Decision making: immunosuppressive treatment versus allogeneic bone marrow transplantation as first-line treatment of aplastic anemia

The choice of primary treatment should be based on the availability of an HLA-identical sibling, the age of the patient and the severity of the disease. Patients without a donor should be given immunosuppressive therapy (IS) as the first-line therapy. When there is an available matched donor, and for those under 50 years of age, bone marrow transplantation (BMT) is probably the treatment of choice. Some thought that a first course of IS could also be considered for those above the age of 40 with high neutrophil counts.

Bone marrow transplantation

HLA-matched sibling transplantation

Five- to 10-year survivals of about 90% have been reported following BMT (see Chapter 12). There are at least two reasons for the recent improvement in survival of transplant patients. These include decreased incidences of marrow graft rejection, and of acute graft-versus-host disease (GVHD), the latter through better GVHD prevention regimens, e.g., methotrexate and cyclosporin. Rejection has decreased, in turn, because of several changes in the management of patients with aplastic anemia who are candidates for BMT. One change has been the more judicious use of transfusions before transplant, which are known to sensitize patients to minor histocompatibility antigens on donor cells. Also, removing sensitizing white blood cells from transfusion products has contributed to a reduced risk of sensitization and subsequent marrow graft rejection. Finally, the immunosuppressive qualities of the conditioning programs used to prepare patients for transplant have improved.