Sickle Cell Anaemia: Causes, Types & Effects

What is Sickle Cell Anaemia?

Sickle cell anaemia is a type of sickle cell disease (SCD) in which a person inherits two haemoglobin S (HbS) genes, one from each parent. It is also known as HbSS disease.

Haemoglobin S can cause normally flexible red blood cells to become rigid and develop a curved or sickle-like shape. These cells can break down earlier than normal red blood cells, leading to anaemia. They may also become trapped in small blood vessels and reduce blood flow to different parts of the body.

Sickle cell anaemia is one form of the wider group of inherited conditions known as sickle cell disease. Other forms occur when the HbS gene is inherited along with another abnormal haemoglobin gene.

How Common is Sickle Cell Anaemia in India?

Sickle cell anaemia is an important public health concern in India, particularly in several tribal and other communities where the sickle cell gene is more common. The Government of India launched the National Sickle Cell Anaemia Elimination Mission in 2023 to expand screening, early diagnosis, counselling and access to comprehensive care.

According to the data from the National Sickle Cell Anaemia Elimination Mission dashboard, 42,139,843 people had been screened by 17 September 2024. Among those screened, 163,765 people (0.39%) were identified with the HbSS genotype, which is the genotype associated with sickle cell anaemia.

What are the Symptoms of Sickle Cell Anaemia?

Sickle cell anaemia is present from birth, but symptoms generally begin during infancy as the level of fetal haemoglobin decreases. The type and severity of symptoms can vary between individuals. The common symptoms of sickle cell anaemia are as follows:

Early Symptoms	Advanced Symptoms
Yellow skin or eyes	Recurrent pain episodes
Tiredness	Chronic pain
Irritability in infants	Severe anaemia
Swollen hands and feet	Breathing problems
Painful dactylitis	Recurrent infections

Early symptoms such as jaundice and tiredness are commonly linked to the faster breakdown of sickled red blood cells. Painful swelling of the hands and feet, known as dactylitis, may also be one of the first signs in infants. Symptoms can vary in frequency and severity as the condition continues over time.

Diseases Similar to Sickle Cell Anaemia

Sickle cell anaemia may share symptoms such as tiredness, weakness or pallor with other forms of anaemia. However, the cause and pattern of each condition are different.

The following comparison highlights some key differences between sickle cell anaemia, beta-thalassaemia and iron-deficiency anaemia.

Cell Anaemia vs. Beta Thalassaemia vs. Iron Deficiency Anaemia

Feature	Sickle Cell Anaemia	Beta Thalassaemia	Iron Deficiency Anaemia
Main Cause	HbS gene variant	Reduced beta-globin	Low iron levels
Type	Inherited	Inherited	Usually acquired
RBC Change	Sickling and breakdown	Reduced Hb production	Low Hb production
Key Feature	Pain crises	Chronic anaemia	Fatigue and pallor
Iron Deficiency	Not a defining feature	Not a defining feature	Main feature
Treatment Focus	Reducing sickling	Managing anaemia	Replacing iron

Beta-thalassaemia also affects the beta-globin component of haemoglobin. However, it reduces or prevents beta-globin production rather than causing the production of haemoglobin S.

Iron-deficiency anaemia develops when the body does not have enough iron to produce adequate haemoglobin and may occur due to blood loss, poor iron absorption or inadequate iron intake.

What Causes Sickle Cell Anaemia?

Sickle cell anaemia is caused by an inherited change in the HBB gene, which provides instructions for producing beta-globin, an important part of haemoglobin. This genetic change results in the production of haemoglobin S.

Under certain conditions, HbS molecules can form stiff structures inside red blood cells, causing them to become less flexible and take on a sickle-like shape. These cells also break down faster than healthy red blood cells, which can lead to chronic haemolytic anaemia.

At the same time, sickled cells may restrict normal blood flow through small blood vessels and contribute to pain and other complications.

What are the Risk Factors for Sickle Cell Anaemia

Since sickle cell anaemia is inherited, the main risk is related to the haemoglobin genes carried by the parents. The main factors associated with an increased likelihood of inheriting sickle cell anaemia include:

Sickle Cell Trait in Both Parents When both parents carry an HbS gene, their child may inherit HbS from both of them.
Other Abnormal Haemoglobin Genes An HbS gene can also combine with genes for conditions such as HbC or beta-thalassaemia and result in another form of sickle cell disease.
Family History People from families where sickle cell trait or sickle cell disease is already present may have a higher likelihood of carrying an abnormal haemoglobin gene.
Population Background Sickle cell disease is seen more frequently among people with ancestry from parts of Africa, India, the Middle East and the Mediterranean region.

When to See a Healthcare Provider?

