The objective for this retrospective clinical study is to describe the incidence of CMV infection in orthoptic liver transplant recipients who receive oral valganciclovir or ganciclovir as their CMV prophylactic anti-viral therapy.~Endpoints:~Primary Endpoint~CMV infection will be characterized as viremia, syndrome or disease by the abovementioned methods for up to one year post-transplantation.~Secondary Endpoints~Patient and allograft survival based on donor/recipient CMV status~Incidence of graft rejection and loss associated with CMV infection~Time to hepatitis C virus (HCV) occurrence~Incidence of HSV, EBV and VZV reactivations~Severity of HCV occurrence based on biopsy reports based on the Knodell score~Safety and tolerability of oral valganciclovir and ganciclovir
Null Hypothesis:~There is no significant difference in the incidence of CMV infection when using oral valganciclovir or ganciclovir as prophylactic anti-viral therapy.~Alternate Hypothesis:~There exists a significant difference in the incidence of CMV infection when oral valganciclovir is used for CMV prophylaxis rather than oral ganciclovir. A formal hypothesis to be tested should be defined.