Table of ContentsView AllTable of ContentsTypesSymptomsWho’s at RiskDiagnosisTreatments
Table of ContentsView All
View All
Table of Contents
Types
Symptoms
Who’s at Risk
Diagnosis
Treatments
Alpha thalassemiais inheritedanemiawhere the body cannot produce a normal amount of hemoglobin.Hemoglobinis the protein in red blood cells that carries oxygen throughout your body.Hemoglobin A (the major hemoglobin in adults) contains alpha-globin and beta-globin chains. In alpha thalassemia, there is a reduced amount of alpha-globin chains.Andrew Brookes / Getty ImagesTypesTwo types of alphathalassemiacan lead to health problems—Hb Bart syndrome and HbH disease.Hb Bart SyndromeThis syndrome is the most severe form of alpha thalassemia. It is also known as hemoglobin Bart hydrops fetalis syndrome and alpha thalassemia major. In this syndrome, excess fluid builds up in a fetus’s body before birth. It can cause:Severe anemiaHepatosplenomegaly(enlarged liver andspleen)Heart defectsCongenital abnormalities in the urinary tract and genitalsMost babies born with Hb Bart syndrome are stillborn or die shortly after birth. In addition, the condition can cause pregnancy complications, including preeclampsia, premature birth, and bleeding.HbH DiseaseHemoglobin H (HbH) is the milder form of alpha thalassemia. The symptoms usually appear in early childhood. The condition may cause:Mild to moderate anemiaHepatosplenomegalyJaundicePeople with HbH disease usually live into adulthood.SymptomsAlpha thalassemia symptoms vary depending on the severity of the disease. Symptoms may include:AnemiaEnlarged foreheadEnlarged liver and spleenFatigueGallstonesJaundiceLeg ulcersPreeclampsia(during pregnancy)What Is Hepatomegaly?Who’s at RiskAlpha thalassemia is an inherited condition that requires both parents to be carriers. Therefore, the risk of having a child with alpha thalassemia disease depends on the status of the parents.People have four alpha-globin proteins that form theHBA1and theHBA2genes (calledalleles). When some or all of these alleles are missing, alpha thalassemia occurs.The risk is as follows:1 mutated allele: A person is a carrier with no disease symptoms. This is also known as alpha thalassemia silent.2 mutated alleles: A person may have mild alpha thalassemia symptoms (known as alpha thalassemia minor or alpha thalassemia trait).3 mutated alleles: A person has moderate to severe symptoms (HbH disease).4 mutated alleles: A fetus will have Hb Bart syndrome (alpha thalassemia major or hydrops fetalis). This condition is usually fatal before or shortly after birth.Thousands of babies are born with alpha thalassemia every year. It is most prevalent in Asia, Africa, and the Mediterranean area.Approximately 30% of African-Americans have either alpha thalassemia silent or alpha thalassemia trait.DiagnosisDiagnosing alpha thalassemia depends on the severity of the disease.Silent CarrierAlpha thalassemia silent causes no laboratory changes on acomplete blood count(CBC), which is why it is called silent carrier. Alpha thalassemia is usually suspected after a person’s child is born with HbH disease. Doctors can diagnose silent carriers with genetic testing.Alpha Thalassemia MinorOccasionally alpha thalassemia minor is identified on anewborn screenor a screening done during pregnancy if both parents are carriers, but not in all cases. A problem usually comes to light during a routine CBC.The CBC will reveal a mild to moderate anemia with very small red blood cells. Small red blood cells can beconfused with iron deficiency anemia.In general, if a doctor rules out iron deficiency anemia andbeta thalassemia trait, the person has alpha thalassemia trait. If necessary, a doctor can confirm this with genetic testing.HbH DiseaseDoctors can identify hemoglobin H on the newborn screen as well. A hematologist will monitor children with this diagnosis, closely. In addition, some patients are identified later in life during a work-up for anemia.Hb Bart SyndromeHydrops fetalis is not a specific diagnosis but rather characteristic features on aneonatal ultrasound. If a fetus has fluid accumulation (known as hydrops), a doctor will do a work-up to find the cause. In Hb Bart syndrome, four alpha-globin genes are missing.TreatmentsNo treatment is needed for people who are silent carriers (minima) or for alpha thalassemia minor. Although, people with alpha thalassemia minor will have lifelong mild anemia. Those with more moderate to severe cases may requireblood transfusionsorchelation therapy.TransfusionsPeople with HbH disease usually have moderate anemia that is