Background: The use of cytomegalovirus (CMV)-"safe" blood has been recommended for CMV seronegative patients with newly diagnosed malignant disease for whom bone marrow transplantation is a future option.
Study design and methods: To evaluate this policy, 76 CMV-seronegative children with lymphoreticular malignancies or solid tumors were randomly assigned to receive either blood components that were not screened for CMV antibody or CMV-seronegative red cell (RBC) and platelet units. Subjects were followed for evidence of CMV infection by the use of enzyme-linked immunosorbent assays and virus isolation. Follow-up continued long after the blood transfusions to determine the risk of community-acquired CMV infection.
Results: No cases of transfusion-acquired CMV infection were documented. The prevalence of CMV IgG and IgM antibody in blood donors was 40.5 and 0.9 percent, respectively. Patients assigned to receive standard blood components and CMV-negative components were given a median (range) of 7 (1-30) and 9 (1-38) RBC units and 11 (0-123) and 14 (0-71) platelet units, respectively. The risk of transfusion-acquired CMV infection is estimated to be less than 1 in 698 donor exposures. Two patients developed asymptomatic community-acquired CMV infection, for an incidence of 1.7 percent per patient-year of follow-up.
Conclusion: The risk of transfusion-acquired CMV infection in this population is low, largely because of the patients' low level of exposure to seropositive blood and the use of relatively white cell-reduced components for purposes other than CMV prevention. Such children at this center therefore continue to receive standard blood components. Strategies to prevent CMV seroconversion in these children should include parental education to minimize the risk of community-acquired infection.