Serum S100B level as biomarker of traumatic deaths: correlations with injury patterns and postmortem interval

S100B is a calcium-binding protein primarily found in astrocytes and Schwann cells. Accurate estimation of post-mortem interval is vital for reconstructing death timelines and guiding law enforcement. Similarly, precise determination of cause of death serves both legal and medical purposes, aiding judicial outcomes and informing public health strategies. This study aimed to assess serum S100B levels in trauma-related deaths, focusing on head and extracranial injuries, and their variation with postmortem intervals. Serum samples were collected from eighty subjects, including forty trauma cases with head and extracranial injuries and forty non-traumatic controls. Serum S100B concentrations were measured and statistically compared between trauma-related deaths and non-traumatic controls. S100B levels were also measured across different postmortem intervals (0, 6, 12, 24, 48, and 60 h). The current study showed that there was a significant increase in S100B levels in the study group (trauma-related deaths) compared to the control group, with a p-value < 0.001, and no significant differences between head and extracranial causes of death. There was also a significant elevation in S100B concentrations from 0 to 6 h postmortem (p < 0.001). After 6 h post-mortem, several S100B measurements exceeded the assay's upper reportable limit (4000 ng/L), limiting precise quantification beyond this range. In conclusion, post-mortem serum S100B demonstrates potential as a supplementary tool for early post-mortem interval estimation and differentiating trauma-related deaths, regardless of head injury involvement. However, values beyond 12 h post-mortem exceed assay detection limits, highlighting the need for extended measurement ranges in forensic applications.