Varicella zoster encephalitis in an immunocompetent patient.

Encephalitis is inflammation of the brain parenchyma, most often caused by viruses. Historically, data have shown herpes simplex virus 1 and 2 to be the most common causes of viral encephalitis, with cases due to varicella zoster virus (VZV) more often seen in older age and immunocompromised states. However, emerging data show VZV as an increasingly common culprit of encephalitis in young, immunocompetent patients. PCR analysis of the cerebrospinal fluid is the most accurate diagnostic modality for viral encephalitis. Appropriate and complete treatment hinges on accurate identification of the cause of encephalitis, underscoring the need for comprehensive testing. We present a case of VZV encephalitis in an immunocompetent male patient in his 40s.