Sideoblastic anemia

Sideoblastic anemia due to impaired iron utilization and, as a rule, are part of myelodysplastic syndrome, normocytic-normochromic anemia with a high red blood cell scatter by volume (RDW) or microcyto-hypochromic anemia with elevated serum iron, ferritin and saturation of transferrin.

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Causes of the sideroblastic anemia

Sideoblastic anemia, among other anemias, is characterized by inadequate utilization of iron for hemoglobin synthesis, despite the presence of a normal or elevated level of iron (impaired iron utilization). Other anemia with impaired iron utilization include some hemoglobinopathies, especially thalassemia. Sideoblastic anemia is characterized by the presence of polychromatophilic, granular, target-like erythrocytes (siderocytes). Sideroblastic anemia is part of myelodysplastic syndrome, but it can be congenital or secondary after taking medication (chloramphenicol, cycloserine, isoniazid, pyrazinamide) or toxins (including ethanol and lead). There is a deficiency in the production of reticulocytes, intraosseous cerebral erythrocyte death and bone marrow erythroid hyperplasia (and dysplasia). Although hypochromic erythrocytes are also produced, other erythrocytes can be large in size, which leads to normochromic indicators, thus, the erythrocyte size variability (dimorphism) usually corresponds to a high RDW value.

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Symptoms of the sideroblastic anemia

In myelodysplasia, anemia is typical. Anemia can be microcytic or normochromic-normocytic, usually with a dimorphic (large and small) cell population. A bone marrow study demonstrates a decrease in erythroid activity, megaloblastoid and dysplastic changes, and often an increase in the number of ring sideroblasts. Anemia associated with iron transport deficiency (atransferrinemia) is extremely rare. It manifests itself when iron cannot be transported from storage sites (for example, cells of the liver mucosa) to erythropoietic precursors. A possible mechanism is the absence of transferrin or an anomaly of the transferrin molecule. Additional signs are the hemosiderosis of the lymphoid tissue, especially along the gastrointestinal tract.

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Diagnostics of the sideroblastic anemia

Sideroblastic anemia is suspected in patients with microcytic anemia or anemia with high RDW, especially with elevated levels of serum iron, serum ferritin and transferrin saturation. A peripheral blood smear demonstrates erythrocyte dimorphism. Red blood cells may be granular. The study of bone marrow is mandatory and is manifested by erythroid hyperplasia, coloring on iron reveals mitochondria (ring sideroblasts) surrounded by iron in developing erythrocytes. Other signs of myelodysplasia often appear. When an obscure cause of sideroblastic anemia is conducted, research is conducted for the presence of lead in serum.

[12], [13], [14], [15], [16], [17]

Treatment of the sideroblastic anemia

The elimination of toxins or medications (and in particular the cessation of alcohol intake) can lead to the restoration of hemopoiesis. In rare cases, congenital pathology responds to pyridoxine at a dose of 50 mg orally 3 times a day, but the answer is not complete.