Abstract 898

Dyskeratosis congenita (DC) is a rare inherited syndrome characterized by reticulated hyperpigmentation of skin, dystrophic nails, and mucous membrane leukoplakia. Approximately 50% of patients develop aplastic anemia in the 2nd decade of life, and approximately 10% develop cancer in the 3rd to 4th decades of life. Prognosis is poor with predicted median age of survival in most to age 32 to 33 years. Death is usually secondary to hematological complications or malignancy. Therapies tried in the past for the bone marrow failure include androgens, prednisone, splenectomy, hematopoietic growth factors, and bone marrow transplantation (BMT), all with variable success. In reviewing the literature, 20 cases of allogeneic BMTs have been described, and to our knowledge, there has been no detailed report of an unrelated placental/umbilical cord blood cell transplantation (UCBCT) for DC. We performed an unrelated UCBCT in a 20 month old male with DC and bone marrow failure who lacked an HLA matched related donor. The patient was given a pre-transplant regimen of busulfan (40mg/m2/dose po q 6h × 16 doses), cyclophosphamide (50mg/kg/dose IV qd × 4 doses), and antithymocyte globulin (30mg/kg/dose IV qd × 3 doses). The UCBC unit was from a female donor and was mismatched at one HLA-B locus (donor B8,50; recipient B49,8). The UCBC graft contained 7.9 × 107 nucleated cells. Intravenous cyclosporine and methylprednisolone were given as post-UCBCT prophylaxis against acute graft versus host disease (GVHD). The total leukocyte count exceeded 1 × 109/l and the absolute neutrophil count exceeded 0.5 × 109/l at 18 days after transplant. The platelet count was greater than 20 × 109/l at 70 days after transplant. There has been no clinical or laboratory evidence of GVHD. Post-transplant complications have been largely related to infections and have included herpes zoster, Clostridium difficile colitis, and bacteremia with Bacillus species, Enterococcus faecalis, and Staphylococcal epidermidis. Currently, the patient is 6 months post-transplant with full hematologic reconstitution. We conclude that an unrelated UCBCT should be considered in patients with DC and bone marrow failure who lack a suitable HLA matched related marrow donor. Long-term follow-up in these patients is important because of the increased risk of development of neoplastic diseases. Patients with DC should be followed on a regular basis even though hematopoietic transplantation has corrected their cytopenias.