It was shown that everolimus suppresses the DNA synthesis of the virus, prevents the spread of CMV infection, and CMV-specific CD8+/CD4+ T cell response increases in transplant patients treated with everolimus.2,4 However, a case of everolimus-related CMV colitis has been previously reported in a patient with metastatic breast cancer.5 In the reported case, severe CMV colitis occurred in the third month of everolimus treatment and relapsed when everolimus was restarted after antiviral therapy. This evidence concerns the gene CD4 and cytomegalovirus infection.