Dr. M.J. Bazos, MD. Patient Handout
THALASSEMIA MINOR

About Your Diagnosis

Thalassemic anemia is a term that defines a genetically transmitted anemia common to certain populations worldwide. Thalassemia minor is a hereditary disease. That means one or both of your parents must have the abnormal gene for the offspring to have the disease. The more severe types are called
thalassemia intermedia and thalassemia major. These conditions are easily recognized, usually occur among infants and children, necessitate many blood
transfusions, and have other findings such as skeletal changes or an enlarged liver and spleen. Thalassemia minor usually is asymptomatic. Patients have mild anemia that usually is found during a routine blood analysis. A blood smear also shows characteristic changes consistent with the diagnosis. Anemia happens when one of the necessary tools for the production of red blood cells is either deficient or decreased in number. Thalassemia belongs to the first category. Because of an alteration on the gene responsible for production of a main component of the red blood cells, these cells are destroyed, and anemia occurs. Thalassemia is subdivided into alpha and beta types. Alpha-thalassemia is transmitted by four different genes, two inherited from the father and two from the mother. When two of the four are absent, thalassemia minor occurs. Beta-thalassemia is transmitted by two genes, one from the father and one from the mother. When one is absent thalassemia minor occurs. It is speculated that red blood cells that have the thalassemia characteristics are less susceptible to infestation by certain parasites, specifically the malaria parasite. This confers an advantage in some areas of the world, and it is there that thalassemia is most common. These areas are Africa, the Mediterranean, and Southeast Asia. Patients whose ancestors came from these areas also are at increased risk. The most important aspect of thalassemia minor is prevention of the more severe types. Being aware of carrying the genetic alteration always raises the question of transmitting it to one’s offspring. It is recommended that persons with thalassemia minor ask their partners to undergo medical evaluation, especially if they belong to any of the risk groups. If both partners have thalassemia minor, there is risk for transmitting thalassemia intermedia or thalassemia major to their offspring. The percentage varies according to the number of genes missing. There are centers that can study the blood in detail to give accurate numbers, and many of these specialized centers even offer fetal testing.

Living With Your Diagnosis
Thalassemia minor is usually asymptomatic. It is diagnosed either when a routine blood test shows mild anemia or microcytosis (small red blood cells) or through examinations of family members of patients with more severe forms of thalassemia. Rare patients with thalassemia minor may have mild symptoms of anemia, such as fatigue or shortness of breath with exercise. Because thalassemia minor is a genetic disorder, persons who have it may transmit it to their children. This is usually not a problem for the child unless both parents have a genetic red blood cell abnormality, in which case, the child may be affected by a severe form of thalassemia (thalassemia major, thalassemia intermedia, or sickle thalassemia, to name a few). Therefore persons with thalassemia minor and their partners may want to consider genetic counseling when they decide to have a baby.

Treatment
Patients with thalassemia minor usually do not need treatment.
The DOs
• Take folic acid supplements as prescribed by your physician if you are pregnant.
• Stop exercising if you become fatigued.
• Seek genetic counseling if you are planning to start a family to determine your risk for having a baby with this condition.
The DON’Ts
• Do not take a vitamin supplement that contains iron without consulting your physician. Some types of thalassemia are associated with increased absorption of iron, and taking iron supplements for a prolonged period of time may lead to iron overload.
• Avoid overexertion.
When to Call Your Doctor
• If you experience severe fatigue, chest pain, or shortness of breath. Because the anemia of thalassemia minor is mild, most persons with this disorder do not have medical emergencies due to the thalassemia.
Websites:
MedWeb Hematology: http://www.gen.emory.edu/medweb.hematology.html
MedMark Hematology: http://medmark.bit.co.kr/hematol.html
Joint Center for Sickle Cell and Thalassemic Disorders:
http://cancer.mgh.harvard.edu/medOnc/sickle.htm