Reliability of Post-mortem Biochemical Investigations after FatalTraumatic Brain Injury

Objective: The aim was to test the reliability of former reported results of post-mortem laboratory investigations using cerebrospinal fluid (CSF) and serum levels of the biomarkers S100B and neuron specific enolase (NSE) to further evaluate the brain damage after fatal traumatic brain injuries. Methods: CSF and serum samples of 92 cases were collected during routine autopsies. The cases were divided into four groups regarding the causes of death in traumatic brain injury (TBI), isolated torso trauma, diffuse cerebral hypoxia and acute myocardial infarction. The samples were analysed using chemiluminescent immunoassays and the haemolytic index was quantified as internal control per sample (Roche Diagnostics). Results: There were significant differences in CSF values between TBI and all control cases (p<0.001), especially in comparison to fatal non-head injuries (p<0.05). Biochemical approaches in post-mortem serum are not suitable for both proteins. The marker levels increased with longer TBI survival time and peaked within the first three days after trauma. Former mentioned CSF cut-off values could be confirmed. Conclusion: Post-mortem investigations of CSF S100B and NSE can be declared a valuable tool in forensic practice since their levels indicate fatal TBI when empirically determined critical CSF values are reached.