Thalassemia is an inherited blood disorder in which a person suffers from anemia as a result of decreased production as well as rapid destruction of the red blood cells (RBCs). India carries a huge burden of this disease with more than 10,000 thalassemic children born every year. Statistically about 3.4% of Indian population suffers from thalassemia. According to hematology experts, this condition can largely be prevented with increased awareness. Here is all you need to know about the condition.
Overall there are two kinds of thalassemia, alpha and beta. The form more commonly seen in India in beta-thalassemia. Alpha thalassemia is seen more in people of Chinese and African origin.
Depending on the inherited pattern, the condition can present in two major forms: Thalassemia major and thalassemia minor.
Thalassemia minor: In case the defective gene is inherited from either of the parents the child will be thalassemia minor.
Thalassemia major:If the defective gene is inherited from both the parents then the child will be thalassemia major, a severe form of thalassemia.
Thalassemia is a genetic condition. There are specific genes that code for hemoglobin, the protein in RBCs responsible for carrying oxygen throughout the body. There are separate genes coding for alpha and beta chains that are self-arranged to form a hemoglobin molecule. Defects in either of the genes can result in the production of abnormal hemoglobin which causes RBC destruction.
You may inherit this defective gene either from your mother or your father or from both.
Thalassemia minor:Those who have inherited the defective gene for alpha chain of hemoglobin usually do not show any symptoms. That’s because the alpha gene defect does not cause any major problem that interferes with the hemoglobin function. But people who have a defective beta chain of hemoglobin have mild anemia. These people are usually healthy fully functional with a normal lifespan. There haemoglobin can range from completely normal to 1-2 gm/dL less than normal. The only way to know that someone is thalassemia minor is by a blood test.
Thalassemia major: People who have inherited the defect for beta chain of hemoglobin from both the parents suffer from thalassemia major, also called hemoglobin H disease or Cooley’s anemia. The symptoms are severe and usually seen within the first 2 years of life. They include:
- Severe anemia
- A pale and listless appearance
- Loss of appetite
- Delayed growth and puberty
- Enlargement of the spleen, liver and heart
- Weak bones
Severe thalassemia is diagnosed early in childhood because the signs develop within the first two years of life. A Milder form of thalassemia is diagnosed with a complete blood count and haemoglobin test.
- A complete blood count (CBC) can raise suspicion of thalassemia
- A microscopic analysis helps identify abnormal RBCs that appear smaller in size
- A test called haemoglobin electrophoresis is used to confirm the diagnosis and to identify whether the patient has alpha or beta thalassemia
- Mutational analysis can be done when results of hemoglobin electrophoresis are inconclusive
Treatment depends on the form of condition the patient suffers from. Currently, it is treated with regular blood transfusions and chelation therapy.
Blood transfusion: Blood transfusion is the main treatment given to patients with major thalassemia. Transfusion is required every 2-3 weeks to supplement RBCs and maintain a haemoglobin level of around 9gm/dL. Here' are 10 facts you must know about blood transfusion.
Iron chelation therapy: With repeated blood transfusions, the iron load of the body in thalassemic patients increases. This condition is called iron overload which can create complications and damage other healthy organs including the heart and liver. To prevent iron overload, medicines are prescribed. Deferoxamine and Deferasirox are common iron-chelators that bind free iron in the blood and cause its elimination through urine.
Supplements: Folic acid supplements must be given to enhance the production of healthy RBCs.
Are there any advanced treatment options available?
Stem cell or Bone Marrow transplant is the only curative option for thalassemia major at this time. Stem cells are the precursors of RBCs present in the bone marrow. In thalassemic patients, the stem cells themselves carry the defect causing production of abnormal RBCs. But when bone marrow cells from a healthy donor are transplanted into the patient to replace those faulty stem cells they can make their own healthy RBCs. This treatment has been carried out successfullyfor thousands of children with thalassemia in India and worldwide. The best potential donor is a brother or sister. A special genetic test called HLA is done to identify genetic match. The possibility of any one sibling of being a complete match. Other means of finding a match is by voluntary donor registries. Most recently a technique called haploidentocal or half match transplant has been developed. This allows parents to be potential donors as well offering this curative therapy to more and more children.
Several studies are now exploring other possibilities to find a cure for thalassemia. One of the approaches involves insertion of normal gene in stem cells of the bone marrow of the patients. With the normal gene, the bone marrow cells will be able to produce their own healthy red blood cells with normal hemoglobin.
It is a genetic condition so it can be prevented only in future generations. People who are living with mild thalassemia can prevent their children from carrying the defect with the help of genetic screening. In fact, such individuals should definitely have their partners screened before getting married. Here are 5 reasons you should get screened for thalassemia before getting married.
The content has been verified by
Dr VP Choudhry, Senior Consultant, Haematology, Fortis Healthcare.