Cerebrospinal fluid viral load and biomarkers of neuronal and glial cells in Ramsay Hunt syndrome

Reactivation of varicella zoster virus (VZV) can manifest with facial palsy diagnosed as Ramsay Hunt Syndrome (RHS) or Ramsay Hunt Syndrome zoster sine herpete (RHS‐ZSH). These syndromes are associated with poor prognosis despite treatment with antivirals and corticosteroids. Concentrations of biomarkers such as neurofilament protein (NFL), S‐100β protein and glial fibrillary acidic protein (GFAp) have previously been measured in cerebrospinal fluid (CSF) to assess neuronal damage and glial pathology. We employed immunochemical methods to measure concentrations of NFL, S‐100β protein and GFAp in CSF from patients with RHS (n = 15) and RHS‐ZSH (n = 13) diagnosed by detection of VZV DNA in the CSF by quantitative PCR, and compared with a control group (n = 52). The biomarker concentrations were correlated with CSF viral load and outcome measured by House‐Brackmann score. NFL and GFAp concentrations were increased compared with controls (P = 0.008 and P = 0.04), while S‐100β levels were decreased. This pattern was more pronounced in patients with RHS compared to the patients with RHS‐ZSH (NS and P = 0.028). The amount of viral DNA in CSF correlated with increased GFAp (P = 0.003) and NFL (P = 0.006). No correlations were found between biomarker concentrations and patient outcome. Patients with facial palsy caused by VZV had biochemical signs of neuronal damage and astrogliosis. High amounts of viral DNA may be associated with the degree of damage on neuronal and astroglial cells. Prospective studies are warranted to elucidate the association of elevated biomarkers in the CSF and outcome assessed by more sensitive tests.