Changing Epidemiology of Infections in Children and Adolescents After Autologous and Allogeneic Hematopoietic Stem Cell Transplantation

Advances in autologous and allogeneic hematopoietic stem cell transplantation (HSCT) over the past 20 years may have had an impact on the morbidity and mortality associated with infections post-transplant. We sought to retrospectively analyze the epidemiology and risk factors for bacterial, fungal, viral, and parasitic infections 0-30 days post-transplant in a cohort of 385 autologous and 759 allogeneic pediatric HSCT recipients transplanted in a single institution between1990 to 2009. Risk factors were evaluated using logistic regression. Infections occurred in 98 (25%) autologous compared to 307 (40%) allogeneic HSCT patients. Gram-positive bacterial infections were more prevalent than gram-negative bacterial infections in both autologous (P = .003) and allogeneic (P < .0001) HSCT patients. Bacteremia occurred in 31 (8%) autologous and 59 (8%) allogeneic HSCT patients. Autologous HSCT patients with a diagnosis of leukemia were at a higher risk for bacterial infections compared to those with solid tumors (P = .004, OR 2.80, 95% CI 1.39-5.66). Infections due to fungal and parasitic pathogens in autologous HSCT patients were uncommon, and occurred exclusively prior to 2000. Candidemia was detected in 26 (3%) and aspergillosis in 49 (6%) allogeneic recipients. Herpes-Simplex virus was the most common cause of viral infections in both autologous and allogeneic recipients. Cytomegalovirus donor/recipient status increased risk for all viral infections for allogeneic HSCT recipients (P=.0004). Only 3 (0.8%) deaths were attributed to infection after autologous HSCT. All occurred prior to 2000 in patients transplanted for acute myeloid leukemia. There were 8 (1%) allogeneic HSCT patients who died of infections 0-30 days post-transplant. This is the largest retrospective study on the changing epidemiology of infections after autologous and allogeneic HSCT in children and adolescents.