Beta Thalassemia (Gene Promoter Involvement)

Definition

Definition of Beta Thalassemia (Gene Promoter Involvement)
Beta-thalassemia (ß-thalassemia) is characterized by reduced synthesis of the hemoglobin subunit beta (hemoglobin beta chain) that results in microcytic hypochromic anemia, an abnormal peripheral blood smear with nucleated red blood cells, and reduced amounts of hemoglobin A (HbA) on hemoglobin analysis. Individuals with thalassemia major have severe anemia and hepatosplenomegaly; they usually come to medical attention within the first two years of life. Without treatment, affected children have severe failure to thrive and shortened life expectancy. Treatment with a regular transfusion program and chelation therapy, aimed at reducing transfusion iron overload, allows for normal growth and development and extends life expectancy into the third to fifth decade. Individuals with thalassemia intermedia present later and have milder anemia that only rarely requires transfusion. These individuals are at risk for iron overload secondary to increased intestinal absorption of iron as a result of ineffective erythropoiesis.

Symptoms

Symptoms of Beta Thalassemia (Gene Promoter Involvement)
Thalassemia major is suspected in an infant or child younger than age two years with severe microcytic anemia and hepatosplenomegaly. Untreated, affected children usually manifest failure to thrive and expansion of the bone marrow to compensate for ineffective erythropoiesis.
Thalassemia intermedia is suspected in individuals who present at a later age with a milder anemia that only rarely requires treatment with blood transfusion.

Causes

Causes of Beta Thalassemia (Gene Promoter Involvement)
Clinical presentation of thalassemia major occurs between ages six and 24 months. Affected infants fail to thrive and become progressively pale. Feeding problems, diarrhea, irritability, recurrent bouts of fever, and progressive enlargement of the abdomen caused by splenomegaly may occur. If the diagnosis of thalassemia major is established at this stage and if a regular transfusion program that maintains a minimum Hb concentration of 95 to 105 g/L is initiated, growth and development are normal until age ten to 11 years.

Diagnosis

Diagnosis of Beta Thalassemia (Gene Promoter Involvement)
The diagnosis of ß-thalassemia relies on measuring red blood cell indices that reveal microcytic hypochromic anemia, nucleated red blood cells on peripheral blood smear, hemoglobin analysis that reveals decreased amounts of HbA and increased amounts of hemoglobin F (HbF) after age 12 months, and the clinical severity of anemia. Molecular genetic testing of the gene encoding the hemoglobin subunit beta (HBB) is available in clinical laboratories and may be useful for predicting the clinical phenotype in some cases as well as presymptomatic diagnosis of at-risk family members and prenatal diagnosis.

Treatment

Treatment of Beta Thalassemia (Gene Promoter Involvement)
Treatment Of Beta-Thalassemia (Gene Promoter Involvement):

1. Blood Transfusions
2. Iron Chelation Therapy
3. Folic Acid Supplements
4. Blood and Marrow Stem Cell Transplant

Prognosis

Prognosis of Beta Thalassemia (Gene Promoter Involvement)
Consult with your doctor.

Prevention

Prevention of Beta Thalassemia (Gene Promoter Involvement)
Consult with your doctor.