Therapeutic decision making in BMT/SCT for congenital immunodeficiencies

Introduction Among the early successes of allogeneic BMT were those achieved in the area of congenital immunodeficiencies. In certain diseases and certain donor– recipient combinations, over 90% of patients can be cured by allogeneic transplantation. Worldwide, over 3000 patients with congenital immunodeficiencies have been treated by allogeneic transplantation. The following table gives a list of the current indications. Patients with congenital immunodeficiencies generally manifest as severe infections within the first year of life. In the absence of a hematopoietic stem cell or bone marrow transplantation most severe immunodeficiencies are fatal. The European Society for Immunodeficiencies (ESID) in collaboration with the European Group for Blood and Marrow Transplantation provides guidelines for the conditioning regimens in use for primary immunodeficiencies (www.esid.org and www.ebmt.org). For reviews related to BMT and congenital immunodeficiencies see Buckley et al., 1999; Buckley, 2003; and Steward et al., 2005. With the advent of genetic mapping, SCID is now increasingly classified on a genetic basis. This gives a more precise characterization of the immunological defects. Thus it is becoming clear which types have the best cure rate, allowing the stratification of therapy. Estimations of the incidence of immune deficiency syndromes vary widely. On the basis of registry reports, an incidence of 1:70,000 to 1:1,000,000 live births is suggested.