Regular follow-up with a healthcare provider is important for people with sickle cell anaemia. Medical attention should also be sought promptly when symptoms suggest an acute complication.

Some symptoms that may require prompt medical attention include:

Severe or increasing pain
Fever
Chest pain
Difficulty breathing
Sudden weakness or numbness
Difficulty speaking
Severe tiredness or paleness
Sudden abdominal swelling in a child
A prolonged painful erection

Early assessment can help identify complications and provide timely treatment.

How is Sickle Cell Anaemia Diagnosed?

Sickle cell anaemia is diagnosed through blood tests that identify haemoglobin S and other haemoglobin variants. Screening may be offered during pregnancy, infancy or later in life, particularly for people from communities where sickle cell disease is more common or those with a relevant family history.

The common tests to diagnose sickle cell anaemia are as follows:

Newborn Screening Newborn screening can identify sickle cell disease before symptoms become apparent. Early diagnosis ensures preventive care, vaccination, regular monitoring and timely treatment.
Haemoglobin Electrophoresis Haemoglobin electrophoresis separates different haemoglobin types and can help identify HbS and other abnormal haemoglobin variants.
High-Performance Liquid Chromatography High-performance liquid chromatography (HPLC) measures different haemoglobin fractions and is commonly used to identify sickle cell disease and other haemoglobin disorders.
Complete Blood Count A complete blood count (CBC) measures haemoglobin and other blood cell parameters. This test can help assess the presence and severity of anaemia, but does not by itself confirm sickle cell anaemia.
Genetic Testing Genetic testing may be used in selected situations to identify specific haemoglobin gene variants and clarify the type of sickle cell disease.
Prenatal Testing Prenatal diagnostic testing may be considered when both parents carry relevant haemoglobin variants or when there is a known genetic risk.

Diagnostic Summary Table

following table summarises the purpose of these diagnostic tests:

Diagnostic Test	What It Helps Identify
Newborn screening	Early haemoglobin abnormality
Haemoglobin electrophoresis	Haemoglobin variants
HPLC	Haemoglobin fractions
CBC	Severity of anaemia
Genetic testing	Gene variants
Prenatal testing	Fetal genetic status

How is Sickle Cell Anaemia Treated and Managed?

Sickle cell anaemia is a lifelong condition. So treatment focuses on reducing pain episodes, preventing infections and other complications, managing anaemia and protecting organ function. The treatment plan depends on the person's age, symptoms, disease severity and complications.

The common treatments prescribed to sickle cell anaemia patients are as follows:

Disease-Modifying Treatment Hydroxyurea is used in appropriate patients. It increases fetal haemoglobin and reduces sickling-related complications, including recurrent pain episodes.
Pain Management Pain episodes should be assessed and treated promptly. Mild episodes may sometimes be managed through an individualised home-care plan, while severe or persistent pain may require treatment at a healthcare facility.
Infection Prevention People with sickle cell anaemia have an increased risk of certain infections. Preventive care for infections may include recommended vaccinations and, for eligible young children, antibiotic prophylaxis such as penicillin.
Blood Transfusions Blood transfusions may be required for selected complications or severe anaemia. They may also be used in specific situations, such as reducing the risk of stroke in high-risk patients.
Monitoring and Preventive Care Regular medical follow-up helps monitor haemoglobin levels, treatment response and possible complications involving organs such as the kidneys, lungs, eyes and bones. Maintaining adequate hydration and avoiding known triggers such as extreme temperatures and severe dehydration may also form part of individual disease-management advice.
Haematopoietic Stem Cell Transplant Haematopoietic stem cell transplantation, also known as bone marrow transplantation, is the only established potentially curative treatment for sickle cell disease. It is suitable only for selected patients because eligibility depends on factors such as disease severity, overall health and availability of an appropriate donor.

Common Medicines Used to Treat Sickle Cell Anaemia

Medicines for sickle cell anaemia are selected according to the person's age, symptoms, complications and treatment plan. They may be used to reduce sickling-related complications, prevent infections and manage pain.

Commonly used medicines and supportive treatments include:

Hydroxyurea: A disease-modifying medicine that increases fetal haemoglobin and can reduce the frequency of pain episodes and other sickle cell complications. Regular blood tests are required to monitor its effects and safety.
Pain Medicines: Medicines such as paracetamol and other prescribed analgesics may be used depending on the severity of pain. Severe pain may require hospital-based treatment.
Penicillin: Preventive penicillin may be prescribed to eligible young children to reduce the risk of serious bacterial infections.
Folic Acid: Folic acid supplementation may be recommended as part of supportive care when appropriate.

Note: The medicines used to treat sickle cell anaemia may vary according to the age, symptoms and the overall health of the patient. They should be taken under the guidance of a qualified healthcare professional.

