What is sickle cell disorder?
Sickle cell disorder is an inherited genetic disorder that affects red blood cells. People with sickle cell disorder have red blood cells that become hard and pointed instead of soft and round. Sickle cells cause anemia, pain and many other problems.
What is sickle cell trait?
If you have sickle cell trait, you have inherited the gene for sickle cell disease. Sickle cell trait does not turn into sickle cell disorder. If someone has sickle cell trait and his partner has sickle cell trait they may produce a child with sickle cell anaemia.
What medical problems are caused by sickle cell disorder?
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.
Are people of Africa and 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.
Is there a cure?
There is no universal cure for sickle cell disease. Research in gene therapy, the ultimate universal cure, is currently underway. 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 disorder, 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 disorder 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 disorder 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.
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.
How many people have sickle cell disorder?
Sickle cell disease is a global health problem. In Nigeria one in every four persons are carriers of the sickle cell gene. It is estimated that over 150,000 babies are born with symptomatic sickle cell anaemia each year in the country.
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.
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.
Can a person catch sickle cell disorder 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.
Can a woman with sickle cell disorder 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 disorder 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 disorder. There also are prenatal tests to find out if the baby will have the disorder 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 disorder.
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 Foundation Nigeria for resources in their area.