Beta thalassemia is a preventable blood disease that is inherited from parents to children. a significant public health issue in Turkey in Mediterranean countries, where there is also a problem.Although detection of carriers, genetic counseling and preventable diagnosis are preventable, at least 365,000 thalassemia patients are born and treated in the world every year. approximately 1,300,000 thalassemia carriers in Turkey and has 4,500 thalassemia patients.
Beta thalassemia disease is a disease that decreases the life expectancy significantly and negatively affects the quality of life. Treatment of the disease is difficult and the cost is very high. The annual treatment cost of a thalassemia patient is around $ 10,000. Therefore, it is very important to prevent the emergence of diseased individuals and the necessary protective measures are supported by the state.
How does beta thalassemia occur?
Hemoglobin contained in red blood cells in our blood carries the oxygen necessary for tissues. The hemoglobin molecule has two parts, both globulin and globulin. In a healthy person, the globin protein consists of two double polypeptide chains. According to the polypeptide chains, there are 3 different types of hemoglobin in an adult’s erythrocytes:
1. Hemoglobin A: Globin fragment is made of 2 alpha, 2 beta polypeptide chain. It contains 96-98% of total hemoglobin.
2. Hemoglobin F: Globin fragment is made of 2 alpha and 2 gamma polypeptide chains; it contains less than 1% of total hemoglobin.
3. Hemoglobin A2: The Globin fragment is made up of 2 alpha and 2 delta polypeptide chains and contains less than 2-3% of total hemoglobin.
Hemoglobin production is under the control of genes, and if a deficiency or disorder occurs in the production of one of the globin chains that make up the hemoglobin as a result of a familial genetic defect, thalassemia occurs. Whichever of the Globin chains cannot be synthesized or if the synthesis of which is reduced, the thalassemia is called with its name. For example, the change in beta globin synthesis leads to beta thalassemia and changes in alpha globin synthesis cause alpha thalassemia.As a result of the hemoglobin structure defect in beta thalassemia, red blood cells are rapidly destroyed, resulting in anemia, ie anemia.
What is carrier and disease in beta-thalassemia?
In humans, one of the genes belonging to one property is found, one from the mother and the other from the father. For the beta thalassemia, if the globin gene from the mother and father are normal, the child is normal, if the child has changed, the child becomes ill and the child becomes ill.
How does beta thalassemia show familial transition?
A beta thalassemia carrier is likely to be 50% carrier for each child to be born if it marries a normal non-carrier, and 50% is normal. In this case, the disease does not occur, there is nothing to fear;however, it is investigated whether there are carriers in children. The carrier is given the necessary information to be healthy children in the future, if the carrier is married to a child may be told that the disease.
The higher the rate of carriage in a population, the more likely it is that the two carriers are likely to have marriage and sick children. As a result of the marriage of two carriers, there is a 25% chance of being born with a disease, 50% being a carrier and 25% being born normal for each child. Especially in consanguineous marriages, the risk of having a diseased child is high and it is very important for them to have the necessary examinations before marriage.
What is beta thalassemia trait in Turkey and did vary by region?
The prevalence of beta thalassemia in Turkey is around 2,1%. This number increases in different regions and the frequency of carrier increases up to 13% (Antalya 13%, Edirne 6.4%, Urfa 6.4%, Aydın 5.1%, Antakya 4.6%, İzmir 4.8%, Muğla 4.5%, Istanbul 4.5%). The regions of the Mediterranean, Aegean and Thrace regions are high.
How is thalassemia carriage and disease detected?
In families known to be patients or carriers, the diagnosis is made in children who are brought for screening or anemia. The carriers are slightly bloodless, they do not benefit from iron therapy.Diagnosis is easily made by evaluating the complete blood count and performing hemoglobin electrophoresis. There are severe anemia in patients; Complete blood count, hemoglobin electrophoresis and genetic tests are performed to determine the exact diagnosis of the mother, father and child.
What are the clinical forms of beta thalassemia?
