UMBILICAL-CORD BLOOD TRANSPLANTATION FROM UNRELATED DONORS IN AN ADULT WEIGHING 90 KILOGRAMS - ROLE OF IMMUNOSUPPRESSION IN ENGRAFTMENT

A 40-year-old male weighing 90 kilograms was diagnosed with acute myel oblastic leukaemia M5a which was resistant to chemotherapy, Neither a related nor an unrelated HLA-compatible bone marrow donor could be fou nd, A unit of cord blood was found with an HLA compatibility of four o ut of six loci, and was infused after conditioning with cyclophosphami de, total body irradiation and antilymphocyte globulin, The infused co rd blood had 0.98 x 10(7) nucleated cells per kilogram, On day 35 afte r infusion the patient was considered to have graft failure, A second unit of cord blood was found, and after 3 days of antilymphocyte globu lin, it was infused (day 41). The course was complicated by severe hyp oxia and bilateral interstitial pulmonary infiltrates, and the patient was treated with high doses of methylprednisolone. On day 58 the leuk ocyte count increased to 3 x 10(9)/l, and there was total chimerism of the first cord blood unit infused, Two weeks later leukocyte counts d ecreased progressively and the patient died of a disseminated fungal i nfection. We discuss the importance of the number of nucleated cells p er kilogram of body weight infused, and the role of intensive immunosu ppression in engraftment of cord blood transplantations in adults.