Kinetics of erythroblast proliferation in states of hypoferremia.

By application of the method of quantitative 14C-autoradiography, the kinetics of erythroblast proliferation were studied in seven patients with iron-deficiency anemia (IDA), in five cases of anemia associated with infection or malignancy (ACD), and in two patients with bleeding anemia (BLA). The turnover rate of erythroblasts was significantly reduced in IDA and ACD, and was normal in BLA. Proliferation and maturation of erythroblasts in IDA and ACD were increasingly slowed down with advancing development into mature cells. Neither changes in the number of cell divisions nor ineffective erythropoiesis were observed within the proliferative compartments. The kinetic impairments found in IDA and ACD could readily be counterbalanced by a twofold increase in the rate of stem cell differentiation. Within recognizable erythropoiesis, no compensatory effort was detectable, not even in proerythroblasts. Insufficient compensation at the stem cell level is therefore regarded as the prime lesion in IDA and ACD.