It was reported that at a hypothyroidism the lump of erythrocytes decreases, but these changes can mask to a certain degree parallel decrease in volume of plasma. Both research of marrow, and studying of kinetics of iron demonstrate oppression of an erythrogenesis which is probably caused by reduced consumption by fabrics of oxygen and reduction of metabolic activity. It is considered that as a result of indirect action of these factors on erythropoetin secretion its level falls, thyroxine, apparently, does not stimulate an erythrogenesis. However, it is difficult to insist on these statements as it is impossible to determine erythropoetin level in normal plasma and, therefore, to confirm falling of its level. Besides, there are bases to assume that hormone of a thyroid gland renders the direct stimulating effect on growth of eritropoetinzavisimy erythroidal colonies.
Anemia proceeds softly, is often increased by MCV, and in a blood smear the wrinkled erythrocytes of irregular shape occasionally are found. In marrow signs of an erythroidal hypoplasia come to light, and researches of kinetics of iron indicate that they its clearance from plasma and utilization during maturing of erythrocytes are reduced. At patients with a hypothyroidism atrophic gastritis and the related deficit of iron or B12 vitamin because of what the clinical picture can change often take place. We will not discuss these features here, but at a hypothyroidism it is necessary to remember a possibility of their emergence.
Treatment by thyroxine leads to slow, but steady normalization of all parameters, however the accompanying deficit of iron or B12 vitamin demand the corresponding replacement therapy.