Expression and distribution of β amyloid precursor protein immunomarkers in the detection of diffuse axonal injury

Introduction/Objective. The diffuse axonal injury has a very important place in clinical and forensic aspects of neurotraumatology. A special challenge is proving it in situations of short survival (less than two hours) after a craniocerebral injury. The aim of this study was to determine the efficacy of beta-amyloid precursor protein (?APP) immunohistochemical staining in postmortem diagnosis of axonal injuries in head injury survival shorter than two hours, its expression and distribution through the brain tissue of the deceased. Methods. 36 adult fatalities, both sexes, injured by acceleration-deceleration mechanisms were divided into two groups: died up to two hours and died more than two hours after the injury. Immunostaining of brain tissue samples (frontal parasagittal white mass, genu and splenium of the corpus callosum and rostral pons) was used to register ?APP positivity. Data were processed by methods of descriptive and inferential nonparametric statistics, and p < 0.05 was considered statistically significant. Results. The ?APP immunopositivity was shown in 88.9% of cases (82.3% of ? two hours group vs. 94.7% of > two hours group). ?APP expression was enhanced towards the posterior structures of the brain. The shortest survival period with detected ?APP immunopositivity was 20-25 minutes, in three cases. There was an association of ?APP expression in the brainstem and interhemispheric/paramesencephalic subarachnoid hemorrhage (p = 0.035). Conclusion. ?APP immunohistochemical staining is effective in proving diffuse axonal injury in casualties that survived less than half an hour. Interhemispheric/paramesencephalic subarachnoid hemorrhage may indicate a more severe form of axonal injury.