Learn about the symptoms, causes and treatment of this inherited blood disorder that, in the United States, is more common among Black people.
Sickle cell anemia is one of a group of inherited disorders known as sickle cell disease. It affects the shape of red blood cells, which carry oxygen to all parts of the body.
Red blood cells are usually round and flexible, so they move easily through blood vessels. In sickle cell anemia, some red blood cells are shaped like sickles or crescent moons. These sickle cells also become rigid and sticky, which can slow or block blood flow.
There's no cure for most people with sickle cell anemia. Treatments can relieve pain and help prevent complications associated with the disease.
Red blood cells are usually round and flexible. In sickle cell anemia, some red blood cells look like sickles used to cut wheat. These unusually shaped cells give the disease its name.
Signs and symptoms of sickle cell anemia usually appear around 6 months of age. They vary from person to person and may change over time. Signs and symptoms can include:
Episodes of pain. Periodic episodes of extreme pain, called pain crises, are a major symptom of sickle cell anemia. Pain develops when sickle-shaped red blood cells block blood flow through tiny blood vessels to your chest, abdomen and joints.
The pain varies in intensity and can last for a few hours to a few days. Some people have only a few pain crises a year. Others have a dozen or more a year. A severe pain crisis requires a hospital stay.
Some adolescents and adults with sickle cell anemia also have chronic pain, which can result from bone and joint damage, ulcers, and other causes.
See your health care provider right away if you or your child has symptoms of sickle cell anemia. Because children with sickle cell anemia are prone to infections, which often start with a fever and can be life-threatening, seek prompt medical attention for a fever greater than 101.5 F (38.5 C).
Seek emergency care for symptoms of stroke, which include:
Sickle cell anemia is caused by a change in the gene that tells the body to make the iron-rich compound in red blood cells called hemoglobin. Hemoglobin enables red blood cells to carry oxygen from the lungs throughout the body. The hemoglobin associated with sickle cell anemia causes red blood cells to become rigid, sticky and misshapen.
For a child to be affected, both mother and father must carry one copy of the sickle cell gene — also known as sickle cell trait — and pass both copies of the altered form to the child.
If only one parent passes the sickle cell gene to the child, that child will have the sickle cell trait. With one typical hemoglobin gene and one altered form of the gene, people with the sickle cell trait make both typical hemoglobin and sickle cell hemoglobin.
Their blood might contain some sickle cells, but they generally don't have symptoms. They're carriers of the disease, however, which means they can pass the gene to their children.
For a baby to be born with sickle cell anemia, both parents must carry a sickle cell gene. In the United States, sickle cell anemia most commonly affects people of African, Mediterranean and Middle Eastern descent.
Sickle cell anemia can lead to a host of complications, including:
If you carry the sickle cell trait, seeing a genetic counselor before trying to conceive can help you understand your risk of having a child with sickle cell anemia. A genetic counselor can also explain possible treatments, preventive measures and reproductive options.
A blood test can check for the form of hemoglobin that underlies sickle cell anemia. In the United States, this blood test is part of routine newborn screening. But older children and adults can be tested, too.
In adults, a blood sample is drawn from a vein in the arm. In young children and babies, the blood sample is usually collected from a finger or heel. The sample is then sent to a laboratory, where it's screened for the sickle cell form of hemoglobin.
If you or your child has sickle cell anemia, your doctor might suggest other tests to check for possible complications of the disease.
If you or your child carries the sickle cell gene, you'll likely be referred to a genetic counselor.
A special ultrasound machine can reveal which children have a higher risk of stroke. This painless test, which uses sound waves to measure blood flow in the brain, can be used in children as young as 2 years. Regular blood transfusions can decrease stroke risk.
Sickle cell disease can be diagnosed in an unborn baby by sampling some of the fluid surrounding the baby in the mother's womb (amniotic fluid). If you or your partner has sickle cell anemia or the sickle cell trait, ask your doctor about this screening.
Management of sickle cell anemia is usually aimed at avoiding pain episodes, relieving symptoms and preventing complications. Treatments might include medications and blood transfusions. For some children and teenagers, a stem cell transplant might cure the disease.
Children with sickle cell anemia might receive penicillin between the ages of about 2 months old until at least age 5 years. Doing so helps prevent infections, such as pneumonia, which can be life-threatening to children with sickle cell anemia.
Adults who have sickle cell anemia might need to take penicillin throughout their lives if they've had pneumonia or surgery to remove the spleen.
Childhood vaccinations are important for preventing disease in all children. They're even more important for children with sickle cell anemia because their infections can be severe.
Your child's doctor should ensure that your child receives all the recommended childhood vaccinations, as well as vaccines against pneumonia, meningitis, hepatitis B and an annual flu shot. Vaccines are also important for adults with sickle cell anemia.
During the COVID 19 pandemic, people with sickle cell anemia should take extra precautions, such as staying isolated at home as much as possible and for those who are eligible, getting vaccinated.
Blood transfusions. These are used to treat and prevent complications, such as stroke, in people with sickle cell disease.
In a red blood cell transfusion, red blood cells are removed from a supply of donated blood, then given through a vein to a person with sickle cell anemia. This increases the number of normal red blood cells, which helps reduce symptoms and complications.
Risks include an immune response to the donor blood, which can make it hard to find future donors; infection; and excess iron buildup in your body. Because excess iron can damage your heart, liver and other organs, you might need treatment to reduce iron levels if you undergo regular transfusions.
Stem cell transplant. Also known as bone marrow transplant, this procedure involves replacing bone marrow affected by sickle cell anemia with healthy bone marrow from a donor. The procedure usually uses a matched donor, such as a sibling, who doesn't have sickle cell anemia.
Because of the risks associated with a bone marrow transplant, including death, the procedure is recommended only for people, usually children, who have significant symptoms and complications of sickle cell anemia. A stem cell transplant is the only known cure for sickle cell anemia.
Clinical trials are ongoing to address stem cell transplantation in adults and gene therapies.
Taking the following steps to stay healthy might help you avoid complications of sickle cell anemia:
If you or someone in your family has sickle cell anemia, you might consider the following to help you cope:
Sickle cell anemia is usually diagnosed through genetic screening done when a baby is born. Those test results will likely be given to your family doctor or pediatrician. He or she will likely refer you to a doctor who specializes in blood disorders (hematologist) or a pediatric hematologist.
Here's information to help you get ready for your appointment.
Make a list of:
Bring a family member or friend along, if possible, to help you remember the information you're given.
For sickle cell anemia, questions to ask your health care provider include:
Don't hesitate to ask other questions.
Your doctor is likely to ask you questions, including: