Anemia in myelodysplastic syndrome
In myelodysplastic syndrome Myelodysplastic Syndrome (MDS) The myelodysplastic syndrome (MDS) is group of clonal hematopoietic stem cell disorders typified by peripheral cytopenia, dysplastic hematopoietic progenitors, a hypercellular or hypocellular... read more , anemia is commonly prominent. The anemia is usually normocytic or macrocytic, and a dimorphic (large and small) population of circulating cells can be present. (See also Overview of Decreased Erythropoiesis Overview of Decreased Erythropoiesis Anemia, a decrease in the number of red blood cells (RBCs), hemoglobin (Hb) content, or hematocrit (Hct), can result from decreased RBC production (erythropoiesis), increased RBC destruction... read more .)
Bone marrow examination shows decreased erythroid activity, megaloblastoid and dysplastic changes, and, sometimes, increased numbers of ringed sideroblasts.
Treatment is directed at the malignancy, and growth factors may be used.
Iron-transport deficiency anemia
Iron-transport deficiency anemia (atransferrinemia) is exceedingly rare. It occurs when iron cannot move from storage sites (eg, mucosal cells, liver) to the erythropoietic precursors. One well-known form is iron-refractory iron deficiency anemia (IRIDA), caused by germline mutations in the TMPRSS6 gene, which encodes a transmembrane protein that regulates production of hepcidin, a protein involved in iron absorption.
Patients have a microcytic anemia with very low transferrin saturation and are refractory to oral iron. Because hepcidin regulation is defective, hepcidin levels are inappropriately elevated despite iron deficiency.
Treatment of IRIDA is usually with IV iron preparations, although only partial responses typically occur. Prolonged courses of oral iron together with vitamin C may also be attempted.
