Varicella zoster virus infection after allogeneic or autologous hemopoietic stem cell transplantation.

A retrospective study was carried out in 161 patients who underwent allogeneic or autologous hemopoietic stem cell transplants. The aim was to determine the frequency, outcome and risk-factors associated with varicella zoster virus (VZV) infection. Post-transplant VZV infection occurred in 29 patients. The median onset of infection was 6.5 months post-transplant, with 82% of cases occurring within the first year. Localized herpes zoster was seen in 27 patients, one patient had varicella, and one patient had simultaneous presentation of both herpes zoster and varicella. No cutaneous or visceral dissemination was noted in the series. Each patient was treated with intravenous acyclovir. Mild complications with postherpetic neuralgia were reported by three patients. There were no deaths from VZV infection. Two risk factors noted to be associated with VZV infection were the presence of graft-versus-host disease in allogeneic transplants and leukemia as the underlying disease in autologous transplants. The overall incidence of post-transplant VZV infection in the present series was relatively low compared with that of other reports involving either allogeneic or autologous bone marrow transplantation.