Transfusion regimens in thalassemia intermedia

Abstract

Thalassemia intermedia (TI) is a heterogeneous disease, in terms of both clinical manifestations and underlying molecular defects. Some TI patients are asymptomatic until adult life, whereas others are symptomatic from early childhood. In contrast with patients with Thalassemia major (TM), the severity of anemia is less and the patients do not require transfusions during at least the first few years of life. Many patients with TI, especially older ones, have been exposed to the multiple long-term effects of chronic anemia and tissue hypoxia and their compensatory reactions, including enhanced erythropoiesis and increased iron absorption. Bone marrow expansion and extramedullary hematopoiesis lead to bone deformities and liver and spleen enlargement. Therapeutic strategies in TI are not clear and different criteria are used to decide the initiation of transfusion and chelation therapy, modulation of fetal hemoglobin production, and hematopoietic stem cell transplantation on an individual basis. The clinical picture of well-treated TM patients with regular transfusionchelation therapy is better from TI patients who have not received adequate transfusion therapy. There is a significant role of early blood transfusion to prevent and treat complications commonly associated with TI, such as extramedullary erythropoiesis and bone deformities, autoimmune hemolytic anemia, leg ulcers, gallstones, pseudoxantoma elasticum, hyperuricosuria, gout and pulmonary hypertension, which are rarely seen in thalassemia major. Nowadays, indications of transfusion in patients with TI are chronic anemia (Hb < 7 g/ dL), bone deformities, growth failure, extramedullary erythropoiesis, heart failure, pregnancy and preparation for surgical procedures.