TY - CHAP M1 - Book, Section TI - Polyclonal and Hereditary Sideroblastic Anemias A1 - Ponka, Prem A1 - Prchal, Josef T. A2 - Kaushansky, Kenneth A2 - Lichtman, Marshall A. A2 - Prchal, Josef T. A2 - Levi, Marcel M. A2 - Press, Oliver W. A2 - Burns, Linda J. A2 - Caligiuri, Michael PY - 2015 T2 - Williams Hematology, 9e AB - SUMMARYSideroblastic anemias are characterized by the presence of ring sideroblasts in the marrow. These cells are erythroid precursors that have accumulated abnormal amounts of mitochondrial iron. A variety of abnormalities of porphyrin metabolism in affected erythroid cells have been documented. Hereditary sideroblastic anemias are usually X linked, as the result of mutations in the erythroid form of 5-aminolevulinic acid synthase. Inherited autosomal and mitochondrial forms are seen, occasionally. Acquired sideroblastic anemias can occur as a result of the ingestion of drugs, alcohol, or toxins such as lead or zinc, or copper deficiency. Patients with acquired sideroblastic macrocytic anemia and variable degrees of thrombocytopenia and leukopenia from copper deficiency have been recognized more frequently; the hematologic abnormalities typically resolve after copper replacement. Ring sideroblasts are also a feature of myelodysplastic neoplasms, and are discussed in Chap. 87. Some patients with sideroblastic anemia may respond to pharmacologic doses of pyridoxine. Iron loading is common in the sideroblastic anemias and can be treated by phlebotomy when the anemia is mild or with iron chelators (Chap. 43) when it is more severe. SN - PB - McGraw-Hill Education CY - New York, NY Y2 - 2024/04/18 UR - hemonc.mhmedical.com/content.aspx?aid=1121095397 ER -