Thalassemia – why does the disease develop? Forms, symptoms and treatment of thalassemia

Proven content

Thalassemia (thyroid cell anemia) is an inherited condition with a characteristic anemia that can lead to a child’s underdevelopment. The disease is genetically determined, and in its course there is an excessive breakdown of erythrocytes. This may be due to the abnormal production of hemoglobin chains.

Thalassemia – what is the disease?

Thalassemia is a congenital disease – one with which we are born and the formation of which we have no control over, is otherwise known as thyroid cell anemia. It is caused by the abnormal formation of hemoglobin chains – a protein that plays a very important role in our body. Hemoglobin is found in red blood cells (erythrocytes) and, thanks to its structure, carries oxygen. There are two types of disorders in the structure of hemoglobin that disrupt its function: thalassemia and sickle cell anemia (both have a genetic basis, i.e. they can be inherited from generation to generation). By delivering it to cells, it enables their proper functioning. Thalassemia is a condition that is inherited autosomal recessively, regardless of gender, because the genes responsible for producing hemoglobin are located outside the sex chromosomes.

It is the improper structure of hemoglobin that causes its oxygen-carrying properties to be impaired. Then there is hypoxia, which the body wants to exclude by further production of red blood cells in the marrow. On the other hand, the spleen responsible for the destruction of blood cells recognizes them as damaged and causes them to break down (hemolysis). As a consequence, small and poorly colored blood cells are formed which transport less oxygen. Hemoglobin is a protein found in red blood cells and is responsible for the red color of blood. Due to its biochemical properties, it has the ability to carry oxygen.

The disease is most common in the regions of Africa, Asia and the Mediterranean.

Thalassemia – Why does the disease develop?

Hemoglobin synthesis is genetically determined. There are genes that contain information about the structure of the hemoglobin molecule.

Hemoglobin is made up of heme and an envelope – called globin polypeptide chains. In a normal molecule, there are 4 such chains which, like ribbons, wrap around the heme grain. The globin chains have different designations: α, ß, γ and б. In the red blood cells of an adult there are 3 types of hemoglobin, differing in the configuration of the chains that make up them. HbA accounts for the most, over 97%.

The cause of thalassemia is an error in the information stored in genes about the structure of hemoglobin molecules. The effect is to reduce the synthesis of individual chains of this protein. If it concerns α chains, we can talk about thalassemia alpha, and in the case of ß chains – o beta thalassemia. The latter form of the disease is more common.

Thalassemia and symptoms

The impaired structure of hemoglobin causes red blood cells to be smaller, less red and transport less oxygen. As defective, they are destroyed in the bone marrow and in the spleen. This can in turn lead to enlargement of the spleen and the development of jaundice. In addition, anemia is associated with insufficient tissue oxygenation. This can manifest as weakness and easy fatigue, pallor, impaired concentration and attention, headache and dizziness, increased heart rate. Signs of alpha thalassemia may appear in utero in the form of fetal edema.

Other symptoms of thalassemia are:

1. greater susceptibility to infections,
2. chest pain and shortness of breath (feeling of lack of air)
3. skin ulcers,
4. facial bone deformities,
5. bone marrow hypertrophy leading to bone deformation and an increased predisposition to pathological fractures.

Important! Treatment of thalassemia with blood transfusions can lead to infertility, diabetes, and hypothyroidism and parathyroidism.

Thalassemia and its characters

There are three types of thalassemia disease based on the severity of its course.

1. Thalassemia minor – it is the mildest form of the disease in the course of which there is a minimal deficiency of the β chain; there is a slight anemia that does not require specific treatment.

2. Thalassemia intermedia – is a moderate (medium) form of the disease. Sometimes blood transfusions are necessary to improve the patient’s quality of life, although it is not necessary to keep the patient alive.

3. Thalassemia major – is the most severe form of the disease, the symptoms of which usually appear around the age of two. They are very heavy and often a blood transfusion is needed to save the patient’s life.

Diagnosis and treatment of thalassemia

The diagnosis of this condition can be very difficult as it is easily confused with iron deficiency anemia. Often the first step in diagnosing a disease is enlarging the spleen. Due to diagnostic difficulties, the doctor orders a number of tests, including:

1. blood count (checking the shape of red blood cells, which is abnormal in thalassemia),
2. x-ray of the bones,
3. assessment of iron levels in the body,
4. hemoglobin electrophoresis (a test to detect an abnormal form of hemoglobin),
5. a biopsy or sampling of a bone marrow fragment.

Severe anemia is treated with regular red blood cell transfusions. As a result, it is possible to stop the production of defective blood cells and prevent bone growth and cardiac abnormalities. It is worth mentioning that each blood transfusion causes the body to receive a large amount of iron, which the body cannot cope with. As a consequence, iron builds up in various tissues, damaging them in the process. Sometimes splenectomy, i.e. removal of the spleen, is required. This treatment reduces the number of blood cells destroyed in the spleen.

The prognosis depends on the type of thalassemia. In the case of generalized fetal edema, the disease is usually fatal (before or after delivery). In contrast, patients with mild thalassemia usually function normally.

Does thalassemia affect a child’s development?

Symptomatic and severe thalassemia may result in impaired child development and a number of anemia-related complications (e.g. abnormal heart function). Beta thalassemia major may be associated with onset hemosiderosis. This is a state of excessive iron build-up in various tissues that can impair their function.

Thalassemia – can this disease be prevented?

Thalassemia disease cannot be prevented because it is a genetically inherited disease.

Text: lek. med. Matylda Mazur

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