Neuron-specific enolase, but not S100B or myelin basic protein, increases in peripheral blood corresponding to lesion volume after cortical impact in piglets.

A peripheral indicator of the presence and magnitude of brain injury has been a sought-after tool by clinicians. We measured neuron-specific enolase (NSE), myelin basic protein (MBP), and S100B, prior to and after scaled cortical impact in immature pigs, to determine if these purported markers increase after injury, correlate with the resulting lesion volume, and if these relationships vary with maturation. Scaled cortical impact resulted in increased lesion volume with increasing age. Concentrations of NSE, but not S100B or MBP, increased after injury in all age groups. The high variability of S100B concentrations prior to injury may have precluded detection of an increase due to injury. Total serum markers were estimated, accounting for the allometric growth of blood volume, and resulted in a positive correlation of both NSE and S100B with lesion volume. Even with allometric scaling of blood volume and a uniform mechanism of injury, NSE had only a fair to poor predictive value. In a clinical setting, where the types of injuries are varied, more investigation is required to yield a panel of serum markers that can reliably predict the extent of injury. Allometric scaling may improve estimation of serum marker release in pediatric populations.