Anemias Hypochromic là nguyên mẫu hình thái của tất cả các anemias phát sinh từ một rối loạn tổng hợp hemoglobin trong hồng cầu. Trong trường hợp thiếu sắt nặng, hồng cầu nhỏ, phẳng, và tính năng một khu vực rộng lớn xanh xao trung tâm (anulocytes) | 80 Chapter IV Blood and Bone Marrow Disturbances of Erythropoiesis Hypochromic Anemias Fig. 23a-d Hypochromic anemias are the morphologic prototype of all anemias that arise from a disturbance of hemoglobin synthesis in erythrocytes. In cases of severe iron deficiency the erythrocytes are small flat and feature a large area of central pallor anulocytes Fig. 23a . Typically there is a left shift of erythropoiesis meaning that there is a predominance of younger basophilic forms. Nuclear-cytoplasmic dissociation is also present . the nucleus is relatively mature while the cytoplasm still appears strongly basophilic and may be poorly marginated Fig. 23b c . The quantitative changes in erythropoiesis can be quite diverse. Iron deficiency due to an acute or chronic blood loss is usually associated with a marked increase of erythropoiesis with a shift in the balance of erythropoiesis and granulocyto-poiesis in favor of red cell production. Additionally the megakaryocytes are usually increased in number. By contrast there is often an absolute reduction of erythropoiesis in toxic-infectious processes and neoplastic diseases chronic disease anemias although there are no hard and fast rules. The bone marrow changes found in iron utilization disorders sideroachrestic anemia iron deficiency without iron deficiency are similar to those observed in iron deficiency. They can be differentiated by iron staining see p. 9 . In the iron deficiency anemias Fig. 23a-d it is rare to find siderocytes and sideroblasts and iron deposits are never detected in macrophages Fig. 23d . On the other hand sideroachrestic anemias are characterized by numerous sideroblasts with coarse granular iron deposits ringed sideroblasts Fig. 61 and massive iron storage in the macrophages see myelodysplastic syndromes refractory anemia with ringed sideroblasts RARS . Iron-storing cells can also be found in infectious and neoplastic anemias. The various forms of iron deficiency and their .
