Laboratory medicine and iron overload: diagnostic and therapeutic aspects

Abstract

: The laboratory input is essential for the diagnosis and treatment of systemic iron overload which may be acquired (transfusions, parenteral iron supplementation) or genetic (hemochromatosis). From the diagnostic standpoint, besides clinical examination, the combination of plasma transferrin saturation and ferritinemia, provided they are rigorously interpreted, forms the usual bipodal biochemical basis for suggesting the existence of iron excess, but also its mechanism, and its severity. This duo must lead to subsequent direct evaluation of body iron load by assessing liver iron concentration (LIC). This determination is based primarily on magnetic resonance imaging (MRI) that, given its absence of invasiveness, has largely replaced the biochemical evaluation of the iron content of a liver biopsy sample. Furthermore, the decision for performing genetic testing, and for selecting the appropriate genetic tests, is guided by the biological data, together with the clinical and imaging context. From the therapeutic standpoint, plasma transferrin saturation and ferritin levels are critical for starting and following the treatments that are dominated by oral chelation or phlebotomies depending on whether anemia is present or not. Evaluating plasma non-transferrin bound iron (NTBI) and hepcidinemia remains in the field of clinical research.