Acquired Aplastic Anemia

Aplastic anemia manifests with pancytopenia and a hypocellular bone marrow. The disease may be acquired or inherited. Most cases of acquired aplastic anemia result from autoimmune destruction of hematopoietic stem/progenitors and respond to immunosuppressive therapies. The inherited forms of aplastic anemia are less common and usually present within the first decade of life. Inherited bone marrow failure may be due to a variety of genetic mutations such as DNA repair defects (Fanconi anemia), telomerase defects (dyskeratosis congenita), ribosomopathies (Schwachman-Diamond syndrome), or cMPL mutations (amegakaryocytic thrombocytopenia). Immunosuppressive therapy is not helpful for most inherited forms of bone marrow failure. This chapter will predominantly focus on acquired aplastic anemia; however, it is important to be aware of these less common inherited forms of aplastic anemia since they can sometimes be hard to distinguish from the acquired form of the disease.