Detection of viral DNA in the endolymphatic sac in Ménière's disease by in situ hybridization.

The main purpose of this study is to search for a viral etiology in Ménière's disease by examining the presence or absence of herpes family virus DNA in the endolymphatic sac (ES) using the in situ hybridization method. This was a prospective study with the ES from 10 patients with Ménière's disease and from 7 control cases without any pre-mortem ear diseases except a case of acoustic tumor. These 10 patients underwent the ES surgery. The presence of herpes family virus DNA, such as herpes simplex virus types 1 and 2 (HSV1&2), varicella-zoster virus (VZV), Epstein-Barr virus (EBV) and human cytomegalovirus (CMV), was examined using the in situ hybridization method. Serum antibody titers against these viruses just before the ES surgery were studied in these patients. Of the 10 specimens from the patients with Ménière's disease, 7 were positive for VZV, 4 for EBV, 1 for CMV and none for HSV1&2, although the serum antibody titers against these viruses did not show any significant elevation in these patients just before the ES surgery. This result suggests that the viral DNA in the ES is inactive and is present in a latent form. From the statistical analysis, it can be postulated that VZV infection in early childhood may reach the ES and play a role in the pathogenesis of Ménière's disease (p = 0.0235). The double infection with both VZV and EBV tended to be another candidate for the pathogenesis of Ménière's disease (p = 0.0557).