Slight and short-lasting increase of serum S-100B protein in extra-cranial trauma

Objective: Serum S-100B protein is an established biochemical marker of traumatic brain injury. At the same time, the question of extra-cranial S-100B release has been raised. This study evaluates the post-traumatic and post-operative release kinetics of S-100B in 45 trauma victims without head injury. Method: Serum S-100B protein was measured on admission and every 24 hours for 4 consecutive days. Results: Initial S-100B was slightly increased (median: 0.54 mu g L-1) and correlated with the severity of extra-cranial trauma (p=0.0004, Mann-Whitney test). Both severely (abdominal or chest trauma with or without bone fractures) and mildly (long bone fractures) injured showed a rapid decline of S-100B (< 0.2 mu g L-1) around 72 hours post-trauma. Extra-cranial surgery caused a secondary increase of S-100B, especially in the mildly injured group (p=0.004, Wilcoxon signed rank test). Conclusions: Extra-cranial injury results in a mild elevation of serum S-100B protein that declines rapidly (1-3 days after injury).