Sideroblastic Anemia

Sideroblastic anemia (SA) is a familial or congenital or acquired anemia, which represents a diverse group of disorders characterized by increased ring sideroblasts in bone marrow. Ring sideroblasts are erythroblasts with pathogenic iron-laden mitochondria encircling their nucleus. Morphologically, ring sideroblasts are defined by having a minimum of 5 siderotic granules covering at least one-third of the circumference of the nucleus of erythroblasts. Ring sideroblasts should be distinguished from sideroblasts. The latter is iron deposition inside cytoplasm of erythroblasts, usually not riming nuclei and does not meet the above criteria to be called ring sideroblasts.