Varicella-Zoster Disease of the Central Nervous System in Immunocompetent Children: Case Series and a Scoping Review

Background: Varicella-Zoster Virus (VZV) is characterized by its ability to enter a dormant state within the body. When the wild or vaccine virus reactivates, it can lead to herpes zoster (HZ), which infrequently manifests as a neuroinfection. Objectives: The aim of the study was to analyze the clinical manifestations and outcomes associated with VZV reactivation in the CNS in immunocompetent children. Methods: We searched medical databases for case reports using the keywords "zoster", "meningitis", "encephalitis", and "immunocompetent". The inclusion criteria were age below 18 years, any gender, race, and ethnicity, no features or history of immunodeficiency, and confirmation of VZV reactivation through the detection of VZV DNA in the CSF. Patients were categorized into two groups: children experiencing the reactivation of the wild virus and children with the vaccine strain virus. Results: The cohort included six children hospitalized in our hospital and 49 children reported in the literature. In 37 (67%), a wild-type virus was detected, while in 18 (33%), an infection was caused by the vaccine strain. There were no differences in the clinical presentation between the two groups. A typical rash was observed in 32 (58%) children. Approximately 41 of the 55 children (75%) received antiviral treatment. Four patients experienced complications. Conclusions: Neither a history of VZV immunization nor the absence of a skin rash can definitively exclude VZV meningitis. It is important to note that any seemingly healthy child, regardless of recognized risk factors, could develop HZ meningitis.