Management of infections complicating allogeneic hematopoietic stem cell transplantation

The use of allogeneic hematopoietic stem cell transplantation for the treatment of hematologic malignancies, as well as some benign hematologic disorders, has continued to grow over the last 10 years. The availability of this procedure to an increasing number of patients has been facilitated by the use of newer techniques, including reduced intensity conditioning (RIC) regimens, peripheral blood stem cells (PBSCs) and cord blood as donor sources, graft manipulation such as selective T-cell depletion, and other in vitro and in vivo attempts to reduce the risk and severity of graft-versus-host disease (GVHD) after transplantation without losing the potential benefits of a graft-versus-tumor effect for patients with hematologic malignancies. The underlying theme of many of these newer techniques has been to minimize the severity and duration of transplant-related immune suppression, thus reducing the risk of morbidity and mortality from infectious complications. This article reviews immune suppression and recovery that occur after allogeneic stem cell transplantation, with changes in the epidemiology, and some of the recent advances that have been made in management of infectious complications.