Allogeneic bone marrow transplantation in Chédiak-Higashi syndrome.

A boy with Chédiak-Higashi syndrome (CHS) treated by allogeneic bone marrow transplantation (BMT) is described. He had had several respiratory infections during his first 2 years of life, and at the age of 2.5 years he presented with an accelerated phase of CHS. Despite treatment with ascorbic acid and trimethoprim/sulfamethoxazole, he continued to experience recurrent bacterial infections. Allogeneic BMT was performed with his HLA- and mixed leukocyte culture-identical healthy brother as the donor. The preparative regimen consisted of busulfan and cyclophosphamide, and methotrexate and cyclosporine A were given as prophylaxis for graft-versus-host disease (GVHD). The patient engrafted well, and no symptoms or signs of acute GVHD developed. He then achieved chimerism status, in which half the peripheral blood neutrophils and some of the bone marrow myelopoietic cells displayed Chédiak-Higashi granules, and DNA analysis showed half the peripheral blood cells to be of donor origin and the other half to be of host origin. The boy is currently alive and well 24 months after transplant. Allogeneic BMT, even with mixed chimerism as a result, is a potentially curative therapy for CHS.