Hereditary Spherocytosis: Understanding Inherited Hemolytic Anemia
Updated: 3 days ago
Medically reviewed by Dr. Baraa Alnahhal, MD · Last reviewed: October 2026
Quick Answer: What is Hereditary Spherocytosis?
Hereditary spherocytosis (HS) is a genetic condition present from birth in which the body makes abnormal, sphere-shaped red blood cells. These rigid, fragile cells are destroyed too quickly by the spleen, causing anemia and high bilirubin levels that can lead to jaundice and gallstones. Treatment focuses on managing symptoms and preventing complications such as gallstones.
What the research says
Diagnosis starts with simple tests. The 2011 British guidelines on HS describe the diagnostic tests, including the eosin-5-maleimide (EMA) binding test, and say that membrane protein assays and genetic analysis are rarely needed, mainly for atypical cases. They also update the surgical advice, including when to consider removing the gallbladder together with the spleen, and recognize further long-term hazards of splenectomy (Bolton-Maggs et al., British Journal of Haematology, 2012) [2].
Splenectomy works for HS, but carries trade-offs. A review reports that splenectomy is curative in most patients with HS, but that growing recognition of its long-term risks has led doctors to re-evaluate its role, and guidelines recommend discussion between clinicians, patient and family (Gallagher, Pediatric Clinics of North America, 2013) [3].
Expert recommendations note infection and clot concerns. European recommendations state that the effectiveness of splenectomy is well documented in HS, unlike in other hereditary hemolytic anemias, while noting short- and long-term infectious and thrombotic complications. They were based on expert opinion because no randomized trials were found (Iolascon et al., Haematologica, 2017) [4].
Key Takeaways
Feature | Hereditary Spherocytosis (HS) Details |
|---|---|
Primary Cause | Inherited variants in genes that build the red blood cell membrane [1]. |
Prevalence | About 1 in 2,000 people of Northern European ancestry [1]. |
Common Signs | Anemia, jaundice, enlarged spleen, and gallstones [1]. |
Inheritance | Autosomal dominant (about 75%) or autosomal recessive (about 25%) [1]. |
Diagnosis | Blood count and smear, osmotic fragility, other lab tests, and genetic testing [1]. |
Main Treatment | Folate, transfusions, and in some cases splenectomy [1]. |
The Mechanics of Spherocytes
The problem in HS lies in the red blood cell membrane. Normal red cells are biconcave disks, a shape that makes them flexible enough to squeeze through tiny capillaries and spring back [1].
In HS, genetic variants weaken the cell membrane. As the cells travel through the circulation, pieces of membrane break off and the cell becomes a rigid sphere [1]. The spleen readily detects and destroys these spherocytes, leaving a chronic shortage of healthy red blood cells [1].
Symptoms and Associated Complications
Severity varies widely, often depending on how fast red cells are destroyed. Many people have mild symptoms and are not diagnosed until adulthood, while others face significant problems from birth.
Common symptoms and secondary conditions include:
Anemia symptoms: chronic fatigue, shortness of breath, pale skin and a fast heartbeat [1].
Neonatal jaundice: yellowing of the skin and eyes in newborns from a buildup of bilirubin, a byproduct of broken-down blood cells [1].
Splenomegaly: an enlarged spleen from working overtime to remove rigid spherocytes [1].
Gallstones: excess bilirubin from hemolysis can form stones in the gallbladder, causing abdominal pain and nausea [1].
Genetic Inheritance and Risk Factors
HS is the most common cause of inherited chronic hemolytic anemia in people of Northern European and North American descent, affecting about 1 in 2,000 individuals. It is less common in African American and Southeast Asian populations [1].
It follows two main inheritance patterns:
Diagnostic Procedures
Providers begin with family history and a physical exam to check for an enlarged spleen, then use lab tests to confirm the diagnosis [1].
Complete blood count (CBC): measures the number and health of red blood cells [1].
Peripheral blood smear: looks under the microscope for sphere-shaped cells [1].
Osmotic fragility test: shows how easily red cells break down in different salt concentrations [1].
Other lab tests: a Coombs test to rule out other causes of hemolysis, and Band 3 protein testing [1].
Genetic testing: identifies the specific gene variant [1].
Management and Treatment Strategies
There is no cure for the underlying gene change, but the symptoms of HS can be managed well enough to support a high quality of life.
Folate supplements: folic acid helps the body make new red blood cells to replace those destroyed [1].
Blood transfusions: used for severe anemia to supply healthy donor cells [1].
Phototherapy: light treatment that helps newborns clear excess bilirubin and resolve jaundice [1].
Splenectomy: surgical removal of the spleen can reduce red cell destruction and ease anemia, but living without a spleen can make it harder to fight infections, so providers weigh the benefits against the risks. People who have their spleen removed need extra vaccines (such as pneumococcal, meningococcal and Hib) and should treat any fever as an emergency and seek care right away [1].
Prognosis and Long-Term Outlook
Most people with HS lead full, healthy lives with a normal life expectancy [1]. Lifelong care aims to monitor blood counts and prevent complications such as gallstones and, after splenectomy, serious infections. Regular follow-up with a hematologist is essential as the condition changes over time.
Frequently Asked Questions
What makes HS different from other types of anemia?
HS is caused by the abnormal shape and fragility of red blood cells (spheres), not by a lack of iron or other nutrients.
Can HS be cured?
HS is a genetic condition and cannot be cured at the gene level, but it can be managed very effectively. Splenectomy reduces red cell destruction and is curative of the anemia in most patients.
Is a splenectomy always necessary?
No. It is usually reserved for moderate to severe cases where anemia significantly affects quality of life. Doctors weigh the benefits against the infection risk.
Why does HS cause jaundice?
