Overview

A sickle cell disease is an inherited group of disorders that affects the body's red blood cells. People with SCD usually have defective haemoglobin molecules in their red blood cells that cause them to take on a sickle shape rather than the usual peacock tail shape. These sickle cells are more fragile, causing them to break apart easily and not last for long in the bloodstream. The resulting decrease in RBC can cause anaemia and organ damage.

What Causes Sickle Cell Disease?

Sickle Cell disease is caused by a genetic mutation in the beta-globin gene responsible for producing the oxygen-carrying protein haemoglobin. This mutation produces haemoglobin S, which causes red blood cells to take on an abnormal sickle shape. This mutation is inherited in a recessive manner, meaning both parents must carry the mutated gene for offspring to develop SCD. Those with only one mutated gene are symptom-free and called carriers.

What Are the Symptoms of Sickle Cell Disease?

The symptoms of sickle cell disease can vary from person to person. Common signs and symptoms are mentioned below:

- Fatigue
- Chronic kidney diseases
- Shortness of breath
- Pain and discomfort
- Chest pain
- Swelling in arms and legs
- Jaundice
- Muscle weakness
- Inflammation
- Delayed development
- Infection

Link Between Sickle Cell Anaemia and Kidney Disease

Due to their abnormality, blood cells cannot carry enough oxygen to other body parts, such as the kidney. The sickled cells also block blood flow through tiny blood vessels to the kidneys and other organs. The reduced delivery of oxygen to the kidney cells causes them to die. This leads to kidney disease, but early and ongoing medical care helps minimise the complications of sickle cell disease.

Several studies have well-established the link between sickle cell anaemia and kidney disease. As per researchers, patients with sickle cell anaemia are more likely to suffer from kidney disease than those without the condition.

The primary reason behind the link between sickle cell anaemia and kidney disease is the association between hemolysis and kidney impairment. Hemolysis- the breaking down of red blood cells- is a common problem among those with SCA, and it can cause a host of kidney-related issues.

There is an increased risk of nephrotic syndrome, proteinuria, and end-stage renal disease among people with SCA, though the exact cause is still unknown.

Complications Associated With Sickle Cell Disease

Sickle cell disease can cause serious medical problems and sometimes can be life-threatening. These complications may include

- Pain
- Anaemia
- Organ damage such as kidney, liver, and lungs
- Infection
- Pulmonary hypertension
- Vision problems
- Blood clot formation in the arteries

Following a doctor's treatment plan can keep sickle cell anaemia under control and reduce the risk of other serious problems.

How Is Sickle Cell Disease Diagnosed?

Sickle cell disease is usually diagnosed by genetic testing or blood tests. A doctor may also perform a physical examination and enquire about the lifestyle and family history.

Blood test - This test checks the levels of haemoglobin in the blood and examination of the blood film prepared on a glass slide to determine whether a person has sickle cell disease. It is one of the simple tests that can be done to raise the suspicion as to whether or not someone has sickle cell disease.

Hb Electrophoresis - To identify the different blood cells, doctors also performed Hb electrophoresis. The blood test for sickle cell disease can help detect signs of the disease earlier and can help determine whether or not treatment is needed. It can also help families make informed decisions about treatment and care.

Genetic testing - This test is used to detect the genetic mutation responsible for this abnormal haemoglobin and determine whether a child has sickle cell disease or sickle cell trait in cases where the diagnosis is in doubt following the above tests or if the child is recently transfused, where the results of HbS are obscured. This test can be done in the laboratory at birth or at any other time.

What Treatment Options Are Available for Sickle Cell Disease?

Treatment for sickle cell disease includes medications and other therapies to help patients cope with the pain and complications of the condition.

Medication

Medications help reduce the symptoms of sickle cell anaemia. Some common medications include Crizanlizumab (Adakveo), hydroxyurea (Siklos, Droxia, and Hydrea), voxelotor, L-glutamine oral powder, and pain-relieving medications.

Blood transfusion and Exchange Transfusion

Blood transfusions are one of the most effective treatments for sickle cell disease. Transfusing healthy red blood cells from a donor can help to improve the patient's overall health and reduce the risk of complications, when the Hb level of the patient is less than 8 gm%. However, when the symptoms are predominantly of pain, a chest crisis or a brain stroke with a higher Hb, a procedure called ‘exchange transfusion’ is often employed. In this process depending on the patient’s Hb and HbS levels, patient’s blood is exchanged with normal healthy donor blood through an apheresis machine. This process is usually carried out without major complications.

Stem cell transplant (or bone marrow transplant)

The only known cure for sickle cell disease is a bone marrow transplantation (BMT) from a HLA-matched family donor called ALLOGENEIC BMT.

ALLOGENEIC BMT was first carried out in 1980 in a patient with Acute Leukemia who also had Sickle Cell Disease. Subseuqently, multicentric studies on BMT in Sickle Cell Disease has taken place in USA, France and Belgium.

These show that 90% of the most severely affected patients with Sickle Cell Disease are cured with BMT from Matched Family Donors.

However, very few patients with Sickle Cell Disease have a Matched Family Donor. The Unrelated Donor Registries rarely offer a full matched donor for these patients.

BMT in Sickle Cell Disease has produced the best results one can expect in any severe inherited disorder. Despite such encouraging results, BMT in Sickle Cell Disease had hit a roadblock due to lack of suitably matched donors.

Recent studies have shown that ‘Haploidentical BMT’ can cure the majority of patients with Sickle Cell Disease without any severe complication. ‘Haploidentical BMT’ is a procedure, where the donor is a HLA-half matched family donor. Such transplants require a lot of experience and expertise, along with proper infrastructure and follow-up.

When to Consult a Doctor

You can also get in touch with the expert Haematologist at Narayana Healthcare based in your city to get immediate attention and medical support during an injury, disorder or any other health concern.

Conclusion

Sickle cell disease is a serious but manageable genetic disorder. It can be detected with blood tests and treated with medications and surgery.

FAQs:

Q. What are the 4 main symptoms of sickle cell disease? A. The 4 main symptoms of sickle cell disease include anaemia, episodes of extreme pain (called pain crises), jaundice, and chest problems.

Q. What is sickle cell disease caused by? Ans. It’s caused by an abnormality in the haemoglobin protein responsible for carrying oxygen throughout the body. Haemoglobin molecules are found inside red blood cells, and they give these cells their characteristic biconcave shape.

Q. What Treatments Are Available for Sickle Cell Disease? A. Treatment for sickle cell disease typically includes medications and surgery. Drugs that reduce the amount of oxygen in the blood may also be prescribed.

Q. How Is Sickle Cell Disease Detected? A. Sickle cell disease can be detected by blood tests that measure the levels of specific proteins in the blood. These proteins can change over time and may help identify the presence of the disease.

Q. Can sickle cells go back to normal? A. When the cells are deprived of oxygen, they take on a sickle shape; once they get enough oxygen supply, they return to their normal shape. Another potential way to restore normal blood cell function in sickle cell patients is through blood transfusion and gene therapy.