Sickle Cell Disease

National Human Genome Research Institute (NHGRI) from Bethesda, MD, USA, CC BY 2.0 via Wikimedia Commons

Every year, an average of 150,000 children in Nigeria are born with sickle cell disease (SCD) widely referred to as sickle cell anaemia. About 25% of the adult population carry the sickle cell trait. 

Sickle cell disease causes severe pain and other health complications that keep the carrier in and out of the hospital with recurring illness. Despite its impact on the lives of millions, sickle cell disease is often misunderstood and overlooked. 

What is sickle cell disease?

BruceBlaus, CC BY-SA 4.0, via Wikimedia Commons

Sickle cell anaemia is a hereditary blood disorder that occurs when the body produces abnormal haemoglobin. 

The abnormal haemoglobin (HbS) works like the normal haemoglobin (commonly HbA) when the oxygen supply is optimal. 

But when oxygen supply is low, the haemoglobin molecules clump the red blood cells into stiff, sickle-shaped cells that get stuck in blood vessels, blocking oxygen flow,  leading to pain, anaemia, tissue damage, and other complications.

How is sickle cell disease inherited?

Sickle cell disease is an autosomal recessive disorder. This means that the father and mother of the child have to carry the sickle cell gene and then transmit it to their child before the child can develop the sickle cell disease. If the sickle cell gene comes only from one parent, the inheritance will lead to a sickle cell trait in the child.

Children with sickle cell gene from both parents have HbSS genotype, and therefore produce only abnormal haemoglobin (HbS). This type of haemoglobin clumps into a polymer when the oxygen content is low, which causes red blood cells to sickle.

On the other hand, those with the sickle cell trait (HbAS) have one copy of the normal haemoglobin genotype (HbA) and one abnormal copy (HbS). Such individuals produce normal and abnormal haemoglobin. 

The sickled red cells are weak and break down easily, leading to sickle cell anaemia. They can also clog blood vessels leading to painful episodes known as crises. 

Having a sickle cell trait means that, although you do not have the sickle cell disease, you may develop the symptoms in extreme conditions like strenuous exercise, high altitude, severe dehydration, or infection.

Signs and symptoms of sickle cell disease

Photo by Towfiqu barbhuiya

The symptoms of sickle cell disease can vary in severity and frequency and range from mild to severe. They typically include:

• Episodes of anaemia (low level of red blood cells),
• Joint and bone pain
• Fatigue
• Frequent and increased risk of infections
• Shortness of breath
• Yellowing of the eyes and body
• Delayed growth and development

Some individuals may also experience sudden and severe pain, known as a sickle cell crisis, caused by the blockage of blood flow in blood vessels.

Complications of sickle cell disease

Sickle cell disease can cause severe complications if it is not properly managed. Frequent sickle cell crisis, for instance, can trigger acute chest syndrome or avascular necrosis of the head of femur, a condition that leads to the death of the thigh bone.

Other complications of sickle cell disease can include:

• Stroke
• Lung damage
• liver damage
• Eye damage
• Skin ulcer

How to diagnose sickle cell disease?

If you suspect you or your child may have sickle cell disease, it is important to get a proper diagnosis. The diagnosis typically involves a blood test to determine the presence of sickled red blood cells or defective haemoglobin types. 

Haemoglobin electrophoresis can then be used confirm the diagnosis of sickle cell disease. This test detects the presence of abnormal or sickle haemoglobin and diagnoses the specific type of sickle cell disease. 

A newborn screening test can also detect the disease in infants, but this may require high-tech equipment that are available only at specialised centres. Haemoglobin electrophoresis is not useful for screening newborns because they have fetal haemoglobin which masks the presence of abnormal haemoglobin. 

Other tests, such as a complete blood count and blood film examination, can also provide important information about the disease's severity and the individual's overall health.

How can you avoid sickle cell disease? 

You can avoid sickle cell disease by:

• Getting tested: Knowing your sickle cell disease status will help you confirm your compatibility with your spouse and plan your family effectively.
• Educating yourself and others: Spread the word about sickle cell disease, its risk factors, and the importance of testing.
• Encouraging others to get tested: Encourage family and friends to get tested, especially if they are considering starting a family.
• Supporting research and advocacy: Donate to organizations working to find a cure for the disease and improve treatment options.

Sickle cell disease  is a serious condition, but it doesn't have to be a reality for future generations. By raising awareness and preventing its spread, we can help build a healthier and brighter future for all Africans.

How is sickle cell disease treated?

Sickle cell disease is managed with is a multi-disciplinary approach that includes: 

1. Pain management: medications are used during sickle cell crisis to relieve pain while rehydration prevents the blood from sickling, thus reducing the pain. 
2. Blood transfusions: Regular blood transfusions can help maintain haemoglobin levels and reduce the frequency of crises.
3. Hydroxyurea treatment: This medication increases the production of fetal haemoglobin, which can help reduce the frequency of crises, and the need for regular transfusions
4. Antibiotics: To prevent infections, patients are given prophylactic antibiotics.
5. Vaccinations: Patients with sickle  cell disease tend to be vulnerable  to infections due to their lower immunity.  Vaccinations prevent these infections.
6. Stem cell transplant: replacing sickle cells with normal ones via a stem cell transplant is a highly effective way to treat sickle cell disease. However, this is an expensive and high-risk procedure.
7. Gene therapy: This is a new and developing field in sickle cell disease treatment, aiming to correct the genetic defect causing the disease.

Living with sickle cell disease is painful and draining, but these  practical tips can help you navigate and cope with the physical and emotional demands of the disease.

• Manage pain with medication and other therapies such as hydration, rest, and exercise.
• Build a strong support system of family, friends, and medical professionals
• Connect with others who have the disease and seek educational resources
• Take care of yourself mentally and emotionally, and seek out counseling if needed
• Follow a balanced diet, avoid triggers like stress and dehydration, and

maintain regular medical checkups

Planning a Family? 

Photo by Antoni Shkraba

If you're planning to start a family, you must be aware of the risk of sickle cell disease . Here are what you can do to protect your future children:

• Get tested: Know your haemoglobin genotype and ask your partner of theirs.
• Speak to a genetic counsellor: A genetic counsellor will help you understand your risk and compatibility profile and the options available to you.
• Consider antenatal screening: Antenatal screening can help detect the disease in a developing fetus.

Taking these steps and being proactive can help reduce the risk of SCD and ensure a healthy future for your family. So start planning today and take control of your family's health!

Conclusion

Sickle cell disease is a debilitating condition affecting millions worldwide, particularly in Africa and its diaspora. Understanding the disease, its inheritance, and its management is crucial in improving outcomes and quality of life for those affected. It is important to work with your healthcare provider to find the treatment plan that works best for you. Remember, early diagnosis and treatment can improve outcomes for individuals living with sickle cell disease.