Varicella zoster virus infections in the pediatric stem cell transplant patient

Varicella zoster virus (VZV), a member of the human herpesvirus family, cau ses the clinical syndromes of chickenpox during primary infection and shing les on later reactivation. In immunocompromised patients, including those u ndergoing hematopoietic stem cell transplantation, VZV can produce life-thr eatening infections. The most serious forms of VZV infection involve hemato genous dissemination of the virus to vital organs, such as the lung, brain, and liver. Advances in immunoprophylaxis, antiviral chemotherapy, and vacc ine development have provided effective tools to limit the morbidity and mo rtality previously associated with VZV infection in hematopoietic stem cell transplant patients. In this review, we discuss virologic aspects of VZV, pathogenesis of VZV infection, methods of viral diagnosis, clinical manifes tations of infection in both normal and immunocompromised patients, and ava ilable preventative and therapeutic measures.