Sickle Cell Disease
What Is Sickle Cell Disease?
Sickle cell disease is an inherited blood disorder that affects red blood cells. People with sickle cell disease have red blood cells that contain mostly haemoglobin S, an abnormal type of haemoglobin. Sometimes these red blood cells become sickle-shaped (crescent shaped) and have difficulty passing through small blood vessels. When sickle-shaped cells block small blood vessels, less blood can reach that part of the body. Tissue that does not receive a normal blood flow eventually becomes damaged. This is what causes the complications of sickle cell disease. There is currently no universal cure for sickle cell disease.
Haemoglobin is the main substance of the red blood cell. It helps red blood cells carry oxygen from the air in our lungs to all parts of the body. Normal red blood cells contain haemoglobin A. Normal red blood cells that contain haemoglobin A are soft and round and can squeeze through tiny blood tubes (vessels). Normally, red blood cells live for about 120 days before new ones replace them.
People with sickle cell conditions make a different form of haemoglobin A called haemoglobin S (S stands for sickle). Red blood cells containing mostly haemoglobin S do not live as long as normal red blood cells (normally about 16 days). They also become stiff, distorted in shape and have difficulty passing through the body’s small blood vessels.
Sickle cell conditions are inherited from parents in much the same way as blood type, hair colour and texture, eye colour and other physical traits. The types of haemoglobin a person makes in the red blood cells depend upon what haemoglobin genes the person inherits from his or her parents. Like most genes, haemoglobin genes are inherited in two sets, one from each parent.
If both parents have Sickle Cell Trait (AS), they have 1 in 4 (25%) chance of having a child with Sickle Cell Disease at every pregnancy.
Types of Sickle Cell Disease
The most common are:
The majority of individuals with sickle cell disease have haemoglobin S, but some make a different type of abnormal haemoglobin like haemoglobin C, haemoglobin D, or haemoglobin E. Also, some individuals can have sickle cell disease because of co-inheritance of beta thalassemia. It is important to speak to your physician to understand what type you have.
If one parent has Sickle Cell Anaemia (SS disease) and the other is Normal, all of the children will have sickle cell trait (AS)
Symptoms of sickle cell disease
People with SCD start to have signs of the disease during the first year of life, usually around 5 months of age. Early symptoms of SCD may include:
Effects of the disease varies per each individual and can change over time. The signs and symptoms of Sickle Cell relates to many of the disease complications.
If one parent has Sickle Cell Anaemia (SS) and the other has Sickle Cell Trait (AS), there is a 50% chance (or 1 out of 2) of having a baby with either sickle cell disease or sickle cell trait with each pregnancy.
Common complications of SCD
“Pain Episode” or “Crisis”:
Acute Chest Syndrome (ACS):
Stroke: Sickle cells can clog blood flow to the brain and cause a stroke. A stroke can result in lifelong disabilities and learning problems.
Sickle cell disease or Sickle Cell Trait (SCD) diagnosis