Varicella-zoster virus infection in children with hematopoietic stem cell transplants

Twenty-one (22%) of 95 children who underwent hematopoietic stem cell transplantation developed varicella-zoster virus (VZV) infection. Patients were followed for a median of 400 days (range: 41 to 1359). The Kaplan-Meier estimated probability for developing VZV infection at 2 years post-transplant was 47%. Seventeen patients developed tester infection (ZI) at a median of 102 days from conditioning regimen (range, 0 to 306 days). Zoster infection occurred later in patients who received ganciclovir posttransplant. Patients were treated with acyclovir (15 patients) or famciclovir (2 patients). Treatment was administered intravenously in 10 patients and by mouth in 7 patients. Six patients were treated exclusively on an outpatient basis. Four patients developed chickenpox at a median of 416 days from conditioning regimen (range, 45 to 641 days). Two of these patients were treated with acyclovir on an outpatient basis. No episode of visceral dissemination, superimposed bacterial infection, or VZV-related death was encountered. No risk factors for VZV infection were identified by univariate and multivariate analyses. Based on the efficacy and safety of oral antiviral agents, we suggest that outpatient treatment of uncomplicated VZV infection posttransplant may be feasible.