[Fractionated bone marrow transplantation in a case of severe combined immunodeficiency].

Authors present a male infant affected by severe combined immunodeficiency with a high percentage of circulating B lymphocytes. Pathogenetic mechanism underlying our patient's disease seems to be an intrinsic defect in the lymphoid stem cell. As no histocompatible donor could be found, an hemiallogeneic bone marrow transplantation of maternal origin, fractionated with soybean agglutinin, was performed. The patient died 27 days after transplantation. At this time the percentage of T cells in his peripheral blood rose to near normal values, and the percentage of B cells normalized, karyotype analysis demonstrated circulating cells of female origin. Necropsy showed a spleen with lymphoid follicles and germinal centres but no signs of graft-versus-host could be found. Fractionated bone marrow could be of paramount importance in the treatment of these patients, since it could circumvent graft-versus-host disease.