Haploidentical related umbilical cord blood stem cell transplant in a child with acute non-lymphocytic leukemia

Abstract

Umbilical cord blood stem cells (UCBSC) were used to reconstitute hematopoiesis following myeloablative therapy in a 13-month-old infant with acute nonlymphocytic leukemia (ANLL):FAB-M5 who had failed to sustain a chemotherapeutic remission. The patient’s mother was 18 weeks pregnant with her second child at the time of diagnosis. Amniocentesis revealed that the fetus was HLA-haploidentical with the patient at the paternally inherited allele. The umbilical cord blood was harvested and processed by Ficoll centrifugation with 100% recovery of 5 × 10⁷ mononuclear cells/kg and then cryopreserved. Two weeks after collection the cells were thawed and then infused into the patient following conditioning with total body irradiation, cyclophosphamide, and etoposide. Graft-versus-host-disease (GVHD) prophylaxis consisted of cyclosporine and methotrexate. The patient experienced clinical grade I GVHD consisting of skin involvement only that resolved within 2 weeks following the addition of corticosteroids. Engraftment was achieved with an absolute neutrophil count (ANC) above 0.5 × 10⁹/l on day 16, a platelet count above 50 × 10⁹/1 on day 56, platelet transfusion independence on day 32 and red blood cell transfusion independence after day 44. Three months following transplantation restriction fragment length polymorphisms (RFLP) revealed no discernible difference between the donor and the recipient. The patient remains in remission without evidence of GVHD 23 months post-transplant.