Unexpected complications after bone marrow transplantation in transfusion-dependent children.

Ten patients on transfusion-chelation programs were treated with bone marrow transplantation (BMT). The busulfan-cyclophosphamide conditioning regimen was inadequate in the 6 beta thalassemia major patients, resulting in marrow rejection problems for 3. Post BMT one patient remains with thalassemia major and two have mixed chimerism with a clinical status of thalassemia intermedia. Three patients have thalassemia minor from their donors, but one required a second BMT to achieve this state. Two of the four Diamond Blackfan Syndrome patients died of BMT-related complications. Two achieved normal hematopoiesis, one at the price of chronic graft vs host disease. Because of the excellent results of iron chelation in our patients, we question whether such patients with access to the state of the art transfusion-chelation programs should continue to be transplanted. This situation requires continuing evaluation.