Transfusion-Dependent Beta-Thalassemia - A Brief Review

Introduction:

Individuals with beta-thalassemia are incapable of producing enough protein called globin (an essential component) of the hemoglobin that is found inside red blood cells. Hemoglobin takes up oxygen in the lungs and transfers it to various parts of the body through the bloodstream.

Why Is Transfusion Required in Beta-Thalassemia Patients?

Blood transfusions are needed to treat anemia in people with beta-thalassemia. A blood transfusion is generally considered a safe procedure where blood is given to a patient through a tiny plastic tube inserted into one of the veins. A blood transfusion causes an increase in the hemoglobin level, which reduces the anemia and helps the patient feel better. Healthcare providers might advise the patient to take episodic transfusions when required or regular transfusions based on the overall health of the individual.

Although certain types of anemia are treated with iron supplements. However, taking iron supplements will not help people with beta-thalassemia as this type of anemia is not caused by a decreased amount of iron in the blood; it is caused by a reduction in red blood cells. Further, administration of iron supplements can harm a person with beta-thalassemia as the extra iron accumulates in the body and might cause damage to the organs.

What Happens When Hemoglobin Levels Are Low in People With Beta-Thalassemia?

If sufficient hemoglobin is not produced, less amount of red blood cells are seen in the bloodstream. Hence, less oxygen reaches the tissues and organs that require it, leading to a condition called anemia.

In children with beta-thalassemia, anemia might cause:

• Decrease in activity due to fatigue.

• Growth problems.

• Delayed puberty.

• Enlargement of the liver and spleen.

• Weakening of bones.

• Issues with concentration, memory, or learning new things.

In adults with beta-thalassemia, anemia might cause:

• Fatigue.

• Difficulty in performing daily activities.

• Bone weakening.

• An overactive spleen makes it difficult to filter old or damaged red blood cells.

• Fractures.

• Changes in quality of life.

• Trouble with concentration, memory, or learning new things.

These complications are seen as the bone marrow, a spongy substance in the middle of bones, becomes activated. The bone marrow gets expanded and tries to make up for the anemia by producing more red blood cells. These new cells also have decreased hemoglobin levels. When there is not enough hemoglobin, the body’s red blood cells do not function adequately, and they remain for a shorter period of time. This indicates that there is less number of healthy red blood cells in the bloodstream.

How Are Regular Transfusions for People With Beta-Thalassemia Initiated?

Blood hemoglobin levels are measured in grams per deciliter (g/dl). Doctors follow certain guidelines to decide whether to advise episodic or regular transfusions based on the type of thalassemia, hemoglobin levels, and observations related to a physical exam. Most patients with beta-thalassemia whose hemoglobin levels are below 7 g/dl can be recommended for regular transfusions. Regular transfusions are also essential, even if a person’s hemoglobin levels are greater than 7 g/dl if there are other complications, like:

• Growth problems.

• Delayed puberty.

• Bone deformities or fractures.

• Stroke.

• Blood clots.

• An enlarged spleen.

• High blood pressure (hypertension).

What Are the Components of a Transfusion Plan for People With Beta-Thalassemia?

Generally, the target pretransfusion hemoglobin level advised by the Thalassemia Western Consortium (TWC) for individuals with beta-thalassemia is

• 9.5 to 10.5 g/dL for patients with β thalassemia major.

• 9.0 to 10.0 g/dL for patients with HbE β thalassemia.

The maintenance of target pretransfusion hemoglobin levels has been determined earlier to make sure that there is normal growth, reduced fatigue, marrow hyperactivity, and suppression of splenomegaly in most patients with beta-thalassemia.

Usually, blood is transfused at the following rate:

• 200 to 300 ml/hour, based on tolerance, for adults.

• 5 ml/kg/hour for children.

The volume of blood transfused for individuals with beta-thalassemia major is as follows:

• 4 ml/kg per gram increase in hemoglobin, up to 20 ml/kg at a single visit for children.

• 2, 3, or 4 units per transfusion for adults.

The volume of blood transfused during a visit can be altered to maintain the target pretransfusion hemoglobin level.

The shortest time for a safe, complete transfusion might be different in different individuals.

Usually, people with beta-thalassemia require transfusions at the following frequency:

• Every three weeks for most adults with beta-thalassemia major.

• Every four weeks for children with beta-thalassemia major and most people with HbE beta-thalassemia.

The frequency of transfusions can be changed to maintain the target pretransfusion hemoglobin level. A reduced time interval between transfusions decreases hemoglobin level variability; however, it needs more frequent visits to the infusion center. An individual with beta-thalassemia undergoing a four-week transfusion schedule needs a greater volume of blood at each transfusion than an individual who is on a three-week transfusion schedule to attain the same target pretransfusion hemoglobin level.

What Are the Transfusion Considerations for People With Beta-Thalassemia?

Generally, it is considered essential to consider the following when making a transfusion plan for people with beta-thalassemia:

1. Individuals with an intact spleen might require more blood during their transfusions than those who have had a splenectomy.

2. Adults weighing above 132.28 pounds might require four units of blood at some visits.

3. Increased target pretransfusion hemoglobin levels or more frequent transfusions are required for the following patients:

• Congestive heart failure.

• Pulmonary hypertension.

• Symptomatic extramedullary hematopoietic masses.

• Severe fatigue.

• Bone pain in the pretransfusion period.

4. Individuals with congestive heart failure might also require a reduced transfusion volume and rate, depending on their cardiac function.

Conclusion:

Transfusion-dependent beta-thalassemia is a complex genetic disorder that demands ongoing medical care, emotional resilience, and the pursuit of innovative treatment solutions. While the burden is significant, advancements in gene therapy and other medical interventions offer newfound hope for individuals living with this condition. As research continues and medical science evolves, the ultimate goal remains the improvement of patient's quality of life and the realization of a future where the challenges of transfusion-dependent beta-thalassemia are overcome.

Beyond medical interventions, individuals with transfusion-dependent beta-thalassemia require comprehensive support to navigate the physical, emotional, and social challenges posed by the condition. Multidisciplinary care teams, including hematologists, genetic counselors, psychologists, and social workers, play a crucial role in addressing the diverse needs of patients and their families.