Detection of Varicella-Zoster Virus DNA in Tear Fluid and Saliva of Patients with Ramsay Hunt Syndrome

Abstract

Ramsay Hunt syndrome develops when the varicella-zoster virus (VZV) is reactivated. In the present study, we examined the secretion kinetics of VZV DNA in the tear fluid, submandibular gland saliva and parotid gland saliva of 15 patients with Ramsay Hunt syndrome. The presence of VZV DNA was detected using PCR and a microplate hybridization method. Hybridization signals were measured using the fluorescence density of an enzymatic reaction product using fluoroscan and a system involving streptavidin-conjugated β-galactosidase. The results were converted into numerical values and used to estimate the number of virus DNA copies.
VZV DNA was detected in the tear fluid, submandibular gland saliva and parotid gland saliva of the Ramsay Hunt syndrome patients. The rate of VZV DNA detecton in the submandibular gland saliva was 72%, and the detection rate in the parotid gland saliva was 57%. The detection rate in the tear fluid was 27%, which is significantly lower than the other two detection rates. Regarding the submandibular gland saliva and the parotidgland saliva, the VZV DNA was detected in samples collected at a comparatively early stage of onset. In the tear fluid, the detection rate increased significantly in samples collected 2 weeks after onset or later. Thus, differences in the detection rate were observed depending on the type of secretory gland and the timing of the sample collection. The VZV DNA in the tear fluid is thought to derive from the ganglion trigeminale. The increase and decrease in the number of VZV DNA copies detected in samples collected at different times is considered to substantiate VZV reactivation in Ramsay Hunt syndrome.