Nonmyeloablative allogeneic bone marrow transplantation for treatment of childhood overlap syndrome and small vessel vasculitis.

A 13-year-old Caucasian female with a systemic connective tissue disease (overlap syndrome with pulmonary vasculitis) underwent nonmyeloablative allogeneic BMT after failure of prolonged combination immunosuppressives to induce remission. The procedure also included cotransplantation of donor bone chips as a source of stromal cells. The unique protocol allowed good engraftment of hematopoietic (>95%) and bone core stromal cells (>60%). The patient was clinically improved, stable, and off all immunosuppressive medications 36 months post-transplant. To our knowledge, this is the first pediatric nonmyeloablative BMT with cotransplantation of stromal cells solely for treatment of an autoimmune disease.