Characterized by the production of red blood cells that is smaller than normal.
Microcytic red cells are due to decreased production of hemoglobin.
Causes of microcytic anemia are lack of globin reduction, as in thalassemia, restricted iron delivery to the heme group of hemoglobin, as anemia of inflammation, a lack of iron delivery to the heme group, as an iron deficiency anemia and defects in the heme group synthesis, such as with sideroblastic anemia.