Beta thalassemia Health Article

Beta thalassemia minor

Individuals with this type of beta thalassemia may be asymptomatic or experience very few symptoms. Symptoms may be worse in individuals that are pregnant, under stress, or malnourished. Symptoms may include:

• Fatigue. This may be the only symptom that an individual with beta thalassemia minor exhibits. Fatigue is caused by the decreased oxygen carrying capacity of the red blood cells, resulting in lowered oxygenation for cells and tissues.
• Anemia. Anemia is a decrease in the amount of hemoglobin in the blood. Hemoglobin is needed to carry oxygen on the red blood cells. In beta thalassemia minor there is a decrease in adult hemoglobin (HbA) and an increase in hemoglobin A2. Hemoglobin A2 is a minor hemoglobin that contains delta globin chains in the place of beta globin chains. Anemia is most likely to occur during pregnancy.
• Splenomegaly. Enlargement of the spleen may occur due to increased removal of defective red blood cells. This is rarely seen in individuals with beta thalassemia minor and may be accompanied by pain in the upper left portion of the abdomen.
• Skin. The skin color of individuals with beta thalassemia minor may be pale (pallor) due to oxygen deprivation in blood.

Beta thalassemia intermedia

Individuals with this form of beta thalassemia usually begin to show symptoms during toddler or preschool years. These individuals present with many of the same symptoms as beta thalassemia major, however, symptoms for beta thalassemia intermedia are less severe and may include:

• Anemia. In individuals with beta thalssemia intermedia, hemoglobin levels are greater than 7g/dl but they are less than normal. Normal levels for hemoglobin are 13-18 for males and 12-16 for females.
• Hyperbilirubinemia. Bilirubin is a yellow pigment of bile that is formed by the breakdown of hemoglobin in the red blood cells. Excess amounts of bilirubin in the blood is caused by the increased destruction of red blood cells (hemolysis) by the spleen.
• Splenomegaly. Enlargement of the spleen is caused by increased removal of defective red blood cells. Red blood cells are defective due to the increased amount of inclusion bodies caused by circulation of free alpha globin chains.
• Hepatomegaly. Enlargement of the liver may be caused by a build-up of bile due to increased amounts of bilirubin in the blood.
• Additional abnormalities. Individuals with beta thalassemia intermedia may have a yellow discoloration (jaundice) of the skin, eyes, and mucous membranes caused by increased amounts of bilirubin in the blood. Individuals may also suffer from delayed growth and abnormal facial appearance.

Beta thalassemia major

Individuals with this form of beta thalassemia present with symptoms during the first year after birth. Symptoms are severe and may include:

• Severe anemia. Individuals with beta thalassemia major suffer from a hemoglobin level of less than 7 mg/dl.
• Hyperbilirubinemia. Individuals will have an increased amount of bilirubin in the blood. This is due to the increased destruction of red blood cells (hemolysis) by the spleen.
• Jaundice. Individuals may experience a yellow discoloration of the skin, eyes, and mucous membranes caused by increased amounts of bilirubin in the blood.
• Extramedullary hematopoiesis. Abnormal formation of red blood cells outside of the bone marrow may occur in the body's attempt to compensate for decreased production of mature red blood cells. This can cause masses or the enlargement of organs, which may be felt during physical examination.
• Splenomegaly. Enlargement of the spleen may result due to increased destruction of red blood cells and the occurrence of extramedullary hematopoiesis.
• Hepatomegaly. Enlargement of the liver may result due to accumulation of bile or the occurrence of extramedullary hematopoiesis.
• Cholithiasis. This is the presence of stones in the gallbladder, which may lead to blockage and cause bile to be pushed back into the liver.
• Bone marrow expansion. The bone marrow becomes expanded due to the increase of the production of red blood cells (erythropoiesis) in an attempt to produce more mature red blood cells and decrease the anemic state of the body.
• Facial changes. Due to expansion of the bone marrow, children will develop prominent cheekbones, depression of the nasal bridge, and protrusion of the upper jaw. These facial changes are a classic sign in children with untreated beta thalassemia.
• Iron overload. Iron overload of the tissues can be fatal and is due to erythroid (red blood cell) expansion. The increased destruction of a vast amount of red blood cells causes increased amounts of iron to be released from the hemoglobin.
• Cardiovascular abnormalities. Accumulation of iron deposits in the heart muscle can lead to cardiac abnormalities and possibly cardiac failure.
• Additional abnormalities. Individuals may also suffer from pale skin, fatigue, poor feeding, failure to thrive, and decreased growth and development.