Beta thalassemia is clinically seen in 4 ways:
1. Thalassemia major: The mother and father are carriers, and the two globin genes that are passed on to the child are defective. Generally, when the baby is 6 months, a severe anemia occurs and the diagnosis is made in the first 4-12 months of life. Fatigue, pallor, anorexia, restlessness, liver, spleen growth as a result of abdominal distension, expansion and thinning of the bones, nasal root flatness, forehead and other facial bones in the face of the abnormal face appear. The mean erythrocyte volume and mean erythrocyte hemoglobin levels were decreased in laboratory tests; has a severe anemia. The hemoglobin level is below 7 g / dl. Hemoglobin A is almost absent in hemoglobin electrophoresis and replaced by hemoglobin F. Hemoglobin A2 may be normal, low or slightly increased. These patients must receive regular treatment throughout their lives.
The appearance of erythrocytes in the peripheral blood smear of a patient with beta thalassemia major 2. The thalassemia intermedia: The mother and the father are carriers, the two beta globin genes that are passed on to the child are defective, but the difference in thalassemia major is of a type that leads to a lighter clinical picture. The clinic is more moderate, anemia is lighter. The hemoglobin level is between 7-10 g / dl. Patients generally do not require regular blood transfusion.
3. Thalassemia minor (Thalassemia carrier): These people have no problems other than mild anemia.In laboratory tests, the hemoglobin value was slightly lower, mean erythrocyte volume and mean erythrocyte hemoglobin levels decreased. Unlike iron deficiency, erythrocyte counts were normal or increased. Hemoglobin A2 and hemoglobin F are slightly elevated in hemoglobin electrophoresis.Thalassemia carriage is not a disease and does not require treatment. In thalassemia carriers, iron deficiency may develop in infancy due to poor nutrition. Therefore, patients diagnosed with iron deficiency should be evaluated after iron therapy and thalassemia carrier should not be omitted.
4. Thalassemia minima: (Thalassemia trait): Findings are as in thalassemia minor, but hemoglobin electrophoresis is normal, diagnosis is made by gene analysis.
What is the treatment and follow-up of a patient with beta thalassemia?
The patient with beta thalassemia needs blood support every 3-4 weeks for life. The hemoglobin of the thalassemia patient should be kept above 9.5 g / dl. Blood transfusions to correct anemia lead to an accumulation of iron in the body and cause cell damage in organs such as the heart, liver, thyroid, pancreas and spleen. Patients develop problems such as heart failure, diabetes, developmental retardation and hormonal insufficiency. To prevent the development of iron, a drug (desferrioxamine) is given to patients with a subcutaneous infusion that lasts at least 5 days of the week and 8-12 hours with a special pump, usually around 3 years of age. In recent years, oral medications have also been used in patients who are considered suitable by the physician.
In patients with thalassemia, complete blood count, blood iron level, heart, liver and hormonal system are evaluated regularly; attention to the diseases transmitted by blood. If the annual blood consumption exceeds 1.5 times normal, spleen is removed in advanced age. Removal of the spleen reduces the need for blood, but it is not a definitive solution.
Bone marrow transplantation is a treatment that can completely correct the disease. The bone marrow transplantation of tissue type-fit healthy siblings is successful in patients who are especially well-treated and do not have any damage to the liver. However, in some cases, various serious problems may occur during or after bone marrow transplantation or transplantation fails.
Gene transplantation is still not applied to patients.
What should nutrition be in patients with beta thalassemia?
In addition to iron accumulation through the blood donated in these individuals, the amount of iron absorbed from the intestine increases and therefore the feeding of iron-rich foods should be avoided.However, this does not apply to thalassemia carriers; Iron deficiency anemia may also develop in cases where the need for thalassemia carriers increases.
Can beta thalassemia patients get married and have children?
Patients who receive treatment for regular blood transfusion and iron accumulation can get married and have children. A person with beta thalassemia who is not a carrier, a normal person to marry the child becomes a carrier, no patient; if the child is married to a carrier, there is a 50% patient and 50% carrier for each child.
How to prevent beta thalassemia?
- Community education: The society should be trained in beta thalassemia and informed about the risks of consanguineous marriages.
- Determination of Carriers: It is very important that all relatives of patients and carriers should be screened by a blood test and the couples to be married should be evaluated in terms of carriage.
- Genetic counseling: If spouses are both carriers, spouses should be consulted, referred to genetic diagnosis centers, and necessary examinations should be completed prior to pregnancy (sample mutation analysis).
- Prenatal diagnosis: If the marriage of the two carriers is in question, couples must consult a doctor at the early stage of each pregnancy (first 2 months) and have the necessary examinations performed.