[Haploidentical transplantation from a related donor as first-line treatment for fulminant aplastic anemia]

Immunosuppressive therapy (IST) is the first-line treatment for young patients with severe aplastic anemia (AA) when a human leucocyte antigen (HLA)-matched related donor (MRD) is unavailable. Fulminant AA (FAA) is defined as AA with a complete absence of neutrophils at presentation and no response to granulocyte-colony stimulating factor (G-CSF) treatment. Here we report a 38-year-old male FAA patient who underwent allogeneic stem cell transplantation from an HLA haplotype-mismatched donor as first-line treatment. The patient had no remarkable disease history and was referred to our hospital because of a peritonsillar abscess and severe pancytopenia. Bone marrow biopsy revealed marked hypocellularity without dysplasia. His neutrophil count remained 0.0×10⁹/l following G-CSF administration, and he was diagnosed with FAA. His siblings were not MRDs, but his sister had haploidentical HLAs. After administering a conditioning regimen, the patient received a transplant of peripheral blood stem cells donated by his sister. Neutrophil engraftment was observed on post-transplant day 16, and he experienced acute graft-versus-host disease (grade I, skin stage 1), but no other complications were observed. Hematopoietic stem cell transplantation from an HLA haplotype-mismatched related donor may be a viable option for first-line treatment of FAA when an MRD is unavailable.