well-tolerated. However, transfusions are occasionally needed during illnesses with a fever due to accelerated red blood cell breakdown.Adults may require more regular transfusions. Those with a more severe form of HbH disease (called Hemoglobin H-Constant Spring disease) can have significant anemia and require frequent transfusions during their lifetime.Iron Chelation TherapyPeople with HbH disease may developiron overload. This may occur even in the absence of blood transfusions secondary to increased absorption of iron in the small intestine. Medications called chelators can help rid the body of excess iron.SummaryAlpha thalassemia is an inherited disorder in which the body can not produce enough hemoglobin. The condition ranges from asymptomatic to severe.Sometimes, a person can be a carrier (silent alpha thalassemia) with no sign of disease. Others may have very mild disease, known as having alpha thalassemia trait.The two types of alpha thalassemia that cause health problems are Hb Bart syndrome and HbH disease. Hb Bart syndrome is diagnosed prenatally and is fatal before birth or shortly after. HbH disease is often diagnosed in childhood. However, people with HbH live well into adulthood.A Word From VerywellRemember that both parents must be carriers for a child to be born with alpha thalassemia. Doctors can diagnose alpha thalassemia with blood tests; however, a blood test won’t detect it if someone is a silent carrier.Genetic testing can confirm if you are a silent carrier. Talk to your doctor if you are concerned about alpha thalassemia. They may recommend genetic testing and blood work.
Alpha thalassemiais inheritedanemiawhere the body cannot produce a normal amount of hemoglobin.Hemoglobinis the protein in red blood cells that carries oxygen throughout your body.
Hemoglobin A (the major hemoglobin in adults) contains alpha-globin and beta-globin chains. In alpha thalassemia, there is a reduced amount of alpha-globin chains.
Andrew Brookes / Getty Images
Two types of alphathalassemiacan lead to health problems—Hb Bart syndrome and HbH disease.
Hb Bart Syndrome
This syndrome is the most severe form of alpha thalassemia. It is also known as hemoglobin Bart hydrops fetalis syndrome and alpha thalassemia major. In this syndrome, excess fluid builds up in a fetus’s body before birth. It can cause:
Most babies born with Hb Bart syndrome are stillborn or die shortly after birth. In addition, the condition can cause pregnancy complications, including preeclampsia, premature birth, and bleeding.
HbH Disease
Hemoglobin H (HbH) is the milder form of alpha thalassemia. The symptoms usually appear in early childhood. The condition may cause:
People with HbH disease usually live into adulthood.
Alpha thalassemia symptoms vary depending on the severity of the disease. Symptoms may include:
What Is Hepatomegaly?
Alpha thalassemia is an inherited condition that requires both parents to be carriers. Therefore, the risk of having a child with alpha thalassemia disease depends on the status of the parents.
People have four alpha-globin proteins that form theHBA1and theHBA2genes (calledalleles). When some or all of these alleles are missing, alpha thalassemia occurs.
The risk is as follows:
Thousands of babies are born with alpha thalassemia every year. It is most prevalent in Asia, Africa, and the Mediterranean area.Approximately 30% of African-Americans have either alpha thalassemia silent or alpha thalassemia trait.
Thousands of babies are born with alpha thalassemia every year. It is most prevalent in Asia, Africa, and the Mediterranean area.
Approximately 30% of African-Americans have either alpha thalassemia silent or alpha thalassemia trait.
Diagnosing alpha thalassemia depends on the severity of the disease.
Silent Carrier
Alpha thalassemia silent causes no laboratory changes on acomplete blood count(CBC), which is why it is called silent carrier. Alpha thalassemia is usually suspected after a person’s child is born with HbH disease. Doctors can diagnose silent carriers with genetic testing.
Alpha Thalassemia Minor
Occasionally alpha thalassemia minor is identified on anewborn screenor a screening done during pregnancy if both parents are carriers, but not in all cases. A problem usually comes to light during a routine CBC.
The CBC will reveal a mild to moderate anemia with very small red blood cells. Small red blood cells can beconfused with iron deficiency anemia.
In general, if a doctor rules out iron deficiency anemia andbeta thalassemia trait, the person has alpha thalassemia trait. If necessary, a doctor can confirm this with genetic testing.
