Transplant parameter | Effect on host barriers and immunity | Infectious consequences |
Type of transplant | Allogeneic: slower B and T cell immune reconstitution | Greater risk for infections of all types, but especially invasive fungal and herpesvirus infections; longer interval of risk |
Type of allogeneic donor | Unrelated or mismatched donor: slower B and T cell immune reconstitution | Greater risk for infections of all types, but especially invasive fungal and herpesvirus infections; longer interval of risk |
Type of stem cell graft | Peripheral blood: faster neutrophil engraftment, more chronic GVHD Cord blood: slower neutrophil engraftment, less GVHD, slower B and T cell immune reconstitution | Different risks for infections associated with neutropenia and GVHD |
Stem cell graft manipulation | T cell depletion: greater risk for graft rejection, slower B and T cell immune reconstitution | Greater risk for neutropenic infections, lower risk for infections associated with chronic GVHD, greater and longer risk for herpesvirus and invasive fungal infections |
Conditioning regimen | Intensive regimens: more mucosal injury, shorter time to neutropenia and longer period of neutropenia | Greater risk for neutropenic infections, especially neutropenic enterocolitis (typhlitis) |
Immunosuppressive regimen (allogeneic) | ATG: more profound deficiency of T cell immunity Methotrexate: more mucosal injury, longer time to neutrophil recovery | Greater risk for invasive fungal and herpesvirus infections |
Central venous catheter | Breach in skin barrier | Greater risk for bacterial and (less frequently) fungal infections |