Living With Sickle Cell Anaemia: Daily Challenges and Care

Sickle cell anaemia requires regular treatment and monitoring. The common daily challenges and caregiving requirements are as follows:

Daily Challenges
Some common day-to-day challenges may include:
- Pain Episodes: Pain crises can interrupt regular activities, work or school.
- Fatigue: Anaemia may affect energy levels and stamina.
Daily Health Management
The following measures can support day-to-day management of sickle cell anaemia:
- Treatment Routine: Taking prescribed medicines regularly can support better disease control.
- Hydration: Maintaining adequate fluid intake may help support overall health.
- Vaccination: Staying up to date with recommended vaccines is important for reducing infection risk.
- Rest and Activity: Adequate rest and activity suited to the person's health can support daily functioning.
Family and Caregiver Support Children may need help with medicines, medical appointments and recognising symptoms that need attention. Family members can also provide support during pain episodes or hospital stays.
Emotional Support Living with recurrent symptoms of sickle cell anaemia can also affect emotional well-being. Support from family, counselling and patient support groups may help individuals manage the emotional and social aspects of long-term care.
Expenses
Ongoing care for sickle cell anaemia may also involve recurring medical and related expenses, depending on the person's treatment needs. These may include:
- Medical Follow-Ups: Regular consultations and blood tests may contribute to ongoing healthcare expenses.
- Medicines: Long-term medicines may form part of recurring treatment costs.
- Hospital Care: Pain crises or other complications may occasionally require hospitalisation.
- Blood Transfusions: Some patients may require transfusion-related care as part of ongoing treatment.

What is the Prognosis for Sickle Cell Anaemia?

The prognosis for sickle cell anaemia varies from person to person. The frequency and the severity of pain episodes, infections, organ complications and access to regular medical care can all influence long-term health.

Some people may experience relatively few complications, while others may develop recurrent pain or long-term problems affecting organs such as the kidneys, lungs, eyes, liver or bones. Prompt medical attention for acute symptoms and regular follow-up can help support better long-term outcomes.

Can Sickle Cell Anaemia and Its Complications Be Prevented?

Sickle cell anaemia is an inherited condition and cannot be prevented after a child inherits the disease-causing haemoglobin variants. However, carrier screening and genetic counselling can help families understand the likelihood of passing the condition to their children. For people already living with sickle cell anaemia, preventive care can reduce the risk of some complications.

The measures that may help you become aware of the likelihood of sickle cell anaemia are as follows:

Carrier Screening Blood tests can identify people who carry sickle cell trait or other haemoglobin variants. Screening is particularly important in communities where the prevalence of sickle cell anaemia is high.
Genetic Counselling Genetic counselling helps individuals and couples understand carrier status, inheritance patterns and reproductive options.
Prenatal Testing When there is a known genetic risk, families can discuss prenatal diagnostic options with a qualified healthcare professional.
Preventing Complications Regular follow-up, recommended vaccinations, prescribed medicines, adequate hydration and timely treatment of infections can help reduce the risk of complications. Children with sickle cell anaemia may also require specific preventive measures, such as penicillin prophylaxis, as per medical advice.

Sickle Cell Anaemia Treatment Cost in India

The cost of sickle cell anaemia treatment in India can vary depending on the city, hospital, frequency of medical consultations, diagnostic tests, medicines, blood transfusions and the need for specialised procedures.

The approximate costs for sickle cell anaemia treatment are:

Treatment Component	Approximate Cost
OPD Consultation (Haematologist/Specialist Visit)	₹500-₹2,000 per consultation
Blood Tests and Monitoring (Complete Blood Count, Reticulocyte Count and Other Tests)	₹500-₹3,000 per test panel
Medicines for Disease Management	₹500-₹5,000 per month
Blood Transfusion	₹1,000-₹5,000 per transfusion
Haemoglobin Electrophoresis/HPLC	₹1,100-₹1,800 per test
Bone Marrow/Stem Cell Transplant	₹10 to ₹40 lakh

Note: The above prices are estimates and may vary in reality.

Government sickle cell programmes also support screening, counselling and disease management in participating regions.

Does Health Insurance Cover Sickle Cell Anaemia in India?

Yes. Health insurance covers treatment expenses related to sickle cell anaemia. Depending on the policy terms, the insurer will pay for in-patient hospitalisation expenses, including diagnostic tests, medicines, blood transfusion expenses, and room rent, along with bone marrow or stem cell transplantation, treatment of disease complications and pre- and post-hospitalisation expenses.

If the patient was already diagnosed with sickle cell anaemia when the policy is purchased, it may be treated as a pre-existing disease, and coverage may begin after a waiting period of 1 to 3 years.

Coverage limits, exclusions, waiting periods and sub-limits differ between health insurance plans. Therefore, the policy wording should be reviewed carefully before purchasing or making a claim.

