Matched unrelated bone marrow transplantation for combined immunodeficiency

Bone marrow transplantation (BMT) from siblings is the treatment of choice for severe combined immunodeficiency (SCID), The objective of this study wa s to evaluate the efficiency of BMT from matched unrelated donors (MUD) in congenital immunodeficiencies when a sibling donor is unavailable. Sixteen consecutive patients with SCID (n = 9) and CID (n = 7), were referred for a n unrelated donor search. Acceptable donors were found for all patients. Fi fteen patients received busulfan and cyclophosphamide pretransplant conditi oning. One patient had an early loss of graft and was reconditioned using c yclophosphamide and total body irradiation. The graft-versus-host disease ( GVHD) prophylaxis used was methylprednisolone, cyclosporin A with or withou t methotrexate. Neutrophil engraftment was rapid and was achieved in all pa tients within a mean of 15.4 days. Only 13 episodes of fever were recorded shortly after BMT. GVHD of grade II or more was apparent in 2/9 (22%) of SC ID patients and in 4/7 (57%) of CID patients, Overall survival was 75% with a mean follow-up of 47.4 months (range 18-101). Six out of nine SCID patie nts (67%) and 6/7 (86%) of CID patients are alive and well. Eleven patients had normal humoral immunity, and cell-mediated immunity as measured by flo w cytometry and mitogenic responses, was intact in all patients. Intraderma l candida skin test was positive in 9/10 patients tested, We conclude that BMT from MUD results in rapid engraftment and is therefore associated with a low rate of infection contributing to the improved survival rate. The pro tocol used is especially favorable for patients with combined immunodeficie ncy.