Abstract
Disseminated herpes zoster (DHZ), caused by the reactivation of latent varicella-zoster virus (VZV), is usually a condition that affects the immunocompromised population. It is uncommon in a vaccinated population. A previously well, independent 91-year-old lady with no known immunosuppressing conditions presented to the hospital with a productive cough and new confusion. Several days into her admission, she developed a cutaneous maculopapular rash, and then symptoms of headache and seizures, followed by a coma. This coincided with the development of extensive neuroimaging findings, including widespread vasogenic edema and mass effect. Despite treatment with intravenous antiviral therapy, she deteriorated and passed away, with a retrospective diagnosis of DHZ. This case illustrates rapid progression of VZV infection and potential for fatality in elderly, unvaccinated but immunocompetent individuals. It provides a reminder of the importance of maintaining a degree of clinical suspicion for the diagnosis of DHZ in those with suggestive features, especially in unvaccinated individuals.