What Is Sickle Cell Disease?

Sickle cell disease is a condition in which red blood cells are not shaped as they should be. Red blood cells look like round discs. But in sickle cell disease, they're shaped like sickles, or crescent moons, instead.

These sickle shaped cells get stuck together and block small blood vessels. This stops blood from moving as it should, which can lead to pain and organ damage.

sickle cell

What Are the Signs & Symptoms of Sickle Cell Disease?

People with sickle cell disease can have pain crises. In a pain crisis:

  • Pain may happen in any part of the body.
  • Cold, stress, illness, or dehydration can bring on pain.
  • The pain may last a few hours, a few days, or sometimes longer.
  • Sometimes pain can be managed at home. But someone with severe pain might need treatment in a hospital.

People with sickle cell disease often have a low number of red blood cells, or anemia. Signs of anemia include:

  • paleness, often seen in the skin, lips, or nailbeds
  • tiredness
  • dizziness
  • being short of breath
  • feeling lightheaded
  • being irritable
  • trouble paying attention
  • a fast heartbeat

People with sickle cell anemia may have jaundice (skin and whites of the eyes look yellow). This happens because the sickle-shaped red blood cells break down faster than normal cells.

What Problems Can Happen?

People with sickle cell disease can have problems that need immediate care by a doctor, such as:

  • Acute chest syndrome: Caused by inflammation , infection, and blockages of small blood vessels of the lung. Signs include chest pain, coughing, trouble breathing, and fever.
  • Aplastic crisis: This is when the body temporarily does not make enough red blood cells, and can cause severe anemia. Signs include paleness, extreme tiredness, and a fast heartbeat.
  • Hand-foot syndrome: This painful swelling of the fingers and toes (also called dactylitis ) is the first sign of sickle cell anemia in some infants.
  • Infection: Kids with sickle cell disease are at risk for some bacterial infections. It's important to watch for fevers of 101°F (38°C) or higher, which can be signs of an infection. Get medical care right away if a fever happens.
  • Priapism: Males with sickle cell disease can have painful, long-lasting erections. If it's not treated quickly, damage can cause problems with getting erections later on.
  • Splenic sequestration crises: The spleen traps the abnormal red blood cells and gets very large. This can lead to a serious, quick drop in the number of red blood cells in the bloodstream. Signs include paleness, weakness or extreme tiredness, an enlarged spleen, and belly pain.
  • Stroke: Sickle-shaped cells can block small blood vessels in the brain, causing a stroke. Signs include headache, seizures, weakness in the arms and legs, speech problems, a facial droop, or loss of consciousness.

People with sickle cell disease are also at risk for problems such as leg ulcers, bone or joint damage, gallstones, kidney damage, eye damage, and delayed growth.

What Causes Sickle Cell Disease?

Sickle cell disease is a genetic condition. People who have it inherited certain hemoglobin genes from their parents. Hemoglobin is the protein inside of red blood cells that carries oxygen. Abnormal hemoglobin makes the red blood cells sickle shaped.

  • Someone who inherits a sickle cell gene from each parent has sickle cell disease.
  • Someone who inherits a sickle cell gene from one parent and a normal hemoglobin gene from the other has sickle cell trait rather than sickle cell disease. Most people with sickle cell trait don't have symptoms, but can pass the gene to their children.
  • Someone who inherits a sickle cell gene from one parent and another kind of abnormal gene from the other parent may have a different form of sickle cell disease, such as hemoglobin SC disease or sickle beta thalassemia.

How Is Sickle Cell Disease Diagnosed?

Sickle cell disease usually is found at birth with a blood test during routine newborn screening tests. A second blood test (called a hemoglobin electrophoresis) will confirm the diagnosis.

Sickle cell disease also might be diagnosed before a baby is born with a test on the amniotic fluid or with a sample of tissue from the placenta.

How Is Sickle Cell Disease Treated?

Stem cell transplant (also called bone marrow transplant) is the only known cure for sickle cell disease. Transplants are complex and risky, and for now are an option only for some patients.

Scientists are studying gene therapy for sickle cell anemia. One day, it's hoped that doctors can stop the disease by changing or replacing the abnormal gene that causes it.

But even without a cure, kids with sickle cell disease can lead fairly normal lives if they follow their treatment plan.

The treatment plan might involve:

  • Immunizations and daily doses of penicillin to help prevent infection. Kids with sickle cell disease should get all recommended vaccinations, including the pneumococcal, flu, and meningococcal vaccines.
  • Folic acid supplements, which can help kids make new red blood cells.
  • Hydroxyurea, a medicine that makes the cells less sticky. This helps decrease the frequency and intensity of painful episodes and other complications. Hydroxyurea is taken every day.
  • L-glutamine, another medicine. It's used if hydroxyurea isn't working well or someone still has pain crises even with hydroxyurea.
  • Medicines to help manage pain when it does happen.
  • Sometimes, blood transfusions for severe anemia or some complications.

When Should I Call the Doctor?

Get emergency medical care right away if your child has any of these problems:

  • fever of 101°F (38°C) or higher
  • pain that isn't getting better with medicine
  • chest pain
  • severe headaches or dizziness
  • severe stomach pain or swelling
  • shortness of breath or trouble breathing
  • extreme tiredness
  • skin that's yellow or very pale
  • an erection that is not going away or is painful
  • sudden change in vision
  • seizures
  • weakness or trouble moving part of the body
  • slurred speech
  • loss of consciousness (passing out)
  • numbness or tingling

How Can I Help My Child?

To help your child manage sickle cell disease:

  • Go to all doctor's visits and share any concerns or new symptoms.
  • Make sure your child takes all prescribed medicines.
  • Follow up with any recommended specialists to check for complications.
  • Help your child avoid pain crisis triggers, such as extreme temperatures or stress.
  • Talk to the doctor about which activities are OK for your child and which to avoid.
  • Make it clear that your child should not smoke, drink alcohol, or use drugs because these can cause pain and other problems.
  • Encourage your child to drink lots of liquids and get enough rest.
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