'Auto'-immune neutropenia after allogeneic bone marrow transplantation unresponsive to conventional immunosuppression but resolving promptly after splenectomy.

A 32-year-old male presented with isolated neutropenia 6 months after allogeneic bone marrow transplantation for CML from his HLA-matched brother. The presence of granulocyte-specific IgM and IgG antibodies in the patient's serum indicated an immune-mediated basis for the neutropenia. A variety of manoeuvres to suppress antibody production or to reduce peripheral destruction, including high-dose intravenous immunoglobulins 400 mg/kg (total 24 g) on 5 consecutive days, prednisolone 80 mg for 10 d and plasmapheresis on 3 consecutive d, failed to raise the neutrophil count. Splenectomy, however, resulted in a prompt and sustained rise of neutrophils to normal values.