Immunosuppressive therapy for patients with Down syndrome and idiopathic aplastic anemia.

Idiopathic aplastic anemia (AA) is a rare hematological complication of Down syndrome (DS). The safety and efficacy of immunosuppressive therapy (IST) in individuals with DS remain unknown. We used a standard regimen of IST, comprising antithymocyte globulin and cyclosporine A, to treat three children with DS and idiopathic acquired AA. Two patients achieved a hematological (complete or partial) response and became transfusion independent at the final follow-up. The third patient failed to respond to IST and underwent bone marrow transplantation from a human leukocyte antigen (HLA)-mismatched unrelated donor. None of the patients experienced severe or unexpected adverse events during IST. Our experience suggests that IST is a safe and reasonable treatment, even in individuals with DS who suffer from AA and lack an HLA-matched sibling donor.