Sickle cell disease (SCD) is an inherited blood disorder characterized by the possession of two abnormal hemoglobin, one of which is hemoglobin S.
Normal red blood cells are smooth, flexible discs like the letter O. This enables them to move easily through blood vessels. However, sickle cells are stiff, sticky and shaped like a crescent. They tend to cluster together, making it difficult for them to move through small blood vessels. These clusters block the blood vessels, stopping the movement of healthy, oxygen-carrying blood. Oxygen delivery to the tissues will be reduced, causing pain and organ dysfunction. This is responsible for the majority of the complications of this disease.
The spleen is an organ which helps filter blood and so recycles old red blood cells. It tends to destroy the misshaped sickle cells faster than normal red blood cells. Normal red blood cells live for about 120 days while the sickle cells only live for about 14 days. This results in a chronic lack of oxygen-carrying red blood cells called anemia. Sickle cells tend to destroy the spleen, increasing the risk of potentially life-threatening bacterial infections.
It is estimated that nearly 300, 000 infants with sickle cell disease are born each year. It mostly affects children of African descent, Hispanics and Caribbean ancestry, but is also found in those with Middle Eastern, Indian, Latin American and Mediterranean heritage.
TYPES OF SICKLE CELL DISEASE
Children with sickle cell disease inherit sickle cell trait from at least one parent.
Sickle cell trait is having one copy of the HbS gene and one copy of the normal hemoglobin A gene (HbA). Sickle cell trait is not a form of sickle cell disease, although in rare circumstances they can become symptomatic. People with sickle cell trait may pass on the HbS gene to their children.
There are different types of sickle cell disease that differ in symptoms and severity. The type of sickle cell disease depends on the specific gene variant that your child has inherited.
The types include:
Sickle cell anemia (HbSS) – this is the most common type of sickle cell disease. The child inherits one HbS gene from each parent. Chronic anemia is present and a variety of symptoms and complications occur.
Sickle cell with hemoglobin C disease (HbSC) – The child has one HbS gene and one defective hemoglobin C gene (HbC). Mild to moderate anemia is typical and complications may occur but to a milder degree.
Hemoglobin S-β-thalassemia – this has two forms; HbSβ° and HbSβ+. The child has one HbS gene and one β thalassemia gene. The degree of anemia is variable depending on the specific genetic type. There is a broad range of sickle cell symptoms and disease severity.
MAJOR SYMPTOMS OF SCD
Below are a few of the symptoms a child with sickle cell disease may experience:
- Vaso-occlusive crisis also known as pain crisis. This is when blood flow is blocked by the sickle cells. Pain can occur anywhere but most commonly; arms, legs, chest and spine. Painful swelling of the hands and feet can occur in infants and is known as dactylitis. Priapism which is a painful, unwanted erection occurs when the sickle cells block blood flow in the penis.
- Acute Chest Syndrome – this occurs when the sickle cells block the flow of oxygen in the lungs. It can be life threatening and is the leading cause of death in children with sickle cell disease.
- Abdominal pain, especially in the splenic area.
DIAGNOSIS OF SCD IN CHILDREN
Any child with suspected sickle cell disease should be taken immediately to a doctor.
A number of lab investigations would be done, a few include:
• Full Blood Count (FBC)
• Sickling test
• Hemoglobin electrophoresis
TREATMENT OF SCD
Treatment is aimed at preventing the development of sickle cell crises, to identify and manage any precipitating cause and to manage sickle cell crises and complications.
- Hydration with intravenous fluids and oral fluid intake.
- Analgesics for pain relief.
- Antibiotics for any bacterial infection.
- Antimalarial for malaria.
- Folic Acid.
PREVENTION OF SCD AND COMPLICATIONS IN CHILDREN
- Genetic counselling and parental education.
- Children should avoid precipitating causes of crisis, eg. Malaria, pneumonia, exposure to extremes of weather and strenuous physical activities.
- Encourage drinking plenty of fluids to prevent dehydration.
- Children should have a good nutritional state.
- Daily intake of folic acid.
- There should be prompt treatment of infections.
• Standard Treatment Guidelines, Sixth Edition