[Dyserythropoiesis and dyserythropoietic anemias]

The expression "congenital dyserythropoietic anemia" (CDA) has been used to characterize the kinetic and morphological aberrations in the proliferation and maturation compartment of erythropoiesis, occurring in a group of hereditary anemias of unknown pathogenesis. The main symptoms of these disorders are moderate or mild anemia, increased hemoglobin turnover, ineffectiveness of erythropoiesis, striking morphological aberrations of the erythroblasts and tendency to secondary hemochromatosis. To date, three types have emerged from this group that may be hereditary nosological entities. They are distinguished not only on a morphological basis, but also by different modes of inheritance and immunological properties of the red cell membrane. A number of additional cases or families have been described which could not be attributed to one of these three types. Comparative investigations of morphological, biochemical and immunological details in CDA on the one hand, and other forms of ineffective erythropoiesis (e.g. thalassemia, refractory anemia) on the other demonstrate the lack of specificity of many of the single changes observed in CDA. These changes may well be secondary phenomenon of intramedullary cell destruction brought about by different underlying pathogenetic mechanisms.