Frequently Asked Questions About Sickle Cell Disease

Frequently Asked Questions

1) What is sickle cell disease?
Sickle cell disease is an inherited disorder that affects red blood cells. People with sickle cell disease have red blood cells that become hard and pointed instead of soft and round. Sickle cells cause anemia, pain and many other problems.

2) What is sickle cell trait?
A person who inherits the sickle cell gene from one parent and the normal type of that gene from the other parent is said to have sickle cell trait. One in 12 African-Americans in this country has sickle cell trait. Carriers of the sickle cell gene generally are as healthy as noncarriers. Sickle cell trait cannot change to become sickle cell disease. However, when two people with sickle cell trait have a child, their child may inherit two sickle cell genes and have the disorder.

3) If sickle cell trait is not an illness, why are people tested?
Babies are tested to see if they have sickle cell disease. Teens and adults are tested mainly to see if they can have a baby with the disease.

5) What are the chances that parents with sickle cell trait will pass it on to their children?
There is a 50 percent chance that a child born to parents who both carry a sickle cell gene will have the trait. There is a 25 percent chance that the child will have sickle cell disease. There also is a 25 percent chance that the child will have neither the trait nor the disease. These chances are the same in each pregnancy.
If only one parent has the trait and the other has no abnormal hemoglobin gene, there is no chance that their children will have sickle cell disease. However, there is a 50-50 chance of each child having the trait.

4) What medical problems are caused by sickle cell disease?
Lung tissue damage, pain episodes and stroke. The blockage of blood flow caused by sickled cells also causes damage to most organs including the spleen, kidneys and liver.

5) How many people have sickle cell disease?
Sickle cell disease is a global health problem. In the United States it is estimated that over 70,000 people have sickle cell disease. About 1,000 babies are born with the disease each year in America.

6) How long does a person with sickle cell disease live?
The average life expectancy in America has improved. It is now in the mid 40 years of age range.

7) Are people of African descent the only group affected?
No. It is also present in Portuguese, Spanish, French Corsicans, Sardinians, Sicilians, mainland Italians, Greeks, Turks and Cypriots. Sickle cell disease also appears in Middle Eastern countries and Asia.

8) Is there a cure?
A small number of children with severe sickle cell disease have been cured through a blood stem cell transplant. The stem cells (immature cells that develop into blood cells) come from bone marrow, or less frequently from umbilical cord blood, usually donated by siblings who are a good genetic match. Most children with sickle cell disease, however, do not have siblings who are good genetic matches. For this reason, researchers have recently begun performing stem cell transplants using umbilical cord blood from unrelated donors with apparent success.
About 150 children worldwide with sickle cell disease have had blood stem cell transplants, and about 85 percent of them appear to be cured of the disease. However, this approach carries a high risk: about 5 percent of children who underwent bone marrow transplants died. The transplant did not cure the disease in another 10 percent. Gene therapy may someday offer a cure with less risk.

Currently, researchers are studying a number of new drug treatments, in addition to hydroxyurea, for reducing complications of the disease. Like hydroxyurea, decitabine and butyrate (a food additive) appear to cause the body to make a form of hemoglobin (fetal hemoglobin) that the baby makes before birth. Increased levels of fetal hemoglobin appear to help prevent red blood cells from sickling. Recent studies also suggest that inhaling the gas nitric oxide or taking an oral dietary supplement called L-arginine (which appears to boost the body’s production of nitric oxide) may also help prevent sickling, as may treatment with an antifungal drug called clotimazole or some blood-thinning drugs. There has already been a great deal of progress in medical care that reduces serious complications and improves survival in individuals with sickle cell disease. These and other new treatments may further improve the quality of life in affected individuals.

9) What are some promising treatment developments?
The use of hydroxyurea has shown promising results on some adult sickle cell patients. It reduces the frequency of severe pain, acute chest syndrome and the need for blood transfusions.

10) Can people with sickle cell disease live a productive life?
Yes. But like all patients with chronic disease, sickle cell patients are best managed in a comprehensive multi-disciplinary program of care and a strong extended support system.

11) Can a person catch sickle cell disease from someone who has it?
No. The disease is inherited and is not contagious. To inherit the disease, a child must receive two sickle cell genes, one from each parent.

12) Do we all have the same chance of inheriting sickle cell disease?
No. In the United States, most cases occur among African-Americans and Hispanic-Americans. About one in every 500 African-Americans has sickle cell disease. It also affects people of Arabian, Greek, Maltese, Italian, Sardinian, Turkish and Indian ancestry.

Can a woman with sickle cell disease have a safe pregnancy?
Yes. However, women with sickle cell disease are at increased risk of complications that can affect their health and that of their babies. During pregnancy, the disease may become more severe and pain episodes may occur more frequently. A pregnant woman with sickle cell disease is at increased risk of preterm and of having a low-birthweight baby. However, with early prenatal care and careful monitoring throughout pregnancy, women with sickle cell disease can have a healthy pregnancy. If the baby’s father has sickle cell trait, the baby has a 50 percent chance of having the disease. If he does not, the baby will have only the trait.

Is there a test for sickle cell disease or trait?
Yes. A person can have a blood test to find out if he has either sickle cell trait or a form of the disease. There also are prenatal tests to find out if the baby will have the disease or carry the trait. If both parents have the sickle cell trait, in three out of four cases, the prenatal test will show that the baby will not have sickle cell disease.

Where is sickle cell testing and treatment available?
Couples who are planning to have a baby can get carrier testing at medical centers and sickle cell treatment facilities. A genetic counselor can refer a couple for testing and discuss the risks to their offspring. Other sources of testing and treatment include the hospital pediatric or hematology (blood) departments. Couples also can check with their doctor or the Sickle Cell Disease Association of America for resources in their area.