Systematic transfusions are lifesaving for patients with severe congenital anemias, but they eventually lead to iron overload and the indispensable necessity of iron chelation therapy. Current official guidelines for the starting time of chelation therapy derives from data obtained with the use of desferrioxamine, which has been shown to have significant toxicity in very young patients, especially when used in low iron burden. No data exist on the use of the oral iron chelators in this setting. The purpose of this study was to evaluate the changes of iron parameters at the initial period of transfusion therapy in newly diagnosed patients with congenital anemias
Nine patients participated in this study. One patient was diagnosed with Diamond-Blackfan anemia, one patient with severe alpha-thalassemia, while 7 had beta-thalassemia. Three of the beta-thalassemia started transfusions at 1.5, 2 and 5 years, respectively. All others started transfusions between 2-4 months of age. Iron, transferrin saturation, ferritin levels. serum transferrin receptors (sTfR), were estimated by standard methods, while labile plasma iron (LPI) by the FeROS LPI kit (Aferrix, Ltd, Israel). The main results of the study show that: 1) transferrin saturation increases rapidly with transfusions (mean levels after 4 transfusions 49.2% (range: 23.8-90.5%), mean after 6 transfusions 69.1% (range: 39.5-112%)), though it has significant diversity in between patients, as indicated also by one patient that continued to have transferrin saturation at 65% even after 12 sessions. Transferrin saturation significantly correlates with ferritin levels (r=0.763, p<0.0001), with the number of previous transfusions (r=0.486, p=0.002) and with the levels of sTfR, which is also an index of the degree of erythropoiesis (r=0.550, p<0.001). The increase of ferritin correlates also with the sTfR levels (r=0.697, p<0.0001), while the rate of increasing transferrin saturation per transfusion correlates to sTfR levels (r=0.486, p=0.002). LPI levels appears early in the transfusion history and correlates with transfusion saturation.
The results of the study indicate that iron overload starts early in the transfusion history of young patients with transfusion-dependent anemias. These findings dispute current guidelines suggesting starting chelation therapy, when the patients have already received 10 transfusions or when ferritin levels reach more than 1000ug/dl.
No relevant conflicts of interest to declare.
