Varicella zoster virus antigens in the epidermis of patients with herpes zoster before and after treatment with acyclovir: an immunohistochemical study.

Using a monoclonal antibody to varicella zoster virus (VZV), an immunohistochemical study was performed before and after treatment with acyclovir (750 mg/day intravenously for 5 - 7 days) to investigate the distribution of VZV antigens in the epidermis of four in-patients with herpes zoster, and to correlate their presence with clinical manifestations of the disease. Biopsy specimens were obtained from epidermal lesions on admission to hospital prior to acyclovir administration, and again following treatment. In all cases, VZV antigens were found extensively in the erythematous and vesicular lesions before treatment, but they were not detected 5 - 7 days later in the ulcerative, crusted or pigmented lesions after acyclovir therapy. Further controlled studies will be necessary to compare the distribution of epidermal VZV antigens in acyclovir-treated patients with that in a placebo group to determine whether the loss of VZV antigens was due to acyclovir or to a natural decrease over time.