Successful Second Unrelated Donor Hematopoietic Stem Cell Transplant in a Patient With Dyskeratosis Congenital After First Graft Rejection.

Dyskeratosis congenita is a rare congenital telomeropathy characterized by cutaneous and nail dystrophy, oral leukoplakia, and bone marrow failure. Pulmonary fibrosis and cancers are late manifestations. Allogeneic hematopoietic stem cell transplant represents the only cure for those with bone marrow failure with this disease, but outcomes reported are overall poor, with organ toxicities, graft failure, and graft-versus-host disease as main issues. Although reduced intensity conditioning regimens seem to be related to better outcomes, a standard regimen for dyskeratosis congenita has never been defined. Here, we report a successful long-term outcome of an 8-year-old girl with dyskeratosis congenita who received 2 consecutive allogeneic hematopoietic stem cell transplants from different unrelated donors, because of rejection after the first one, both conditioned with fludarabine-based reduced intensity conditioning regimen. The second transplant was complicated by severe hemorrhagic cystitis and acute grade IV graft-versus-host disease in the early phase and mild chronic graft-versus-host disease and ureteral stenosis in the late phase. This experience confirms that dyskeratosis congenita is at high risk for transplant-related morbidity but that a fludarabine-based reduced intensity conditioning regimen is a safe and feasible option as a preparative regimen, as shown here in a second transplant after first graft rejection. To reduce the risk of graft-versus-host disease, more effective prophylaxis schedules should be chosen in cases of unrelated donor, and haploidentical hematopoietic stem cell transplant with in vitro α/ β + and CD19+ depletion should be considered.