Sickle Cell Anemia

1 What is sickle cell anemia?

Sickle cell anemia is an inherited blood disorder characterized by abnormally shaped red blood cells that block the flow of blood. This is a genetic disorder which affects the structure of hemoglobin.

This disease is not contagious like a cold or cough, so it cannot pass from one person to another. This disease is inherited, which means it is passed by genes from parents to their children.

The distorted red blood cells are prone to rupture, resulting in increased destruction. Obstruction of blood vessels by sickle-shaped cells may damage the organ and cause pain.

It is more prevalent among Africans and African-Americans. Two mutated genes inherited from the parents result in this condition.

There is no complete cure for sickle cell. Treatment strategies focus on managing the symptoms. 

People who have sickle cell disease inherit two abnormal hemoglobin genes, which is one from each parent. At least one of the two abnormal genes causes a person’s body to create hemoglobin S. If a person has two hemoglobin S genes (hemoglobin SS), it is then referred to as sickle cell anemia. This is one of the most common and severe kinds of sickle cell diseases. The HBB gene is the one responsible for the production of beta-globin, an important protein present in hemoglobin. If this HBB gene undergoes mutation, then an abnormal beta-globin is produced. This is also known as hemoglobin S. The abnormal beta-globin distorts the shape of the red blood cells into the sickle shape.

Overview of normal hemoglobin and sickle hemoglobin

There are minute cells in tissues which need a constant and steady supply of oxygen to function well. The hemoglobin in red blood cells takes up the oxygen in the lungs which are carried to all the tissues and cells of the body.

These red blood cells which contain the normal hemoglobin are disc shaped. This shape allows the cells to be more flexible so that they can easily move and pass through the large and small blood vessels to provide oxygen.

Sickle hemoglobin is not like normal hemoglobin. They can form stiff rods within these red cells. These sickle shaped cells are not flexible like normal red cells, and can stick to blood vessel walls. This causes blockage, leading to slowing down or stopping the flow of blood. This in turn affects the supply of oxygen to nearby tissues.

This lack of oxygen in the tissue can cause severe panic attacks and pain. These attacks and pain occur without any warning sign. To get these treated the person would need to go to the hospital.

These sickle shaped red blood cells undergo premature death since they cannot function properly due to their shape. This leads to anemia. Sickle cells damage the spleen which is an important organ for fighting infections in the body.

2 Symptoms

All symptoms of sickle cell anemia are caused by the abnormally shaped red blood cells that block the flow of blood in blood vessels.

Those people affected with sickle cell anemia start to show signs of the disease during the first year of life. This is usually around five months of age. The symptoms and complications of sickle cell anemia vary for each individual and also can range from mild to severe.

Impaired circulation affects the delivery of oxygen to tissues. Symptoms and severity vary with the organ and the extent of involvement.

The main symptoms of sickle cell anemia are:

  • Anemia: Distorted red blood cells are fragile and tend to rupture too soon. This results in a shortage of red blood cells in the body, a condition called anemia. Lack of red blood cells affects the oxygen delivery to tissues and organs.
  • Pain crises: Deficiency of oxygen in tissues causes sudden, severe bouts og pain called pain crises. Pain starts when the blood flow is blocked by the sickle-shaped red blood cells, particularly in the chest, abdomen, and joints. The intensity, frequency, and duration of pain varies from person to person. It may last for a few hours or days. Some people may have only few episodes of pain crises, while others have frequent pain crises attacks.
  • Swelling in hands and feet: Obstruction of blood flow by the sickle cells result in swollen hands and feet in babies. This is often the first indication of sickle cell anemia.
  • Frequent infections: Sickle cells damage the spleen and this reduces the infection-fighting ability of the body.
  • Delayed growth: A shortage of red blood cells affects the delivery of oxygen and nutrients to different parts of the body. This restricts growth in children and delays puberty in teenagers.
  • Vision problems: Sickle cells may block the tiny blood vessels in the eyes, resulting in vision problems. The patient may also experience yellowing in the eyes.

The patient suffers intense pain because the joints do not get enough oxygen. The surface of the hip bones becomes irregular and there is roughage due to reduced supply of blood. In such cases, patients may require joint replacement surgery other than oral medications.

Some other symptoms include skin and nail beds turning pale, a yellowish tint to the whites of the eyes or skin, sudden paralysis or numbness in arms, legs, and face, fever, dizziness, coldness in hands and feet, and headaches.

The reason that infants do not show such symptoms during birth is because fetal hemoglobin protects their red blood cells from sickling. However, when the baby turns four to five months old, these fetal hemoglobin get replaced by sickle hemoglobin and the cells begin to sickle.

3 Causes

Sickle cell anemia is caused by a gene mutation that results in the production of abnormal hemoglobin. This causes the red blood cells that carry hemoglobin to be distorted, rigid, and sticky.

Sickle cell anemia is passed from parents to offspring as an autosomal recessive inheritance. In this type of inheritance, a child who gets a mutated gene from each of the parent develops the disease.

If the child receives only one faulty gene, the condition is referred to as a sickle cell trait. It is asymptomatic, as these children can make both distorted and healthy hemoglobin. Patients with sickle cell trait are considered carriers and can pass on the mutated gene to the next generation.

