Advances made in the field of hematopoietic stem cell transplantations (HSCT) over the past 20 years may have had an impact on the distribution of posttransplantation infections. We sought to retrospectively analyze the epidemiology and risk factors for bacterial, fungal, and viral infections in children after allogeneic HSCT in a cohort of 759 children who underwent allogeneic HSCT in a single institution between 1990 and 2009. The association between infections and risk factors of interest at 0 to 30 days, 31 to 100 days, and 101 days to 2 years posttransplantation was evaluated using logistic regression. Difference among the subtypes within each category was studied. There were 243 matched-related donors, 239 matched-unrelated donors (MUDs), and 176 haploidentical donor transplantations. Era of transplantation (0–30 days), peripheral blood stem cell product, acute graft-versus-host disease (aGVHD; 31–100 days), and chronic GVHD (cGVHD; 101–730 days) were associated with higher risk for bacterial infections at the respective time periods. Patients with aGVHD (31–100 days), cGVHD, and older age (101–730 days) were at higher risk for fungal infections. Cytomegalovirus (CMV) donor/recipient (D/R) serostatus (0–100 days), era of transplantation, MUD HSCT (31–100 days), and cGVHD (101–730 days), influenced viral infections. Gram-positive outnumbered gramnegative bacterial infections; aspergillosis and candidemia were equally prevalent in all time periods. Haploidentical donor HSCT was not associated with an increased risk of infections. There seems to be a continuum in the timeline of infections posttransplantation, with bacterial, fungal, and viral infections prevalent in all time periods, particularly late after the transplantation, the risk affected by GVHD, CMV, D/R status, product type, older age, and use of unrelated donors.

Summary:The objective of this study is to investigate the outcome of children 24 months of age or younger (infants) at the time of allogeneic bone marrow transplantation (BMT) for acute leukemia or myelodysplasia. We analyzed the survival rate, prognostic factors, incidences of late sequelae, and immune reconstitution in 22 infants who underwent allogeneic BMT. The 5-year event-free survival estimate was 45.5% (95% confidence interval (CI), 24.4% to 63.3%). Six patients died of transplant-related complications and six died of disease relapse. Remission status at the time of BMT was the most important prognostic factor (P ‫؍‬ 0.005): no patient who received a transplant while their disease was not in remission survived, whereas the 5-year survival estimate for infants who underwent BMT during remission was 56% (95% CI, 31% to 75%). Long-term outcomes in the 10 infant survivors were compared with those of 10 older controls matched for diagnosis, disease status at the time of BMT, calendar year at the time of BMT, and source of stem cells. Immune function 1 year after transplantation and the incidences and spectra of late sequelae were similar for both groups during a median of 3.5 years (range, 1.5 to 7.2 years) of follow-up. Bone Marrow Transplantation (2001) 27, 717-722. Keywords: allogeneic transplantation; infant leukemia; myelodysplastic syndrome; late sequelaeThe incidences of lymphoid and myeloid leukemias in infants are approximately equal. Acute lymphoblastic leukemia (ALL) in infants accounts for 2.5% to 5% of all cases of childhood ALL, and acute myeloid leukemia (AML) in infants accounts for 6% to 14% of all cases of childhood AML. 1 The frequent presence of poor prognostic factors such as 11q23/MLL rearrangement in ALL and a high leukocyte count at the time of diagnosis of AML results in an overall long-term survival of only approxiCorrespondence: WH Leung,

A 21-year-old white male with relapsed acute lymphoblastic leukemia (ALL) developed an invasive Zygomycosis infection 3 weeks after beginning re-induction chemotherapy. Because of the high risk of fatal recurrence of the fungal infection, neither long-term maintenance chemotherapy nor allogeneic hematopoietic stem cell transplant (HSCT) was considered appropriate. Because his ALL blasts expressed CD34 but lacked CD133, he received a CD133 selected autologous graft following high-dose consolidation chemotherapy. The patient survives in remission 19 months after HSCT.

Engraftment syndrome, autologous graft-versus-host disease (GVHD), and infection after autologous hematopoietic cell transplantation can have similar clinical presentations. Here, we describe a patient with refractory Ewing sarcoma who had recurrent skin rash after autologous hematopoietic cell transplantation. Although the rash was diagnosed as GVHD histologically, this case illustrates the diagnostic dilemma of distinguishing engraftment syndrome, autologous GVHD, or concomitant viral infection. Because therapy for these entities is different, distinguishing them is important. Establishment of diagnostic criteria and understanding of the pathophysiology of these entities may lead to better management and to improved therapy of refractory cancer.