What is Sickle Cell Testing

Sickle cell testing is used to determine if you have:

• Sickle cell anemia. This is a condition in which red blood cells have an abnormal “sickle” shape. Red blood cells carry oxygen through the body. Sickle-shaped red blood cells do not live as long as normal red blood cells. They also clump together and block blood from flowing through the blood vessels.
• The sickle cell trait. Sickle cell anemia is caused by a gene that is passed from parent to child (inherited). Having two copies of the gene causes the disease. Having one copy causes the “trait,” which means that you may have no symptoms or milder symptoms but could pass the trait to a child.

Newborns have sickle cell testing as part of routine testing that is done at the hospital after birth (newborn metabolic screening).

You may have this test if you have symptoms of sickle cell disease and:

• Your ancestors were from Africa, the Mediterranean, South or Central America, the Caribbean, India, or the Middle East. This raises the risk for sickle cell anemia.
• You had abnormal results from a different blood test, such as a complete blood count (CBC) test.

What is being tested?

This test checks the blood for the presence of hemoglobin S (HbS). Hemoglobin is a protein in red blood cells that binds to oxygen, so that oxygen can be delivered throughout the body. HbS is an abnormal form of hemoglobin associated with sickle cell disease.

What kind of sample is taken?

A blood sample is required for this test. It is usually collected by inserting a needle into a blood vessel.

How do I prepare for this test?

Follow instructions from your health care provider about changing or stopping your regular medicines before the test.

How are the results reported?

Your test results will be reported as either positive or negative. Positive means that there is HbS in your blood. Negative means that there is no HbS in your blood.

What do the results mean?

A negative test result means that you most likely do not have sickle cell trait or sickle cell disease.

A positive test result means that you have either the sickle cell trait or sickle cell disease.

Talk with your health care provider about what your results mean.

Questions to ask your health care provider

Ask your health care provider, or the department that is doing the test:

• When will my results be ready?
• How will I get my results?
• What are my treatment options?
• What other tests do I need?
• What are my next steps?

Summary

• Sickle cell testing is used to determine if you have sickle cell trait or sickle cell disease.
• Sickle cell anemia is caused by a gene that is passed from parent to child (inherited). Having two copies of the gene causes the disease. Having one copy causes the “trait,” which means that you may have no symptoms or milder symptoms but could pass the trait to a child.
• A negative result means that you most likely do not have sickle cell trait or sickle cell disease.
• A positive result means that you have either the sickle cell trait or sickle cell disease.