The major risk factor for developing sickle cell anemia is the presence of the mutated gene in both parents. Sickle cell anemia is more common in Africa, India, Mediterranean countries, Saudi Arabia, South and Central America, and the Caribbean islands.

4 Making a diagnosis

Sickle cell anemia is diagnosed by blood test. The diagnostic blood test checks for the presence of hemoglobin S, the abnormal hemoglobin produced in sickle cell anemia.

It is this hemoglobin S that causes distorted red blood cells. Additional tests are recommended to identify the amount of sickle cells.

People with the sickle cell trait will have low amounts of sickle cells when compared to anemia caused by two gene mutations.

Chorionic villus sampling and amniocentesis are two tests used to diagnose sickle cell anemia prenatally.

Both of these procedures use samples of fetal cells for analysis. 

Blood tests can be conducted on newborns as well as adults or older children. There are two types of sickle cell anemia that are genetically transmitted. In some cases, where both the parents are carriers of hemoglobin S, the child has a risk of developing sickle cell anemia or even thalassemia.

It is important that the child is diagnosed early with the disease. Couples are urged to undergo prenatal testing if it is found that the parents are at risk of passing sickle cell anemia to their child.

5 Treatment

Sickle cell anemia is a disease that worsens over time. Treatment of sickle cell anemia is developed around symptom management and preventing complications to lengthen the lives of those who have this condition. Treatment options can vary for each person depending on symptoms and severity of the disease.

Medications, blood transfusions, supplemental oxygen, and bone marrow transplant are the common methods used in controlling symptoms of anemia.

One can live a normal life if sickle cell anemia is detected early. Late diagnosis can make treatment more painful and debilitating. 


Antibiotics are prescribed to prevent infections. These drugs are started as early as 2 months of age and continued for 5 years. Over-the-counter pain medications and hydroxyurea are suggested to relieve pain crises. Hydroxyurea stimulates the production of fetal hemoglobin, a form that blocks the production of abnormal hemoglobin.

Vaccinations during childhood are also important in preventing infections. For adults, pneumococcal vaccine and annual flu shots prevents severe infections.

Blood transfusions increase the level of red blood cells, and thus aid in relieving anemia.

Breathing masks help to supplement oxygen and reduce breathing difficulties.

Stem cell transplant or bone marrow transplant is a procedure in which defective bone marrow is replaced by healthy marrow from a suitable donor. In this procedure, the defective bone marrow is destroyed by chemotherapy or radiation therapy. Stem cells from the healthy donor are then infused into the blood, which migrate to the bone marrow.

These new stem cells produce normal hemoglobin and red blood cells, alleviating symptoms of anemia. After the stem cell transplant, medications are given to prevent the rejection of the stem cells from the donor.

Antibiotics, vitamins, blood transfusions, painkillers, and other medications are used to control complications, if any.

Complications from stem cell transplants and hydroxyurea are rare, but can be serious or life-threatening. Therefore, the families of people suffering with this disease should check with the doctor about the risks and benefits of each treatment.

6 Prevention

As sickle cell anemia is an inherited disease, genetic counseling is the only way to prevent having a child with the mutations. 

Genetic counseling helps to understand the risk of having a child with this condition.

7 Alternative and homeopathic remedies

Remember that there is no cure for sickle cell anemia, and all treatments, including homeopathic remedies, are aimed to alleviate symptoms.

Homeopathic remedies used to alleviate symptoms of sickle cell anemia include:

  • Ferrum metallicum
  • Ferrum protoxalate
  • Ferrum phosphoricum
  • Fatrum muriaticum
  • Frsenicum
  • Phosphorous

Fish oil is also suggested to reduce the frequency of pain crises.

Zinc supplements help to prevent cell damage caused by sickle cell anemia. 

Speak with your doctor before you begin any home remedies for sickle cell anemia.

8 Lifestyle and coping

Lifestyle modifications are necessary for your child in order to cope with sickle cell anemia.

Children with sickle cell anemia have special needs at school.

Teachers and friends can support the child to make up for the absences due to the disease.

Having a good support system at school and home is essential to cope.

Ensure that they have plenty of fluids and adequate rest. Folic acid supplements and a healthy diet help to avoid complications. Drink at least 8 to 10 glasses of water every day and eat healthy food. Try not to get too hot or cold.

Learn more about how to control pain during pain crises. 

You'll likely be referred to a hematologist, who can provide specialized individualized care.

Ensure regular health checkups to prevent any untoward incident. Babies from birth to one year should see a doctor every two to three months.

Children between the age of one to two years should see the doctor at least every three months and those above the age of two or older should visit the doctor at least once a year.

Illnesses such as flu caused due to infection should be avoided at all costs, since it can be very dangerous for a child with sickle cell anemia disease.

Try and participate in light physical activity to help stay healthy. However, avoid becoming too tired. Rest is also very important.

Sickle Cell Anemia

9 Risks and Complications

Sickle cell anemia may lead to a number of complications such as:

  • Stroke
  • Acute chest syndrome
  • Organ damage
  • Pulmonary hypertension or high blood pressure in the lungs
  • Vision problems or blindness
  • Skin ulcers
  • Gallstones
  • Blockage of blood flow to the lungs leading to acute chest syndrome

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