What Is Thalassaemia?

Introduction

Thalassaemia is an inherited blood disorder characterised by low production of haemoglobin, which is an essential protein contained in red blood cells. Thalassaemia can be cured and treated with proper therapy such as chelation therapy, blood transfusion, and healthy life maintenance (regular exercise, healthy diet).

Haemoglobin is important in making up red blood cells. Without haemoglobin, the lifespan of red blood cells is reduced and they start dying prematurely (before they are destined to die). This causes a decrease in the amount of red blood cells in the blood. As red blood cells are involved in carrying oxygen through the blood, reduced red blood cells can lead to reduced oxygen reaching the body organs, which can lead to a person feeling weak, tired or short of breath, which are the symptoms of anaemia. Thalassaemia affects around 4.4 out of 10,000 births all over the world.¹

Thalassaemia has two types depending upon the part of haemoglobin that is affected. These are alpha thalassaemia and beta thalassaemia.

What are the symptoms of thalassaemia?

The symptoms of thalassaemia occur as a result of a deficiency of oxygen. You may not have any symptoms in the case of mild anaemia associated with thalassaemia. Although signs and symptoms of thalassaemia vary according to the severity as well as type of thalassaemia, common signs and symptoms include the following:²

• Fatigue
• Dizziness
• Weakness
• Shortness of breath
• Paleness
• Dark urine
• Abdominal swelling
• Deformities in the facial bones
• Slowed growth

To treat thalassaemia, blood transfusions are carried out. As a result of these blood transfusions, there may be too much iron in the body which leads to heart and liver diseases. Heart diseases such as arrhythmias, heart attacks, and heart failure are major complications associated with thalassaemia. Other complications of thalassaemia include infection and osteoporosis (fragile bones).³

What causes thalassaemia?

Thalassaemia is caused by defective genes that are responsible for making one of the two proteins of haemoglobin. Haemoglobin is composed of these proteins:³

• Two alpha globin proteins
• Two beta globin proteins

In thalassaemia, genes that are responsible for the production of one of these two proteins get defective. As a result, thalassaemia has the following two types:

• Alpha thalassaemia
• Beta thalassaemia

If the genes which control the production of the alpha globin protein of haemoglobin are altered or missing, alpha thalassaemia results. In the case of a defect in the gene responsible for the beta globin protein, beta thalassaemia occurs. These two types can further be categorised into:

• Thalassaemia major
• Thalassaemia minor

In thalassaemia major, the affected person receives the faulty gene from both parents, while in thalassaemia minor, the patient acquires the defective gene from only one parent. People with thalassaemia minor do not usually show any symptoms and are said to be carriers of the disease. Carriers of thalassaemia do not develop symptoms but pass the disease on to their offspring (through the defective gene).

Who is at the most risk of thalassaemia?

Risk factors of thalassaemia include the following two factors:⁴

Family history

Thalassaemia is an inherited blood disorder, meaning the disease is passed onto children from their parents. If you possess an altered or missing haemoglobin-synthesising gene, your children may have thalassaemia.

Ancestry

Thalassaemias are more prevalent in people of the following origins:

• Greek
• Italian
• Middle Eastern
• African
• Southern Asian

What are the complications of thalassaemia?

Complications of thalassaemia are associated with moderate to severe forms of thalassaemia. These complications are:⁴

Iron overload

Too much iron (iron overload) may occur either due to the disease or excessive blood transfusions. This iron overload can damage the liver, heart and hormone-producing glands. Heart diseases may occur such as cardiac arrhythmias (irregular heartbeat), heart attack, and heart failure.

Infection

People with thalassaemias are vulnerable to developing infections, particularly if they have had their spleen taken out.

Osteoporosis 

Bone marrow may expand in people with thalassaemia, resulting in deformities, particularly in the facial bones. This expansion also causes the bones to become brittle and weak, leading to osteoporosis.

How is thalassaemia diagnosed?

Thalassaemia can be diagnosed during pregnancy or immediately after the baby is born. Blood tests can be done to check whether you are a thalassaemia carrier or not.⁵ 

Screening during pregnancy

Diagnosing thalassaemia during pregnancy may also be known as prenatal (before birth) screening. The following tests are conducted to diagnose thalassaemias in the foetus:⁶

Amniocentesis: During this test, a sample of the fluid covering the foetus is taken and tests are performed on it. Amniocentesis is carried out at about the 16th week of pregnancy.