How Much Health Insurance Coverage is Needed for Sickle Cell Anaemia?

The amount of health insurance required for sickle cell anaemia depends on the person's treatment needs, disease severity and expected healthcare expenses.

When assessing coverage, it may be useful to consider:

Frequency of hospital admissions
Need for blood transfusions
Treatment of acute complications
Access to specialist haematology care
Hospital and city of treatment
Possible stem cell transplantation
Existing employer or government health benefits

A health insurance coverage of at least ₹10 lakh to ₹20 lakh is recommended for managing sickle cell anaemia.

Since specialised procedures, such as bone marrow or stem cell transplantation, can involve substantial expenses, a higher sum insured may provide greater financial support if such treatment becomes medically necessary. Hence, a mediclaim policy with a higher sum insured of ₹25 lakh to ₹50 lakh may be suitable for advanced treatments like a bone marrow transplant.

FAQs

Q1. What is sickle cell anaemia?

Ans: Sickle cell anaemia is an inherited blood disorder in which red blood cells become abnormally shaped and can break down prematurely, causing anaemia and other complications.
Q2. What causes sickle cell anaemia?

Ans: Sickle cell anaemia is caused by inheriting two copies of the HbS variant of the HBB gene, one from each parent.
Q3. Is sickle cell anaemia hereditary?

Ans: Yes. Sickle cell anaemia is hereditary and is passed from parents to their children through specific abnormal haemoglobin genes.
Q4. What is the difference between sickle cell anaemia and sickle cell trait?

Ans: Sickle cell anaemia is a form of sickle cell disease in which a person has two HbS genes. Sickle cell trait usually occurs when a person has one HbS gene and one normal haemoglobin gene and generally does not cause the symptoms associated with sickle cell anaemia.
Q5. What are the common symptoms of sickle cell anaemia?

Ans: Common symptoms of sickle cell anaemia include anaemia-related tiredness, episodes of severe pain, jaundice, swelling of the hands and feet, and recurrent infections. Symptoms can vary between individuals.
Q6. What can trigger a sickle cell anaemia pain episode?

Ans: Sickle cell anaemia pain episodes may be triggered by dehydration, infection, extreme temperatures, low oxygen levels, and physical or emotional stress. Triggers can vary from person to person.
Q7. How is sickle cell anaemia diagnosed?

Ans: Tests like haemoglobin electrophoresis, high-performance liquid chromatography (HPLC), newborn screening and genetic testing are used to diagnose sickle cell anaemia.
Q8. Can sickle cell anaemia be detected before birth?

Ans: Yes. Sickle cell anaemia can be detected before birth through prenatal testing.
Q9. Is there a cure for sickle cell anaemia?

Ans: Haematopoietic stem cell transplantation can potentially cure sickle cell anaemia in selected patients. However, it is not suitable for everyone, and most people require long-term disease management.
Q10. How is sickle cell anaemia treated?

Ans: Doctors generally treat sickle cell anaemia with disease-modifying medicines, blood transfusions, and regular monitoring.
Q11. Is hydroxyurea used to treat sickle cell anaemia?

Ans: Yes. Hydroxyurea is a disease-modifying medicine used to reduce complications associated with sickle cell anaemia, including recurrent pain episodes.
Q12. Can sickle cell anaemia cause organ damage?

Ans: Yes. Sickle cell anaemia can cause complications affecting organs such as the kidneys, lungs, eyes, liver, and brain because repeated sickling can reduce blood flow and cause tissue damage.
Q13. Can people with sickle cell anaemia lead a normal life?

Ans: Many people with sickle cell anaemia can lead active lives with appropriate medical care and regular monitoring. The severity and course of sickle cell anaemia can vary between individuals.
Q14. Can sickle cell anaemia affect pregnancy?

Ans: Yes. Sickle cell anaemia can increase the risk of complications during pregnancy.
Q15. When does sickle cell anaemia require emergency medical care?

Ans: Sickle cell anaemia may require emergency medical care if a person develops severe or persistent pain, fever, chest pain, difficulty breathing, sudden weakness or numbness, difficulty speaking, severe pallor or fatigue, abdominal swelling, or a prolonged painful erection.

References
- https://www.cdc.gov/sickle-cell/about/index.html
- https://www.cdc.gov/sickle-cell/about/index.html
- https://www.nhlbi.nih.gov/health/sickle-cell-disease
- https://www.nhlbi.nih.gov/health/sickle-cell-disease/symptoms
- https://medlineplus.gov/genetics/condition/sickle-cell-disease/
- https://sickle.nhm.gov.in/
- https://sickle.nhm.gov.in/home/guidelines?
- https://pmc.ncbi.nlm.nih.gov/articles/PMC11489857/