Sickle Cell Anemia (SCA)
Description
Sickle cell anemia (SCA) is a chronic, inherited blood disorder that affects red blood cells. It‘s caused by a genetic mutation that leads to the production of abnormal hemoglobin, a protein in red blood cells that carries oxygen. This abnormal hemoglobin causes red blood cells to become sickle-shaped, making them stiff and sticky. These sickle cells can block blood flow, leading to pain, organ damage, and other complications. This article provides a comprehensive understanding of sickle cell anemia, covering its causes, symptoms, diagnosis, management, and strategies for thriving with the condition.
Genes Involved
Sickle cell anemia is caused by a mutation in the HBB gene, which provides instructions for making beta-globin, a protein that‘s part of hemoglobin. This gene is located on chromosome 11.
Recognizing the Signs and Symptoms
The symptoms of sickle cell anemia vary from person to person and can range from mild to severe. Some common signs and symptoms include:
- Painful episodes (crises): These episodes occur when sickle cells block blood flow, leading to pain in the bones, muscles, joints, and abdomen.
- Fatigue: Sickle cells don‘t carry oxygen as efficiently as normal red blood cells, leading to fatigue and shortness of breath.
- Delayed growth: Children with sickle cell anemia may grow more slowly than other children.
- Jaundice: The breakdown of red blood cells can lead to a yellowish tinge in the skin and eyes.
- Swelling in hands and feet: This can occur due to blocked blood flow.
- Frequent infections: Sickle cell anemia can weaken the immune system, making individuals more susceptible to infections.
- Vision problems: Damage to blood vessels in the eyes can lead to vision problems.
- Stroke: A blockage of blood flow to the brain can cause a stroke.
Causes
Sickle cell anemia is an inherited disorder, meaning it is passed down from parents to their children. Both parents must carry the sickle cell trait gene for their child to inherit sickle cell anemia. Individuals with sickle cell trait carry one copy of the sickle cell gene and one copy of the normal gene. They typically do not experience symptoms of sickle cell anemia but can pass the gene on to their children.
Inheritance/recurrence risk
Sickle cell anemia follows an autosomal recessive inheritance pattern. This means that both parents must carry the gene for the child to inherit the condition.
- If both parents have sickle cell trait, there is a 25% chance that their child will inherit sickle cell anemia, a 50% chance that their child will have sickle cell trait, and a 25% chance that their child will not inherit the gene.
- If one parent has sickle cell anemia and the other parent has sickle cell trait, there is a 50% chance that their child will inherit sickle cell anemia and a 50% chance that their child will have sickle cell trait.
- If one parent has sickle cell anemia and the other parent does not carry the gene, all their children will inherit sickle cell trait.
