Hematopoietic stem cell transplantation for complete IFN-γ receptor 1 deficiency: A multi-institutional survey

To evaluate the outcome of hematopoietic stem cell transplantation (HSCT) in a series of patients with inherited complete IFN-γ receptor 1 (IFNγR1) deficiency. We report 8 patients who received altogether 11 HSCT from family donors, including 10 HLA-identical (5 siblings and 5 relatives) and 1 HLA-haplo-identical donors. Five grafts were T-cell depleted, and conditioning regimens varied in intensity. Four patients died within 8 months after HSCT. Two of these deaths were due to specific complications related to mycobacterial infection. There was no or very low (2%) donor cell engraftment in 2 survivors. Only 2 patients are in full remission of mycobacterial disease 5 years after HSCT. These are the only patients who received non–T-cell–depleted grafts from an HLA-identical sibling after a fully myeloablative conditioning regimen. HSCT can lead to prolonged remission of mycobacterial disease in children with complete IFNγR1 deficiency. However, optimal control of mycobacterial infection before HSCT and the use of a non–T-cell–depleted transplant from an HLA-identical sibling after a fully myeloablative conditioning regimen are recommended.