Introduction
Bone marrow transplantation (BMT), when HLA-identical siblings are available, and immunosuppressive therapy are the main therapeutic modalities currently used to treat pediatric patients with acquired aplastic anemia. Children who fail to respond can be treated with alternative therapies, including transplantation of bone marrow from unrelated or mismatched family donors and, more recently, hemopoietic growth factors. Reports on the outcome of immunosuppressive therapy in children are often controversial. Some authors have illustrated good response rates in adults and children older than 5 years, while others have shown the opposite (Doney et al., 1997; Matloub et al., 1994). When choosing which therapy to use to treat children with severe aplastic anemia (SAA), one should consider the possible late effects that are peculiar to pediatric patients, such as growth failure and other endocrine problems, as well as the risk of malignancies, which may occur if the conditioning regimen before BMT involves irradiation.
This chapter will cover the results and possible consequences of these treatments in childhood acquired aplastic anemia.
BMT from HLA-identical siblings
Allogeneic BMT from an HLA-identical sibling is thought to be the main treatment choice for young patients with acquired SAA. We analyzed the results of this therapeutic procedure in a large series of pediatric patients (less than 16 years of age) treated in Europe between 1970 and 1996. The SAA Registry of the European Blood and Marrow Transplantation Group (EBMT) contains data on 935 such patients, of whom 497 have received transplants from an HLA-identical sibling.