Chapter 4: Iron Overload

Because humans lack a natural physiological mechanism to excrete surplus iron, the condition arises either through genetic predispositions that increase intestinal absorption or as a side effect of life-saving chronic blood transfusions for severe anaemias. Hereditary haemochromatosis is the primary genetic form discussed, often caused by mutations in the HFE gene that disrupt the hepcidin-ferroportin regulatory axis, leading to uncontrolled iron uptake into parenchymal cells. Secondary iron overload frequently impacts individuals with thalassaemia major or myelodysplastic syndromes, where each unit of transfused blood contributes significantly to the body’s iron burden. If left untreated, the metal deposits in vital organs—most notably the liver, heart, and endocrine system—triggering severe complications such as cirrhosis, cardiac arrhythmias, diabetes mellitus, and growth failure. Assessment of iron status relies on laboratory markers like serum ferritin and transferrin saturation, supplemented by advanced T2* magnetic resonance imaging, which serves as the most reliable non-invasive method for quantifying iron in the heart and liver. Treatment protocols are tailored to the underlying cause: genetic disorders are typically managed through regular phlebotomy or venesection to deplete iron stores, whereas transfusional overload necessitates iron chelation therapy using pharmacological agents such as deferoxamine, deferiprone, and deferasirox. Through early detection and modern therapeutic interventions, medical professionals can significantly mitigate organ damage and enhance the quality of life and life expectancy for haematology patients.