[Differential diagnosis of inherited bone marrow failure syndromes in erythrocyte disorders]

Diamond-Blackfan anemia (DBA), congenital dyserythropoietic anemia (CDA), and inherited sideroblastic anemia (ISA) are representative diseases of inherited bone marrow failure syndromes in erythrocyte diseases. DBA is primarily caused due to ribosomal dysfunctions. Furthermore, reticulocytes and erythroid progenitor cells decrease considerably within the peripheral blood and bone marrow, respectively. CDA is caused by a disturbance in red blood cell maturation and ineffective erythropoiesis due to hemolysis in the bone marrow. CDA is mainly classified into types I to III, and multinucleated erythroblasts observed in the bone marrow, typically in the internuclear bridge in type I. ISA is caused by iron metabolism dysfunction in the mitochondria due to defective heme synthesis. Sideroblasts appear ringed due to iron accumulation in the mitochondria of erythroid precursors. Gene mutation analysis is indispensable for the confirmatory diagnosis of these diseases; however, narrowing down the diagnosis, by examining the erythrocytes in the peripheral blood and the erythroblast morphology in the bone marrow, is also important.