DISTRIBUTED MODEL OF IRON KINETICS FOR CLINICAL-ASSESSMENT OF NORMAL-ABNORMAL ERYTHROPOIETIC ACTIVITY

The use of mathematical models of iron metabolism has been recognized as an essential tool for analyzing ferrokinetic data. Multicompartment models, however, did not make it possible to describe marrow iron kinetics, taking into account that marrow erythroid cells uptake iron from the plasma according to their maturity. In this paper, a distributed model for marrow iron kinetics is presented which considers two different marrow iron pools: the nonhem and the hem iron pool. To each pool, an iron density function is assigned which is assumed to be a function of both maturity of the erythroid cells and time. Moreover, the model includes pathways to account for the loss of nonhem and hem iron before red cell dismission from the bone marrow. Model parameters were estimated fitting experimental data obtained by measuring the radioactivity in the plasma and in red cells after an intravenous injection of transferrin-bound 59Fe. Thereafter, some parameters useful for clinical purposes, such as effective and ineffective erythropoiesis, maturation time of erythroid cells, and mean red cell life span, were evaluated. Results obtained in normal subjects and anemic patients are presented. Copyright © 1979 by The Institute of Electrical and Electronics Engineers, Inc.