Aplastic anemia: pathogenesis and treatment.

This review highlights some of the contributions that have appeared in the literature in the past decade on the pathogenesis and treatment of aplastic anemia (AA). This summary is brief because the field is vast, spaning from stem cell biology to stem cell disorders, from autoimmunity to transplantation, from graft-versus-host disease to late effects. The immune pathogenesis of AA is now based on several lines of evidence and will be discussed. Immunosuppressive therapy (IST) remains an important option for AA patients who are not candidates for transplantation. Favorable prognostic indicators for IST are young age and a short interval from diagnosis; the neutrophil count seems to have lost its predictive value with current antithymocyte globulin-cyclsoporin combination therapy. The outcome of allogeneic bone marrow transplantations has significantly improved in the past decade, particularly in the unrelated donor setting, to such an extent that treatment strategies may be affected. A short interval between diagnosis and treatment will also improve results for bone marrow transplantation; these rare patients should be referred to an experienced center immediately.