[Allogeneic hematopoietic stem cell transplantation for Shwachman-Diamond syndrome: a report of three cases and literature review]

This study reports on three patients with Shwachman-Diamond syndrome (SDS) who underwent allogeneic hematopoietic stem cell transplantation (allo-HSCT) at the First Affiliated Hospital of Zhejiang University School of Medicine. Based on relevant literature, the clinical manifestations and genetic mutation characteristics of SDS were summarized, and the efficacy and timing of allo HSCT for such patients were explored. Three SDS patients were all male, with transplant ages of 32, 33, and 32 years old, respectively. All three patients were diagnosed in childhood. Case 1 presented with anemia as the initial clinical manifestation, which gradually progressed to a decrease in whole blood cells; Case 2 and 3 both present with a decrease in whole blood cells as the initial clinical manifestation. Case 1 and 3 have intellectual disabilities, while case 3 presents with pancreatic steatosis and chronic pancreatitis. All three patients have short stature. Three patients all detected heterozygous mutations in the SBDS: c.258+2T>C splice site. The family members of the three patients have no clinical manifestations of SDS. All three patients were treated with a reduced dose pre-treatment regimen (Fludarabine+Busulfan+Me-CCNU+Rabbit Anti-human Thymocyte Globulin). Case 1 and case 2 underwent haploid hematopoietic stem cell transplantation, while case 3 underwent unrelated donor hematopoietic stem cell transplantation. Case 1 was diagnosed with myelodysplastic syndrome transforming into acute myeloid leukemia before transplantation, but experienced early recurrence and death after transplantation; Case 2 is secondary implantation failure, dependent on platelet transfusion; Case 3 was removed from medication maintenance treatment after transplantation, and blood routine monitoring was normal.