Jaundice comes from high bilirubin, a waste product released when red blood cells break down too quickly.
Can HS be diagnosed in adults?
Yes. Mild cases may go unnoticed until adulthood, when symptoms such as gallstones appear.
What is a spherocyte?
A red blood cell that has lost its disk shape and become a rigid sphere.
How common is HS?
HS affects about 1 in 2,000 people of Northern European ancestry.
Is HS contagious?
No. It is an inherited genetic condition and cannot be spread.
What are the risks of living without a spleen?
The main risk is a higher susceptibility to certain bacterial infections, so doctors weigh this carefully before recommending surgery.
Can people with HS exercise?
Most can lead active lives. If the spleen is enlarged, ask your doctor about contact or high-impact sports.
What is folate?
A B-vitamin that the body needs to make healthy red blood cells.
Do all children of a parent with HS inherit it?
In the dominant form, each child has a 50% chance of inheriting the gene change.
What is an osmotic fragility test?
A test that measures how easily red blood cells burst in different salt concentrations.
Can HS cause gallstones in children?
Yes. Chronic breakdown of red blood cells can lead to gallstones even in young children.
What is hemolysis?
The destruction of red blood cells.
Is genetic counseling recommended?
Yes, for families with a history of HS. A counselor can explain the inheritance risks.
What is neonatal jaundice?
Jaundice that occurs in the first days of a newborn's life.
Can HS be detected during pregnancy?
If the family's specific gene change is known, prenatal genetic testing is possible.
What is a blood smear?
A test in which a drop of blood is spread on a slide and examined under a microscope.
Does HS affect growth?
Severe, untreated anemia can sometimes slow growth, but this is uncommon with modern care.
Why is the spleen enlarged in HS?
The spleen works harder to filter out and destroy the abnormal spherocytes.
What is the biconcave disk shape?
The normal, flexible shape of a red blood cell, like a donut without a hole.
Can HS be mistaken for iron deficiency?
The fatigue is similar, but blood tests can tell the two apart.
Is HS more common in men or women?
HS affects both sexes equally.
What is bilirubin?
A yellowish waste product made when the body breaks down old red blood cells.
What is a peripheral blood smear?
A blood film made from an ordinary blood sample and examined for abnormal cell shapes, such as spherocytes.
Can HS cause heart palpitations?
Yes. A fast heartbeat is a common symptom of anemia because the heart works harder to deliver oxygen.
What is a partial splenectomy?
An operation that removes only part of the spleen to help preserve some immune function.
Does HS affect life expectancy?
Most people with HS have a normal life expectancy.
What are the signs of gallstones?
Sharp pain in the upper right abdomen, nausea and vomiting.
Can HS cause fatigue?
Yes. Chronic fatigue is one of the most common symptoms of the associated anemia.
What is a Coombs test?
A test that checks whether the body is making antibodies against its own red blood cells, which helps rule out other hemolytic anemias.
Why is Northern European ancestry linked to HS?
HS is most commonly diagnosed in people of Northern European descent. It is less common in African American and Southeast Asian populations.
What is the Band 3 protein?
A protein in the red blood cell membrane that helps maintain the cell's shape. Band 3 testing can be part of the diagnostic workup.
Can HS be prevented?
No, because it is genetic. Its complications, however, can often be prevented or treated.
How often should blood counts be checked?
It depends on severity, but regular monitoring is a standard part of care.
What is a hematologist?
A doctor who specializes in diagnosing and treating blood disorders.
Can HS cause shortness of breath?
Yes. With fewer healthy red blood cells, less oxygen reaches the tissues.
What is the difference between dominant and recessive HS?
In dominant HS, one changed gene from one parent is enough. In recessive HS, a changed gene is needed from both parents.
Can phototherapy be done at home?
Phototherapy is usually done in a hospital for newborns with jaundice.
What is an aplastic crisis?
A temporary stop in red blood cell production, often triggered by a viral infection.
Can HS be outgrown?
No. It is a lifelong condition.
What is the role of the bone marrow in HS?
The bone marrow works harder to make more red blood cells to make up for those being destroyed.
Is there a special diet for HS?
No special diet is required. Folate is important, so ask your care team whether you need a supplement.
Can HS cause pale skin?
Yes. Pallor is a classic sign of anemia.
What is the gallbladder?
A small organ that stores bile. Gallstones often form there in people with HS.
How does a splenectomy improve anemia?
By removing the organ that destroys spherocytes, which lets red blood cells survive longer in circulation.
What is the prognosis for children with HS?
With early diagnosis and good management, most children grow up to lead healthy lives.
Disclaimer: The information provided in this article is for educational purposes only and should not be considered medical advice. Always consult with a hematologist or genetic specialist regarding blood disorders.
Related Reading
References
Cleveland Clinic. Hereditary Spherocytosis: Symptoms, Causes & Treatment. Cleveland Clinic. Last updated January 26, 2026. https://my.clevelandclinic.org/health/diseases/23058-hereditary-spherocytosis
Bolton-Maggs PHB, Langer JC, Iolascon A, Tittensor P, King MJ. Guidelines for the diagnosis and management of hereditary spherocytosis, 2011 update. British Journal of Haematology. 2012;156(1):37-49. PMID 22055020. https://doi.org/10.1111/j.1365-2141.2011.08921.x
Gallagher PG. Abnormalities of the erythrocyte membrane. Pediatric Clinics of North America. 2013;60(6):1349-1362. PMID 24237975. https://doi.org/10.1016/j.pcl.2013.09.001
Iolascon A, Andolfo I, Barcellini W, et al. Recommendations regarding splenectomy in hereditary hemolytic anemias. Haematologica. 2017;102(8):1304-1313. PMID 28550188. https://doi.org/10.3324/haematol.2016.161166
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