Investigation of the role of HSP70 immunohistochemical staining method to the diagnosis of sudden unexpected death in epilepsy in autopsies.

PURPOSE: Epilepsy is a neurological disorder characterized by recurrent seizures, affecting millions of people worldwide. Sudden Unexpected Death in Epilepsy (SUDEP) is the leading cause of mortality among epilepsy patients. Diagnosing SUDEP is particularly challenging in forensic medicine due to the absence of specific findings in autopsies. This study aimed to contribute to the diagnosis of SUDEP by evaluating HSP70 immunohistochemical staining in the hippocampal region.

METHODS

In this study, brain tissue samples from 83 cases with a history of epilepsy and 26 control cases were collected during autopsies. Sections of the hippocampal region were evaluated using HSP70 immunohistochemical staining under light microscopy. Additionally, the sociodemographic characteristics, macroscopic and microscopic autopsy findings, medication usage, comorbidities, and causes of death of the cases were analyzed.

RESULTS

The study revealed that 63.9% of the deaths were attributed to SUDEP. The average age of the SUDEP group was 31.86 ± 12.64 years. No statistically significant association was found between antiepileptic drug usage and SUDEP deaths, although 34% of SUDEP cases lacked evidence of medication use based on clinical and toxicological findings. Immunohistochemical analysis showed significantly higher HSP70 staining in the SUDEP group compared to the non-SUDEP group. Significant staining was observed in granular cells, neuronal cells, and a combination of both.

CONCLUSION

HSP70 staining of the hippocampus demonstrated significantly higher staining across all subtypes in SUDEP cases. The results indicate that HSP70 immunohistochemical staining provides significant support for SUDEP diagnosis and could be employed as an ancillary staining method in forensic medicine practices.