[Successful immunosuppressive therapy for a patient with hypoplastic myelodysplastic syndrome].

We encountered a patient with hypoplastic myelodysplastic syndrome (MDS) who responded to immunosuppressive therapy including antithymocyte globulin and cyclosporin A (CsA). A 13-year-old girl was referred to our hospital because of pancytopenia. Bone marrow smears disclosed extreme hypocellularity without cellular atypism. A diagnosis of aplastic anemia was made, and immunosuppressive therapy consisting of ATG, CsA, granulocytecolony-stimulating factor (G-CSF), methylprednisolone, and danazol was started. A month later dysplastic cells appeared in the bone marrow. The karyotype of pretreatment bone marrow cells was 46, XX, del (13) (q12; q14). Therefore, the final diagnosis was hypoplastic MDS. CsA and danazol were continued. The patient became transfusion-independent 1 month later and dysplastic cells disappeared from bone marrow 3 months later. The chromosomal abnormality also became undetectable 6 months after the initiation of treatment. These findings indicated that immunosuppressive therapy is beneficial for patients with hypoplastic MDS.