Prenatal molecular diagnosis and allogeneic hematopoietic stem cell transplantation in an infant with RAG2 deficiency

RAG2 deficiency is a cause of severe combined immunodeficiency (SCID), characterized by a defect in the development of T and B lymphocytes that predisposes patients to life-threatening infections during the first months of life. We present the case of an infant with a prenatal molecular diagnosis of SCID secondary to RAG2 deficiency who underwent allogeneic hematopoietic stem cell transplantation (HSCT) using a human leukocyte antigen-identical sibling donor at 3 months old. The subsequent clinical course was favorable, with successful immune reconstitution. This case highlights the impact of prenatal molecular diagnosis on the implementation of preventive measures, the performance of early HSCT, and the optimization of clinical outcomes in patients with RAG2 deficiency.