Sickle cell anemia is one of a group of sickle cell diseases.
Sickle cell anemia is a blood disease that causes abnormal red blood cells. Africans, African Americans, and East Indians have a high risk of the disease. This is also true for people from the Mediterranean (Italian or Greek), Middle East, Caribbean, and Central or South America. In the US, 1 of every 12 African-American newborns carries the sickle cell trait in his or her genes. About 1 of every 500 African American newborns have this lifelong disease.
Sickle cell anemia is inherited. If a baby's parents have the disease or both are carriers, the baby may inherit the sickle cell genes. If a child inherits a sickle cell gene from each parent, the child has 2 genes and will have sickle cell anemia. If the child inherits the gene from just one parent, the child will not have the disease. However, he or she is a carrier and could pass the gene to his or her children.
The red blood cells carry oxygen from the lungs to the rest of the body. A chemical in the red blood cells called hemoglobin helps the cells carry oxygen. If your child has sickle cell anemia, most of the red blood cells have an abnormal type of hemoglobin called hemoglobin S. The abnormal hemoglobin can change the shape of the blood cells. Instead of being soft and round, the cells are a stiff crescent (sickle) shape. This shape makes it harder for the blood cells to pass through small blood vessels. The cells can get stuck and block the flow of blood and oxygen to parts of the body. The lack of oxygen can damage the body tissues. It can also cause severe pain and fever.
The abnormal blood cells are fragile and don’t last as long as normal red blood cells. Your child’s body may not be able to make new red blood cells fast enough. This can cause a shortage of red blood cells. The shortage of red blood cells is called anemia.
Sickle cell anemia is one of 3 common types of sickle cell disease in the US. The other 2 types are called hemoglobin SC disease and sickle thalassemia. The 3 conditions differ in the types and amounts of abnormal hemoglobin in the blood.
Babies are born with a kind of hemoglobin that protects the red blood cells from sickling right away. Around age 4 to 5 months, this hemoglobin is replaced by "adult" hemoglobin and the cells start to sickle. After 4 months of age, symptoms are often brought on by an infection. The symptoms may include:
Toddlers and children may have frequent pain with or without any other signs of illness.
Most children and adults with sickle cell anemia have times when they have symptoms and times when they do not have symptoms. Crises are the times when abnormal red blood cells block the flow of blood, causing symptoms. The most common symptom of a sickle cell crisis is pain. The pain is usually felt in the part of the body where the sickling cells are blocking blood flow. Crises may start suddenly and last from a few days to several weeks. Times when you have no symptoms are called remissions.
Sickle cell anemia can cause the skin to look pale as the anemia worsens. The paleness may be most obvious on the inside of the eyelids, under fingernails, and in the creases of the palms of the hands. The skin may also turn yellow (become jaundiced).
One of the life-threatening complications of sickle cell anemia can be anemia that is sudden and severe. A severe shortage of normal red blood cells may cause weakness, shortness of breath, or even heart failure. The symptoms of shock caused by heart failure are low blood pressure, rapid pulse, and decreasing consciousness.
In the US, sickle cell anemia is usually diagnosed at birth after an abnormal result from a newborn screening test. Another blood test called hemoglobin electrophoresis is then done for final diagnosis. This test may also be done to see if someone carries the gene for sickle cell anemia.
If your child did not have the screening test when he or she was a newborn, your child may first have a blood test called a complete blood count (CBC). The CBC looks for anemia and sickle-shaped red blood cells. Then your child may have a hemoglobin electrophoresis test.
Sickle cell anemia can be diagnosed before birth with DNA testing of a baby's cells. The cells can be obtained with amniocentesis or chorionic villus sampling (CVS) during pregnancy.
If your child has a sickle cell crisis, he or she will be given IV fluids and pain medicine. Your child will need to rest. If too many red blood cells are destroyed during the crisis, a blood transfusion may be needed.
Hydroxyurea is a medicine that may be used to try to prevent sickle cell crisis. Taken daily, it should help your child have fewer crises. It can also shorten how long each crisis lasts. It is still being studied, especially to see if there are any long-term side effects.
Researchers are looking for other medicines that may treat the symptoms of sickle cell anemia. They are also studying bone marrow and stem cell transplants and other techniques as possible ways to cure sickle cell disease
Taking iron supplements does not help people with sickle cell disease. Sickle cell anemia is not caused by too little iron in the blood. It is caused by not having enough red blood cells. Taking iron supplements can be harmful because the extra iron builds up in the body and can damage the organs.
Because abnormal red blood cells are circulating throughout your child’s body, problems can happen in any part of the body. Some of the possible problems are:
High blood pressure in the lungs is a common complication of sickle cell anemia. This problem is called pulmonary hypertension. It can cause trouble breathing and heart damage.
Acute chest syndrome is another possible problem. Acute chest syndrome happens when there is sickling of red blood cells in the lungs. The usual symptoms are fever and chest pain or pressure. Other symptoms may include a cough or shortness of breath. Like infections and stroke, acute chest syndrome can be life threatening and needs medical care right away.
If your child has sickle cell anemia, it is very important for your child to have a healthcare provider who is familiar with sickle cell disease—someone who knows how to treat it and how to prevent complications. Your child should see your provider regularly. You need to develop a good working relationship with your provider to learn how to care for your child at home. You also need to learn which symptoms need medical care right away.
Children with sickle cell anemia are more likely to have serious infections, ranging from flu to pneumonia. Prevention of infections is an important part of the treatment because they can cause a sickle cell crisis. To help prevent infections you should check with your child’s provider to:
One of the most important things to do for children under the age of 5 is to give your child antibiotics every day to prevent infection. Pneumonia and other infections caused by bacteria can be deadly to a child with sickle cell disease. It also helps to keep your child away from people who have infections and to teach your child to wash his or her hands often.
To try to prevent sickle cell crises, avoid conditions that lower the blood oxygen, such as:
Also try to avoid dehydration. A loss of too much fluid from the body can cause sickling.
Follow your child’s healthcare provider's instructions. Ask your provider:
Make sure you know when your child should come back for a checkup.
For more information, contact:
Because sickle cell anemia is inherited, it can be prevented if couples who each carry the sickle cell trait gene do not have children. Screening tests can show if you are a carrier. When both parents are carriers, each child has a 25% risk of having sickle cell anemia and a 50% risk of being a carrier. If you are thinking about having a child and have sickle cell anemia or are a carrier, it’s a good idea to seek genetic counseling. If you are African American or a member of one of the other racial or ethnic groups where the gene is common and don’t know if you are a carrier or not, you and your partner should consider being tested if you are thinking of having children.