From the Guidelines
Exchange transfusion does not increase iron overload; instead, it helps reduce it by removing excess iron from the body. This is because during an exchange transfusion, a patient's blood is removed and replaced with donor blood, effectively removing excess iron 1. In contrast to simple transfusions, where blood is added without removing any, exchange transfusions do not contribute to iron accumulation. Simple transfusions can lead to iron overload because each unit of transfused red blood cells contains approximately 200-250 mg of iron that the body cannot naturally eliminate.
According to the American Society of Hematology 2020 guidelines for sickle cell disease, regular red cell transfusions lead to iron accumulation in the liver, heart, and endocrine organs 1. However, exchange transfusions are a different process, and their effect on iron levels is distinct. The guidelines discuss the importance of monitoring iron burden over time, using methods such as serum ferritin level tests and noninvasive MRI techniques 1.
Key points to consider:
- Exchange transfusions remove excess iron from the body, reducing the risk of iron overload.
- Simple transfusions can contribute to iron accumulation due to the iron content in transfused red blood cells.
- Monitoring iron burden is crucial in patients receiving regular transfusions, and exchange transfusions can be part of an effective iron management strategy.
- Iron chelation therapy is often used alongside exchange transfusions to manage iron levels in chronically transfused patients.
From the Research
Exchange Transfusion and Iron Overload
- Exchange transfusion is a medical treatment in which a patient's red blood cells are replaced with donor red blood cells, and it is often used to manage conditions such as sickle cell disease and thalassemia.
- The relationship between exchange transfusion and iron overload is complex, and research suggests that repeated blood transfusions, including exchange transfusions, can lead to iron overload in patients 2, 3.
- Iron overload occurs when the body accumulates excess iron, which can cause damage to organs such as the liver and heart, and can increase the risk of morbidity and mortality 4, 5.
- Studies have shown that patients who receive regular blood transfusions, including exchange transfusions, are at risk of developing iron overload, and that iron chelation therapy can help to reduce this risk 2, 6.
Mechanisms of Iron Overload
- The mechanisms of iron overload in patients who receive exchange transfusions are not fully understood, but research suggests that they involve the accumulation of iron from transfused red blood cells, as well as increased intestinal iron absorption due to ineffective erythropoiesis and hepcidin suppression 2, 6.
- The rate and extent of iron accumulation can vary depending on the underlying condition, the frequency and volume of transfusions, and individual patient factors 3, 6.
Monitoring and Management of Iron Overload
- Regular monitoring of serum ferritin levels and non-invasive imaging techniques, such as MRI, can help to diagnose and quantify iron overload in patients who receive exchange transfusions 2, 6.
- Iron chelation therapy, using agents such as deferoxamine, deferiprone, and deferasirox, can help to reduce iron overload and prevent complications, and the choice of therapy depends on individual patient factors and the extent of iron overload 4, 5.