Human herpes virus 6B and mesial temporal lobe epilepsy with hippocampal sclerosis (MTLE-HS): is there a link?

摘要

Purpose: Human Herpesvirus 6 (HHV-6) is a ubiquitous virus acquiredmainly during the first 2 years of life. Mesial Temporal Lobe Epilepsywith Hippocampal Sclerosis (MTLE-HS) is the most frequent pharmacoresistantepilepsy. One of the most common antecedents of MTLE-HS isfebrile seizures (FS). Although the aetiology of MTLE-HS remainsunclear, evidences suggest that HHV-6 infection could be implicated.The objective of this study was to investigate the presence of HHV-6BDNA in the hippocampus and adjoining temporal cortex of MTLE-HSpatients submitted to surgery.Methods: A total of 22 MTLE-HS (13 females and nine males) caseswere studied. The mean age at surgery was 39 9 years and mean ageat onset of seizures was 10 6 years. These study cohort was comparedto a group of 10 epileptic patients without MTLE-HS (six females, fourmales; mean age = 26 15 years) and with autopsy material from nineindividuals without neurological disease. HHV-6B DNA was identifiedby real-time PCR with specific TaqMan probes.Results: We detected HHV-6B DNA in only one hippocampus from aMTLE-HS patient. This patient had a disease duration of 36 years and ahistory of febrile seizures in childhood. None of the non-MTLE or controlsspecimens showed positivity for HHV-6B.Conclusions: Our findings do not support a relevant etiologic role forHHV-6B in MTLE-HS, at least in this population. However, the possiblerole of viral infection in MTLE-HS epileptogenic process, in individualcases, cannot be excluded.