Ferrokinetics and erythropoiesis in man: red-cell production and destruction in normal and anaemic subjects.

Recent advances in the analysis of plasma 59Fe clearance have produced a unified method for measuring effective and ineffective erythropoiesis (Ricketts et al, 1975). We have used this method to investigate the balance between red-cell production and destruction in normal subjects and in patients with megaloblastic anaemia, iron deficiency anaemia, and refractory hypoplastic anaemia. The results show that the normal marrow can maintain an appropriate red-cell mass by altering red-cell production to match destruction. In the anaemias we have studied there is an increased rate of either intra- or extra-medullary red-cell destruction. The response of the marrow may be limited by iron supply, by defective nuclear maturation or by some intrinsic marrow defect.