Chorionic villus sampling: This test is performed at 10 to 13 weeks of pregnancy and is done on a small piece of placental tissue.

Newborn screening

Testing for thalassaemia after birth is not routinely carried out. However, a common type of thalassaemia, beta thalassaemia major, is generally detected through the heel prick test. During this test, the newborn baby’s heel is pricked to get a small blood sample. This sample is then analysed to discover if your baby has thalassaemia.⁶

Blood tests may be performed at any time point throughout life to check for the presence of thalassaemia. 

Testing for the thalassaemia trait

Having the thalassaemia trait means that you carry the defective or faulty genes that are responsible for causing thalassaemia, but do not necessarily have the disease.

If you have the thalassaemia trait, there are chances that your child may have thalassaemia. Thalassaemia trait is detected through blood tests that can be carried out at any point in your life. A complete blood count (CBC) is done to measure the amount of haemoglobin and red blood cells. In thalassaemia, both haemoglobin and red blood cells are reduced in number.

This test can be especially helpful if you have a family history of thalassaemia, or a partner who is a carrier of the thalassaemia gene.⁷

How is thalassaemia treated?

The most frequently used therapies for thalassaemia are: regular blood transfusions, folate supplementations, and iron chelation therapy.⁸

Blood transfusion

In cases of moderate or severe forms of thalassaemia, blood transfusions are a standard means of treatment. During this procedure, you receive healthy blood through an intravenous (IV) line that is inserted into one of your blood vessels via a needle. 

As red blood cells die after 120 days, you will require frequent blood transfusions to keep up the reserves of healthy red blood cells. These regular transfusions may result in iron overload that damages the heart, liver and hormone-producing glands. In order to prevent this damage, iron chelation therapy is employed following the transfusion.

Iron chelation therapy

Iron chelation therapy is utilised to remove excess amounts of iron from your blood. Iron levels may rise as a result of thalassaemia or due to frequent blood transfusions. As this excess iron is extremely damaging to your heart, liver and other organs, removing it from the blood is crucial.

Oral (by mouth) as well as intravenous medications are administered for iron chelation. These medications may include deferasirox, deferiprone, or deferoxamine.

Stem cell transplant

Stem cells are the cells found inside the bones and are responsible for the production of blood cells, including red blood cells. This treatment is also known as a bone marrow transplant. During stem cell transplant therapy, the faulty stem cells of thalassaemia patients are replaced with stem cells from a healthy person (stem cell donor). 

Stem cell transplant is the only therapy that can cure thalassaemia. However, it is a high-risk procedure, and finding a donor is also incredibly challenging.

Summary

Thalassaemia is an inherited blood disorder and is passed on from parents to children. Although it cannot be prevented, it can be managed through regular blood transfusions and iron chelation therapy. You are more likely to have thalassaemia if you have a family history of the disease, or if you are from the thalassaemia-prevalent regions such as Greece, the Middle East, or South Asia. If you or your spouse have a family history of thalassaemia, then you may carry the thalassaemia gene which increases the risk of your child developing the disease. Therefore, it is wise to get tested if you are planning on having children. 

FAQs

Can thalassaemia be cured?

Thalassaemia can be cured through stem cell transplant which is done quite rarely as it is a high-risk procedure, and finding a donor is also a difficult task.

How is thalassaemia inherited?

Thalassaemia is inherited only if both of your parents have the thalassaemia gene. If only one of the parents has this gene, then you may be a carrier of thalassaemia.

How do I know if I have thalassaemia?

Knowledge of a family history of thalassaemia is very important if you want to know your chances of having the disease. If you have the  above-mentioned symptoms of thalassaemia, and also a family history of the disease, consult with your physician. Generally, blood tests are carried out to diagnose this disease.

Can I prevent thalassaemia?

No. As thalassaemia is an inherited disorder (passed onto children from parents), it is not possible to prevent it. If you or your partner have a family member with thalassaemia, or if both of you have family members from a thalassaemia-prevalent area, then you should get tested for the disease. This knowledge may help you if you are planning to conceive.

Can thalassaemia patients have children?

Yes, women with thalassaemia can have children. However, there may be increased chances of the child developing this disease, especially if your spouse is a thalassaemia carrier. This should be discussed with the physician if you are planning on having children.