Is Busulfan and Fludarabine an Optimal Myeloablative Hematopoietic Stem Cell Transplant (HSCT) Conditioning Regimen in Children with AML/MDS ?

Successful Myeloablative Matched Unrelated Donor Hematopoietic Stem Cell Transplantation in a Young Girl With GATA2 Deficiency and Emberger Syndrome

Patients with GATA2 (Emberger syndrome) deficiency needs early hematopoietic stem cell transplant (HSCT) before evolving in to myelodysplastic syndrome or acute myeloid leukemia and with time given compromised organ dysfunction leads to increase regimen-related toxicities. Most published cases have used nonmyeloablative conditioning regimens, show higher incidences of rejection and relapse rates and umbilical cord blood transplant has been reported to be suboptimal in patients with GATA2 deficiency because of longer period of engraftment leads to more infections and mortality. We report a 4.5-year-old girl with GATA2 deficiency who underwent matched unrelated donor HSCT utilizing a myeloablative conditioning regimen including intravenous busulfan (total dose of 12.8 mg/kg) and fludarabine (total dose of 160 mg/m) She tolerated the conditioning regimen and bone marrow infusion well. Her initial chimerism was mixed (90% donor), cyclosporine was gradually weaned and discontinued at day+85 and this resulted in conversion to full-donor chimerism. Bone marrow assessment 3 months post-HSCT revealed normal hematopoiesis and absence of monosomy 7. At 20 months of follow-up she had full-donor chimerism with complete reconstitution of the all hematopoietic stem cells. Myeloablative matched unrelated donor HSCT represents an effective option for cure in patients with GATA2 deficiency and Emberger syndrome.