Sickle Cell Disease

What's the Problem?

Sickle cell disease (SCD) is a genetic condition that is inherited when a child receives two sickle cell genes – one from each parent. In SCD, the red blood cells become hard and sticky and look like a C-shaped farm tool called a “sickle.” The sickle cells die early, which causes a constant shortage of red blood cells. Also, when they travel through small blood vessels, they get stuck and clog the blood flow. This can cause pain and other serious health problems such as infection, acute chest syndrome and stroke. People with the most severe form of SCD have a 20-30 year lower life expectancy than people without SCD. The only cure for SCD is bone marrow (stem cell) transplant. However, this procedure is risky, and can have serious side effects, including death.

Who's at Risk?

SCD affects millions of people throughout the world and is particularly common among those whose ancestors came from sub-Saharan Africa; Spanish-speaking regions in the Western Hemisphere (South America, the Caribbean, and Central America); Saudi Arabia; India; and Mediterranean countries such as Turkey, Greece, and Italy. SCD is estimated to affect 90,000 to 100,000 Americans – it occurs among about 1 out of every 500 Black or African-American births, and about 1 out of every 1,400 – 1 out of every 36,000 Hispanic-American births.

What causes SCD?

SCD is a genetic condition that is present at birth. It is inherited when a child receives two sickle cell genes—one from each parent. If a person is born with it, steps should be taken to reduce complications.

People who inherit one sickle cell gene and one normal gene have sickle cell trait (SCT). People with SCT usually do not have any of the symptoms of SCD, but they can pass the trait on to their children. It’s possible to have the trait and not know it. If someone in a family has the trait or the disease, others in that family might have it too. If a person has the trait, there is a 50% chance that he or she could pass the trait on to his or her children. If that person’s partner also has the trait, their children will have a 25% chance of having SCD. This is true for every pregnancy.  Therefore, it is very important that people know their “sickle cell status” and the easiest way to find this out is to have a blood test. Tests are available through primary care providers, ob-gyns, or SCD community based organizations.

People who are at high risk of having a child with SCD and are planning to have children may want to consider genetic counseling. A counselor can explain the risk (likelihood) of having a child who has the disease. He or she also can help explain the choices that are available.

Can SCD-Related Complications Be Prevented?

SCD is a complex disease. Good quality medical care from doctors and nurses who know a lot about the disease can help prevent some serious problems. Often the best choice is a hematologist (a doctor who specializes in blood diseases) working with a team of specialists. It is also very crucial for people living with SCD to schedule regular checkups and maintain healthy living habits. Most people with SCD can live full lives and enjoy most of the activities that other people do.

The Bottom Line

Although the risk of humans contracting the avian influenza virus is low, certain precautions should be taken to reduce the risk of infection.

• SCD is a genetic condition that is present at birth. It is inherited when a child receives two sickle cell genes—one from each parent.
• SCD is diagnosed with a simple blood test. It most often is found at birth during routine newborn screening tests at the hospital.
• Because children with SCD are at an increased risk of infection and other health problems, early diagnosis and treatment are important.
• Symptoms and complications of SCD are different for each person and can range from mild to severe; there is no single best treatment for all people with SCD. Treatment options are different for each person depending on the symptoms.
• Bone marrow (stem cell) transplants are the only cure for SCD, and are used only in cases of severe SCD for children who have minimal organ damage from the disease. For the transplant to work, the bone marrow must be a close match. Usually, the best donor is a brother or sister.

Case Examples

Sam is a 15-month-old boy who was diagnosed with SCD through newborn screening. One night he starts crying for no apparent reason and cannot be comforted. His parents rush him to the hospital to see the doctor. A pediatrician notices that when Sam is crying and pulling his oxygen tubes, only one side of his body is moving. They later confirm that Sam has suffered a stroke, which is one of the serious medical conditions related to SCD. His parents later learn that this might have been prevented. Transcranial Doppler ultrasound examination can sometimes identify children with SCD who are at risk for stroke. Routine blood transfusions or an oral medication called hydroxyurea may be recommended to help prevent stroke in these children.