Beta Thalassemia Health Article

Diagnosis

Completing a family history, performing a complete physical examination, and results of blood (hematological) tests can lead to a diagnosis of beta thalassemia. Bone abnormalities and masses or enlarged organs may be recognized during physical examination. Prenatal testing to detect beta thalassemia can be done by completing an amniocentesis (obtaining a sample of amniotic fluid, which surrounds the fetus during pregnancy). Lab results will vary depending on the type of beta thalassemia that an individual presents with.

Normal hemoglobin results are 13-18 g/dL for males and 12-16 g/dL for women. Normal red blood cell counts are 4.7-6.1 million for males and 4.2-5.4 million for females. In individuals with beta zero form of beta thalassemia major, there will be no HbA present in the blood.

Symptoms of beta thalassemia minor may be similar to those of sideroblastic anemia (a disorder characterized by low levels of hemoglobin, fatigue, and weakness) and sickle cell disease (a disease that changes red blood cell shape, rendering it incapable of functioning).

Symptoms of beta thalassemia major may be similar to those of hereditary spheocytic hemolytic anemia (presence of sphere shaped red blood cells).

Treatment and management

Beta thalassemia minima and minor usually require no treatment. Pregnant women that suffer from beta thalassemia minor may require blood transfusions to keep hemoglobin levels normal. Individuals with beta thalassemia intermedia and major can be treated with blood transfusions and iron chelation (binding and isolation of metal) therapy. Although individuals with beta thalassemia intermedia do not usually require transfusions, in certain cases it may be necessary.

Blood transfusions are performed in individuals that present with severe symptoms such as anemia and impaired growth and development. Children may receive transfusions every four to six weeks. A high risk associated with transfusions is iron overload, which is fatal. Iron overload results from inadequate amounts of serum transferring (a molecule that exchanges iron between body tissues), which is needed to bind and detoxify iron. Iron accumulation can lead to dysfunction of the heart, liver, and endocrine glands.

Monitoring iron levels in the body is essential. Individuals receiving blood transfusions should keep total body iron levels at 3-7 mg of iron per gram of body weight. There are three methods of measuring iron levels in the body. These include a serum ferritin test, liver biopsy, and radiological study performed by the Superconducting Quantum Interference Device (SQUID).

The serum ferritin (iron storage protein) test is completed by testing a blood sample for ferritin content. This method is the easiest and most affordable way of testing for body content of iron, but it is not reliable. A liver biopsy is an invasive procedure that requires removal of a small piece of the liver. Studies have shown that a liver biopsy is very accurate in measuring the level of iron stores in the body. The third method, which requires a Superconducting Quantum Interference Device, is also very accurate in measuring iron stores. The SQUID is a highly specialized machine and few centers in the world possess this advanced technology.

Iron overload can be prevented with the use of iron chelating therapy. Chelating agents attract the excess iron and assist with the process of binding and detoxifying this iron in the body. The drug deferoxamine (desferol) is one of the most widely used iron chelating agents. Treatment is completed through nightly infusions of deferoxamine by a pump or with daily intramuscular injections. Infusion by pump is used for the administration of high doses and low doses are given through injections. Iron chelation therapy by oral administration with a drug named deferiprone has been under experimental study and may be an alternative to deferoxamine.

Individuals receiving blood transfusions should pay close attention to iron intake in the diet. It is recommended that children under age 10 keep dietary iron intake at 10 mg/day or less. Individuals age 11 or older should keep dietary iron intake at 18 mg/day or less. Foods high in iron include: beef, beans, liver, pork, peanut butter, infant cereal, cream of wheat, prunes, spinach, raisins, and leafy green vegetables. Individuals should read food labels and avoid using cast iron cookware, which can provide more iron in food during cooking.

Increased amounts of iron in the body can cause a decrease in calcium levels, which impairs organs that aid in building strong bones. Individuals with beta thalassemia major are at risk for developing osteoporosis (disease resulting in weakened bones). Increased dietary intake of calcium and vitamin D can help increase the storage of calcium in the bones, thus making the bones stronger and decreasing the risk for osteoporosis.

Bone marrow transplantation is another form of treatment for beta thalassemia. Outcomes of transplantation are greatly influenced by the health of the individual. This form of treatment is only possible if the individual has a suitable donor.

Researchers are investigating the use of the drugs hydroxyurea and butyrate compounds to increase the amounts of fetal and total hemoglobin in individuals with beta thalassemia. Studies using gene therapy, such a stem cell replacement, are also being conducted.

Social and lifestyle issues Children with beta thalassemia major that is not diagnosed and treated early may develop changes in the bone structure of the face due to the expansion of bone marrow. Supportive counseling may benefit children who feel inadequate or refuse to participate in social activities due to their appearance.

Adolescents may require counseling concerning the effects that blood transfusions and iron chelation therapy may have on their social lifestyle.

Parents may need to seek counseling or attend support groups that focus on the time demand and lifestyle changes of caring for a child diagnosed with beta thalassemia.