Cytomegalovirus Infection according to Cell Source after Hematopoietic Cell Transplantation in Pediatric Patients

PURPOSE: This study was performed in order to evaluate the incidence and characteristics of cytomegalovirus (CMV) infection in children with acute leukemia according to donor source and graft type. MATERIALS AND METHODS: We retrospectively identified children with acute leukemia who had received allogeneic hematopoietic cell transplantation at Samsung Medical Center in Korea from October 1998 to December 2009. RESULTS: In total, 134 recipients were identified. The patients were classified into the following three groups: unrelated cord blood (CB, n=36), related bone marrow or peripheral blood stem cells (RD, n=41), and unrelated bone marrow or peripheral blood stem cells (UD, n=57). The 365-day cumulative incidence of CMV antigenemia was not significantly different among the three groups (CB 67% vs. RD 49% vs. UD 65%, p=0.17). However, CB recipients had the highest median value of peak antigenemia (CB 160/2×10(5) leukocytes vs. RD 7/2×10(5) leukocytes vs. UD 19/2×10(5) leukocytes, p<0.01) and the longest duration of CMV antigenemia than the other stem cell source recipients (CB 87 days vs. RD 17 days vs. UD 28 days, p<0.01). In addition, the 730-day cumulative incidence of CMV disease was the highest in the CB recipients (CB 36% vs. RD 2% vs. UD 5%, p<0.01). Thirteen CB recipients developed CMV disease, in which five of them had more than one organ involvement. Two patients, who were CB recipients, died of CMV pneumonia. CONCLUSION: This study suggests that CB recipients had both longer and higher cumulative incidences of CMV infection. Therefore, a more aggressive and effective strategy of CMV management should be considered in CB recipients.