Sickle Cell Disease

Sickle cell disease is a heredity disorder that occurs when a person gets a defective gene for hemoglobin from both parents. (Read about "Genetics" "Birth Defects") Hemoglobin is responsible carrying the oxygen in our red blood cells. Normal red blood cells have a doughnut shaped form that is very flexible. The red blood cells of a sickle cell patient deform into what looks like a curved farm tool, called a sickle. The cells also become stiff and will clog up smaller blood vessels, causing pain and damage to surrounding tissue. The March of Dimes (MOD) says that sickle cells tend to get trapped and destroyed in the liver and the spleen. (Read about "The Spleen") The National Heart, Lung and Blood Institute (NHLBI) says sickle cells survive only 10 to 20 days in the blood stream, compared to a normal red blood cell, which survives about 120 days. The body has trouble producing enough red blood cells as a result and that leads to anemia. (Read about "Anemia")

The defective gene

NHLBI says the sickle cell gene is the result of a mutation thousands of years ago in parts of Africa, the Mediterranean basin, the Middle East and India. The mutated gene, called the sickle cell trait, gave people some protection from malaria, which was common during that time. People with the trait survived and passed the gene on to their children. Sickle cell disease happens when a person gets two sickle cell trait genes, one from each parent.

People whose ancestors come from those regions are the most likely to have the trait and/or the disease. NHLBI says that some 72,000 people in the United States are affected by sickle cell disease. The largest group is African Americans. (Read about "Minority Health") NHLBI says one in 500 births to African American parents results in sickle cell disease and that one in 12 African Americans carry the sickle cell trait, about 2 million people.

African Americans aren't the only ones affected however. NHLBI estimates between one in 1000 and one in 1400 births to Hispanic American parents results in sickle cell disease.

Testing your child

Most, but not all states test newborns for sickle cell disease, according to MOD. (Read about "Newborn Screenings") Parents who fall into the risk groups can ask for the test and even have themselves tested for the trait before a child is born. If only one parent has the trait then there is no chance the child will have the disease, but if both parents carry the trait there is a 25 percent chance the child will have sickle cell disease, according to the American Sickle Cell Association (ASCA). It is also important to remember that there is a 25 percent chance the child won't even have the trait and a 50 percent chance they will have the trait but not the disease. (Read about "Pregnancy Testing")

Dangers and complications

If a child does have sickle cell disease, they are at greater risk of many infections. (Read about "Microorganisms") The American Academy of Family Physicians (AAFP) recommends that a child with sickle cell disease may need antibiotics to prevent infections. MOD says that studies show treatment started at age 2 months and continuing for 5 years reduces the dangers of serious infections by 85 percent. AAFP and MOD also strongly urge all childhood vaccinations (Read about "Immunizations") including ones for the pneumococcal and the meningococcal bacteria. (Read about "Pneumonia" "Meningitis")

One of the greatest dangers for young children from sickle cell disease, according to MOD, is stroke. (Read about "Stroke") About 11 percent of children with the disease will suffer a stroke before the age of 20.

There are other complications of sickle cell disease, according NHLBI. They include:

• swelling of the hands and feet caused by blockage of the vessels in the extremities
• tiredness and shortness of breath, the result of anemia
• blindness can result from the lack of blood flow to the retina (Read about "The Eye")
• jaundice or a yellowing of the skin and eyes, which is the result of the quick death of red blood cells (Read about "Jaundice")
• pulmonary hypertension ((Read about "Pulmonary Hypertension")
• slow growth in children or delayed puberty (Read about "Child Development") and a slight build in adults

Males with sickle cell disease may experience prolonged, often painful erections, a condition called priapism. Long-term erections can result in damage and need to be treated.

NHLBI also lists acute chest syndrome as a life threatening complication. It is similar to pneumonia and is caused by sickle cells trapped in the lungs.

Crisis episodes

Pain or crisis episodes are the most common symptom of sickle cell disease. When the damaged sickle cells pile up in a blood vessel, they block the flow of the blood and oxygen getting to that part of the body. The result is pain. MOD says most of the time it occurs in the bones. Usually it is impossible to tell exactly what triggers a sickle cell crisis but AAFP has some suggestions to perhaps lessen their occurrence:

• do not smoke (Read about "Quit Smoking")
• do not drink alcohol
• do drink at least 8 glasses of water a day and more fluids when exercising
• dress warmly in cold weather or in cool air conditioning and avoid swimming in cold water
• get appropriate exercise; speak to your doctor before starting any exercise program
• reduce your stress levels (Read about "Stress")

Some crisis episodes require hospitalizations; minor ones are sometimes handled at home. Doctors will use various painkillers depending on the severity of the episode. Hydroxyurea is a drug that can help to prevent painful crises from occurring, according to the Food and Drug Administration (FDA). Ask your doctor.

The future

There is no easy cure for sickle cell disease. Blood transfusions can help reduce some of the complications, particularly for children, according to AAFP. But too many transfusions can lead to a dangerous build-up of iron in the body. There are a limited number of drugs that can help reduce pain and other symptoms of sickle cell disease. Bone marrow transplants (Read about "Transplants") have been successful in curing some cases, according to MOD, but transplants are risky and not always successful.

Because of progress in medical care and early intervention, MOD says sickle cell disease is better managed for many patients. This has translated into an increase in life expectancy, according to NHLBI. New treatments, such as gene therapy may hold more promise for the future.

Related Information:

    Healthy Pregnancy

    Pregnancy Testing

    Chronic Pain

    Vascular System