What is Sickle Cell Anemia?

 

What is Sickle Cell Anemia?

Sickle cell anemia is a condition that affects the blood. It's something you inherit from your parents, which means it runs in families. In people with sickle cell anemia, the red blood cells, which normally look like round doughnuts, take on a strange, sickle shape (like a crescent moon). These sickle-shaped cells are stiff and sticky, and they can get stuck in small blood vessels. When this happens, it can cause pain and other serious health problems.

The condition is caused by a change in a gene called "hemoglobin beta" or HBB, which is located on chromosome 11. Hemoglobin is a protein in red blood cells that carries oxygen around your body. But in sickle cell anemia, this protein doesn't work quite right, which is why the red blood cells turn into that sickle shape and cause trouble.

How Does Sickle Cell Anemia Happen?

The root cause of sickle cell anemia is a mutation, or change, in the HBB gene. This condition is recessive, which means a person needs to inherit two copies of the mutated gene (one from each parent) to actually have the disease. If someone only has one copy of the gene, they won’t have sickle cell anemia, but they will be a "carrier." This means they can pass the gene to their children. If both parents are carriers, there’s a chance their child could have sickle cell anemia.

Interestingly, having just one copy of the sickle cell gene can actually make a person more resistant to malaria, a disease spread by mosquitoes. The mutated gene makes the red blood cells less hospitable to the malaria parasite, so people with the sickle cell trait (just one copy of the gene) are less likely to get seriously ill from malaria.



What Happens in the Body with Sickle Cell Anemia?

The HBB gene normally helps create hemoglobin, the protein that helps red blood cells carry oxygen. But with sickle cell anemia, a tiny change in the gene causes a big problem. Instead of producing normal hemoglobin, the body makes a version called "HbS." This abnormal hemoglobin causes the red blood cells to change shape, making them hard and sticky.

When these sickle-shaped cells try to move through the bloodstream, they can get stuck in small blood vessels. This can block the flow of blood, leading to painful episodes known as "sickle cell crises." It also means that not enough oxygen can reach parts of the body, which can cause damage to organs and tissues.

What Are the Symptoms?

The symptoms of sickle cell anemia can vary a lot from person to person. One of the most common and painful symptoms is a sickle cell crisis, which happens when the sickle-shaped cells block blood flow. This can cause sudden, severe pain, especially in the chest, abdomen, and joints. These crises can last anywhere from a few minutes to several days, or even longer.

Sickle cell anemia can lead to other serious health problems, too. For example:

  • Stroke: If blood flow to the brain is blocked, it can cause a stroke.
  • Acute chest syndrome: This happens when sickle cells block blood vessels in the lungs, making it hard to breathe.
  • Infections: The spleen, an organ that helps fight infections, can get damaged, making people with sickle cell anemia more vulnerable to infections.
  • Pulmonary hypertension: This is high blood pressure in the blood vessels that connect the heart to the lungs, which can be dangerous.

Thankfully, treatments for sickle cell anemia have improved a lot in recent years. Many people with the condition now live much longer, healthier lives than they did just a few decades ago.

How is Sickle Cell Anemia Diagnosed?

To diagnose sickle cell anemia, doctors use a simple blood test to check for the presence of the abnormal HbS hemoglobin. For babies and young children, this might involve a quick prick of the finger or heel. For adults, blood is usually drawn from a vein in the arm.

How is Sickle Cell Anemia Treated?

Treating sickle cell anemia usually means managing symptoms and preventing complications. This often involves a team of healthcare professionals, including blood disorder specialists, psychologists, social workers, and physical therapists.

Here are some common treatments:

  • Blood transfusions: Regular transfusions can help reduce the risk of complications like stroke.
  • Chelation therapy: After transfusions, this treatment helps remove excess iron from the body to prevent other health problems.
  • Antibiotics: Children under five often take daily antibiotics to protect against serious infections.
  • Pain relief: Pain medications can help manage sickle cell crises. Staying hydrated and following other lifestyle tips can also reduce the risk of these painful episodes.
  • Hydroxycarbamide: This daily medication can help the body produce a different type of hemoglobin that doesn’t cause sickle cell anemia. This can reduce the number of sickle cell crises.
  • Preventive care: Regular check-ups and tests, like brain scans to check blood flow, can help catch and prevent complications before they happen.
  • Blood and bone marrow transplants: These can potentially cure sickle cell anemia for some people, although they’re not an option for everyone.

Can We Screen for Sickle Cell Anemia?

In the UK, pregnant people are often asked about their risk of having a baby with sickle cell anemia. If both parents are carriers of the HBB mutation, their baby could be at risk. After birth, all babies in the UK are screened for sickle cell anemia using a heel-prick test.

People from high-risk groups who need general anesthesia for surgery are also tested. This is because anesthesia can reduce the amount of oxygen in the blood, which can be dangerous for someone with sickle cell anemia.

What do you think about screening newborns for conditions like sickle cell anemia?

Post a Comment

Previous Post Next Post