Effectiveness of valacyclovir prophylaxis against the occurrence of cytomegalovirus infection in kidney transplant recipients

Background : Cytomegalovirus (CMV) infection is a crucial infection in kidney transplant recipients (KTRs) despite advancements in diagnostic and treatment methods. There are still many controversies about the ways to prevent CMV infection. Methods : We retrospectively analyzed 153 KTRs who underwent kidney transplantation (KT) between September 2013 and January 2016. We classified KTRs into two groups: valacyclovir prophylaxis group (intravenous ganciclovir for 2 weeks after KT, followed by oral valacyclovir for 3 months) and historical control group (only intravenous ganciclovir for 2 weeks after KT). We evaluated the incidence of CMV infection, clinical outcomes, CMV-free survival rate between the two groups and risk factors for the development of CMV infection. Results : Mean time between KT and diagnosis of CMV infection was 4.5±3.3 months. The valacyclovir prophylaxis group showed lower incidence of CMV infection than the historical control group (21.7% vs. 43.9%, P=0.011). The valacyclovir prophylaxis group showed higher CMV-free survival rate than the control group (P=0.011). In multivariable- adjusted analysis, independent risk factors for the development of CMV infection were no valacyclovir prophylaxis, older age at KT, thymoglobulin induction, and delayed graft function. Conclusions: Valacyclovir prophylaxis for 3 months showed significant reduction in the incidence of CMV infection in KTRs. Therefore, we suggest valacyclovir prophylaxis for 3 months in KTRs with risk factors such as old age, thymoglobulin induction, and delayed graft function.