The Role of Varicella Zoster Virus (VZV) in Central Nervous System Infectious Syndromes.

We describe the proportion of VZV infection in central nervous system (CNS) infectious syndromes in a single Israeli medical center. An observational cohort study was conducted in Kaplan Medical Center (a secondary hospital, Israel) between July 1, 2014, and March 31, 2019. Included were adult patients (≥ 16 years old) with CNS infection with an aseptic CSF profile that were subjected to molecular tests for herpes viruses, HSV either 1 or 2, VZV, enteroviruses, and IgM for West Nile virus (WNV). Clinical presentation suggestive of CNS infection led to lumbar puncture and CSF analysis in 1500 patients yielding 178 cases with aseptic CSF profile. For 62/109 (55.9%) cases of meningitis, the etiology remained unknown, enterovirus accounted for 21 cases (18.9%), VZV for 16 (14.4%), and HSV 1 for 7 (6.3%). One case each of bacterial, fungal, and parainfluenza virus accounted for the other 3 cases. For 30/63 (47.6%) cases of encephalitis, the etiology remained unknown, HSV accounted for 11 cases (17.5%), VZV for 8 (12.7%), and WNV for 10 (15.9%); in two cases, enterovirus was identified and one case of influenza A and one of mycoplasma, accounted for the rest. In six patients with myelitis VZV was identified in 4 (66.7%). Notably, a typical herpetic rash was identified in only 11/28 (39.28%) of cases of VZV CNS infection. VZV is a significant cause of viral CNS infections. In the majority of patients with neurologic syndrome and evident VZV there is no association with a typical herpetic rash. These results apply to Israeli population and likely to other populations with similar background of VZV past infections.