A Clinical and Laboratory Comparison of Varicella-Zoster Virus (VZV) and Epstein-Barr Virus (EBV): Two Cases of Herpesvirus Meningitis in Immunocompetent Adults and a Literature Review.

Varicella-zoster virus (VZV) and Epstein-Barr virus (EBV) are uncommon causes of aseptic meningitis in immunocompetent individuals. We report two cases of polymerase chain reaction (PCR)-confirmed viral meningitis caused by VZV and EBV in previously healthy young adults and compare their clinical presentation, cerebrospinal fluid (CSF) findings, neuroimaging, treatment response, and outcomes with previously reported cases. Both patients presented with lymphocytic meningitis and normal neuroimaging findings. The patient with VZV meningitis experienced rapid clinical improvement following acyclovir therapy and developed a vesicular rash two days after symptom onset, whereas the patient with EBV meningitis presented with a broader range of systemic and neurological symptoms and showed a more gradual recovery. Despite a shared lymphocytic CSF pattern, the two cases demonstrated distinct clinical and laboratory profiles. These findings highlight the importance of molecular testing for definitive diagnosis and support consideration of both viruses in the differential diagnosis of aseptic meningitis in immunocompetent patients.