prediction from severe head injury is still unresolved. Clinical scores like the Glasgow Coma Score (GCS) and diagnostic scores like the Marshall CT Classification (MCTC) are well established and investigated, but there are still some concerns about these tools. The aim of this study was to investigate the predictive value of the initial serum level of S-100B. 44 patients with severe head injury (GCS < 9) were included. Blood samples were drawn within 1 to 6 hours of injury. After a period of 11 months their outcome was correlated using the Glasgow Outcome Scale. Patients with good outcome had significantly lower serum concentrations of S-100 on admission (0.96 microgram/l versus 5.5 micrograms/l mean, p < 0.0001). In addition patients with a S-100 serum level below 2 micrograms/l showed a significant better rating on the GOS at follow-up (4 points versus 1.8 points mean, p < 0.0001). With this cut-off line it was possible to predict longterm outcome with a sensitivity of 75% and specitivity of 82%. The serum level of S-100B calculated with one to six hours of a severe head injury is a useful additional outcome predictor.