Thalassemia is inherited, meaning that at least one of your parents must be a carrier of the disease. It’s due to either a genetic mutation or a deletion of certain key gene fragments.
The two main forms of thalassemia are alpha-thalassemia and beta-thalassemia. In alpha-thalassemia, at least one of the alpha globin genes has a mutation or abnormality. In beta-thalassemia, the beta globin genes are affected.
Each of these two forms of thalassemia has several distinct types. The exact form you have will affect the severity of your symptoms and prognosis.Alpha-Thalassemia
Alpha-thalassemia also has two serious types, which are hemoglobin H disease and hydrops fetalis.
Hemoglobin H disease can cause bone issues. The cheeks, forehead, and jaw may all overgrow. Additionally, hemoglobin H disease can cause:
jaundice, which is a yellowing of the skin or the whites of the eyes
an extremely enlarged spleen
malnourishment
Hydrops fetalis is an extremely severe form of thalassemia. It occurs before birth. Most individuals with this condition are either stillborn or die shortly after being born.Beta ThalassemiaPeople whose hemoglobin does not produce enough beta protein have beta thalassemia. It is found in people of Mediterranean descent, such as Italians and Greeks, and is also found in the Arabian Peninsula, Iran, Africa, Southeast Asia and southern China.
There are three types of beta thalassemia that also range from mild to severe in their effect on the body.
Thalassemia Minor or Thalassemia Trait. In this condition, the lack of beta protein is not great enough to cause problems in the normal functioning of the hemoglobin. A person with this condition simply carries the genetic trait for thalassemia and will usually experience no health problems other than a possible mild anemia. As in mild alpha thalassemia, physicians often mistake the small red blood cells of the person with beta thalassemia minor as a sign of iron-deficiency anemia and incorrectly prescribe iron supplements.
Thalassemia Intermedia. In this condition the lack of beta protein in the hemoglobin is great enough to cause a moderately severe anemia and significant health problems, including bone deformities and enlargement of the spleen. However, there is a wide range in the clinical severity of this condition, and the borderline between thalassemia intermedia and the most severe form, thalassemia major, can be confusing. The deciding factor seems to be the amount of blood transfusions required by the patient. The more dependent the patient is on blood transfusions, the more likely he or she is to be classified as thalassemia major. Generally speaking, patients with thalassemia intermedia need blood transfusions to improve their quality of life, but not in order to survive.
Thalassemia Major or Cooley’s Anemia. This is the most severe form of beta thalassemia in which the complete lack of beta protein in the hemoglobin causes a life-threatening anemia that requires regular blood transfusions and extensive ongoing medical care. These extensive, lifelong blood transfusions lead to iron-overload which must be treated with chelation therapy to prevent early death from organ failure.Causes Hemoglobin is made of two proteins: Alpha globin and beta globin. Thalassemia occurs when there is a defect in a gene that helps control production of one of these proteins.
There are two main types of thalassemia:
Alpha thalassemia occurs when a gene or genes related to the alpha globin protein are missing or changed (mutated).
Beta thalassemia occurs when similar gene defects affect production of the beta globin protein.
Alpha thalassemias occur most often in persons from Southeast Asia, the Middle East, China, and in those of African descent.
Beta thalassemias occur most often in persons of Mediterranean origin. To a lesser extent, Chinese, other Asians, and African Americans can be affected.
There are many forms of thalassemia. Each type has many different subtypes. Both alpha and beta thalassemia include the following two forms:
Thalassemia major
Thalassemia minor
You must inherit the gene defect from both parents to develop thalassemia major.
Thalassemia minor occurs if you receive the faulty gene from only one parent. Persons with this form of the disorder are carriers of the disease. Most of the time, they do not have symptoms.
Beta thalassemia major is also called Cooley's anemia.
Risk factors for thalassemia include:
Asian, Chinese, Mediterranean, or African American ethnicity
Family history of the disorder
Symptoms
The most severe form of alpha thalassemia major causes stillbirth (death of the unborn baby during birth or the late stages of pregnancy).
Children born with thalessemia major (Cooley's anemia) are normal at birth, but develop severe anemia during the first year of life.
Other symptoms can include:
Bone deformities in the face
Fatigue
Growth failure
Shortness of breath
Yellow skin (jaundice)
Persons with the minor form of alpha and beta thalassemia have small red blood cells but no symptoms.Alpha thalassemia silent carriers generally have no signs or symptoms of the disorder. The lack of alpha globin protein is so minor that the body's hemoglobin works normally.Mild Anemia
People who have alpha or beta thalassemia trait can have mild anemia. However, many people who have these types of thalassemia have no signs or symptoms.
Mild anemia can make you feel tired. Mild anemia caused by alpha thalassemia trait might be mistaken for iron-deficiency anemia.
Mild to Moderate Anemia and Other Signs and Symptoms
People who have beta thalassemia intermedia have mild to moderate anemia. They also may have other health problems, such as:
Slowed growth and delayed puberty. Anemia can slow down a child's growth and development.
Bone problems. Thalassemia may cause bone marrow to expand. Bone marrow is the spongy substance inside bones that makes blood cells. When bone marrow expands, the bones become wider than normal. They may become brittle and break easily.
An enlarged spleen. The spleen is an organ that helps your body fight infection and remove unwanted material. When a person has thalassemia, the spleen has to work very hard. As a result, the spleen becomes larger than normal. This makes anemia worse. If the spleen becomes too large, it must be removed.
Severe Anemia and Other Signs and Symptoms
People who have hemoglobin H disease or beta thalassemia major (also called Cooley's anemia) have severe thalassemia. Signs and symptoms usually occur within the first 2 years of life. They may include severe anemia and other health problems, such as:
A pale and listless appearance
Poor appetite
Dark urine (a sign that red blood cells are breaking down)
Slowed growth and delayed puberty
Jaundice (a yellowish color of the skin or whites of the eyes)
An enlarged spleen, liver, or heart
Bone problems (especially with bones in the face)