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Why might people with thalassemia need repeated blood transfusions?

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blood disease Peripheral blood smear revealing histopathologic features indicative of a blast crisis in a case of chronic myelogenous leukemia (CML). Blast crisis occurs when one-fifth to one-third of the cells in the blood or bone marrow are immature blood cells, or blast cells. This phase of CML is characterized by fever, weakness, and an enlarged spleen.

People with thalassemia major require repeated blood transfusions primarily to manage severe anemia.21

In this condition, genetic mutations lead to a deficiency in the production of globin polypeptide chains, which causes an imbalance in hemoglobin synthesis. This results in the ineffective production of red blood cells and the destruction of existing red cells (hemolysis). Because the body's genetically defective red cell precursors are unable to produce enough mature, functional red blood cells to transport oxygen to tissues, patients suffer from chronic, severe anemia.21

While transfusions provide necessary red blood cells, they are only a temporary measure because the transfused cells eventually break down, leading to an accumulation of excessive iron in the body's tissues. Additionally, the spleen may become enlarged and further worsen the anemia by trapping and pooling circulating red blood cells.21