Hematopoietic Stem Cell Transplantation

Hematopoietic stem cell transplantation (HSCT) has become increasingly accepted as a therapeutic modality for a variety of malignant and nonmalignant conditions. Diseases treated using HSCT can be divided into malignant and nonmalignant conditions. Stem cells for allogeneic transplantation are collected from bone marrow, peripheral blood, or umbilical cord blood, whereas stem cells for autologous transplantation are collected most commonly from peripheral blood. Many other minor histocompatibility complexes are important in the immune response; however, current donor matching for HSCT is limited to class I and II molecules. Due to the pretransplant preparative regimen, patients will have an extended period of anorexia requiring total parenteral nutrition. The profound immunosuppression that occurs both before and after engraftment puts HSCT patients at high risk for infection with a variety of organisms. Even with the recovery of white blood cell counts and specifically lymphocyte counts, HSCT patients take months to years to recover immune function.