This pilot study is to assess whether using CytoGam® in combination with ganciclovir is more effective in reducing the CMV viral load over time, as compared to standard treatment with IV ganciclovir only. Serial blood samples are drawn to measure the amount of CMV viral load weekly, while the subject is receiving treatment with ganciclovir, or ganciclovir + CytoGam®. Additional CMV viral load blood sampling (CMV DNA capture qualitative testing only) will occur weekly thereafter until the subject is 8 weeks from the time of CMV diagnosis or until the CMV infection is no longer detectable, whichever is longer duration.