Continuous varicella-zoster infection associated with acyclovir resistance in a child with AIDS

Acyclovir has become the treatment of choice for varicella-zoster virus (VZV) infections in immunocompromised individuals. This article describes a 4-year-old girl congenitally infected with human immunodeficiency virus who developed a continuous cutaneous infection with VZV that persisted over a 14-month period until her death. Initial episodes of varicella and zoster were responsive to acyclovir treatment; however, subsequent recurrences necessitated administration of multiple courses of acyclovir. Lesions became markedly hyperkeratotic, slow healing, and persistent despite acyclovir therapy. Numerous attempts to isolate virus from the lesions yielded only one isolate late in the course of therapy. This virus clearly demonstrated acyclovir resistance in vitro. Bizarre manifestations of VZV infection could present both diagnostic and therapeutic dilemmas. Prolonged acyclovir treatment of highly immunocompromised patients with acquired immunodeficiency syndrome and severe VZV may lead to the appearance of resistant virus.