Doctors can identify hemoglobin H on the newborn screen as well. A hematologist will monitor children with this diagnosis, closely. In addition, some patients are identified later in life during a work-up for anemia.
Hb Bart Syndrome
Hydrops fetalis is not a specific diagnosis but rather characteristic features on aneonatal ultrasound. If a fetus has fluid accumulation (known as hydrops), a doctor will do a work-up to find the cause. In Hb Bart syndrome, four alpha-globin genes are missing.
No treatment is needed for people who are silent carriers (minima) or for alpha thalassemia minor. Although, people with alpha thalassemia minor will have lifelong mild anemia. Those with more moderate to severe cases may requireblood transfusionsorchelation therapy.
Transfusions
People with HbH disease usually have moderate anemia that is well-tolerated. However, transfusions are occasionally needed during illnesses with a fever due to accelerated red blood cell breakdown.
Adults may require more regular transfusions. Those with a more severe form of HbH disease (called Hemoglobin H-Constant Spring disease) can have significant anemia and require frequent transfusions during their lifetime.
Iron Chelation Therapy
People with HbH disease may developiron overload. This may occur even in the absence of blood transfusions secondary to increased absorption of iron in the small intestine. Medications called chelators can help rid the body of excess iron.
Summary
Alpha thalassemia is an inherited disorder in which the body can not produce enough hemoglobin. The condition ranges from asymptomatic to severe.
Sometimes, a person can be a carrier (silent alpha thalassemia) with no sign of disease. Others may have very mild disease, known as having alpha thalassemia trait.
The two types of alpha thalassemia that cause health problems are Hb Bart syndrome and HbH disease. Hb Bart syndrome is diagnosed prenatally and is fatal before birth or shortly after. HbH disease is often diagnosed in childhood. However, people with HbH live well into adulthood.
A Word From Verywell
Remember that both parents must be carriers for a child to be born with alpha thalassemia. Doctors can diagnose alpha thalassemia with blood tests; however, a blood test won’t detect it if someone is a silent carrier.
Genetic testing can confirm if you are a silent carrier. Talk to your doctor if you are concerned about alpha thalassemia. They may recommend genetic testing and blood work.
4 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health: Genetic and Rare Diseases Information Center.Alpha-thalassemia.National Organization for Rare Disorders.Alpha thalassemia.National Library of Medicine: MedlinePlus.Alpha thalassemia.Naik RP, Derebail VK.The spectrum of sickle hemoglobin-related nephropathy: from sickle cell disease to sickle trait.Expert Rev Hematol. 2017;10(12):1087-1094. doi:10.1080/17474086.2017.1395279
4 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.National Institutes of Health: Genetic and Rare Diseases Information Center.Alpha-thalassemia.National Organization for Rare Disorders.Alpha thalassemia.National Library of Medicine: MedlinePlus.Alpha thalassemia.Naik RP, Derebail VK.The spectrum of sickle hemoglobin-related nephropathy: from sickle cell disease to sickle trait.Expert Rev Hematol. 2017;10(12):1087-1094. doi:10.1080/17474086.2017.1395279
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
National Institutes of Health: Genetic and Rare Diseases Information Center.Alpha-thalassemia.National Organization for Rare Disorders.Alpha thalassemia.National Library of Medicine: MedlinePlus.Alpha thalassemia.Naik RP, Derebail VK.The spectrum of sickle hemoglobin-related nephropathy: from sickle cell disease to sickle trait.Expert Rev Hematol. 2017;10(12):1087-1094. doi:10.1080/17474086.2017.1395279
National Institutes of Health: Genetic and Rare Diseases Information Center.Alpha-thalassemia.
National Organization for Rare Disorders.Alpha thalassemia.
National Library of Medicine: MedlinePlus.Alpha thalassemia.
Naik RP, Derebail VK.The spectrum of sickle hemoglobin-related nephropathy: from sickle cell disease to sickle trait.Expert Rev Hematol. 2017;10(12):1087-1094. doi:10.1080/17474086.2017.1395279
Meet Our Medical Expert Board
Share Feedback
Was this page helpful?Thanks for your feedback!What is your feedback?OtherHelpfulReport an ErrorSubmit
Was this page helpful?
Thanks for your feedback!
What is your feedback?OtherHelpfulReport an ErrorSubmit
What is your feedback?
