Abstract
The role of low-dose valacyclovir (VCV) in preventing the occurrence of herpes zoster in children after transplantation was evaluated. Low-dose VCV was administered for 17 transplants in 16 patients who underwent transplantation in and after July 2015, and the results compared to that of 24 transplants in 22 patients without herpes zoster prophylaxis in and prior to June 2015. The dose of oral VCV was approximately 10 mg/kg/day once daily, and therapy was continued until the completion of immunosuppressive treatment (administration period: 11.4±9.9 months). In the non-VCV group, herpes zoster developed in approximately half of the patients with a history of varicella. In the VCV group, herpes zoster did not develop during the treatment with VCV, whereas three patients (17.6%) developed herpes zoster after the completion of VCV therapy. Patients with a history of varicella before transplantation and those not receiving prophylaxis with VCV are considered at risk for post-transplant herpes zoster. Long-term low-dose VCV administration is safe and effective as prophylaxis for herpes zoster, and in patients with a history of varicella, at a minimum, it is desirable to continue prophylactic administration until immunocompetence is restored to some extent.
