The sickle cell test looks for the abnormal hemoglobin in the blood that causes the disease sickle cell anemia. A sickle cell test is an inherited disorder’ blood test that checks for abnormal red blood cells called sickle cells. These can cause sickle cell disease or sickle cell trait with SCD have red blood cells (RBCs) that are abnormally shaped like a crescent moon. But normal RBCs look like doughnuts or disc-shaped in shape. It affects a protein in your red blood cells that carries oxygen to your tissues. The best way to check for sickle cell trait or sickle cell disease is to look at the blood using a method called high-performance liquid chromatography (HPLC). This test identifies which type of hemoglobin is present.
How the Test is Performed
A blood sample is needed.
How the Test will Feel
When the needle is inserted to draw blood, some people feel moderate pain. Others feel only a prick or stinging. Afterward, there may be some throbbing or a bruise. This soon goes away.
Why the Test is Performed
This test is done to tell if a person has abnormal hemoglobin that causes sickle cell disease and sickle cell trait. Hemoglobin is a protein in red blood cells that carries oxygen.
In sickle cell disease, a person has two abnormal hemoglobin S genes. A person with sickle cell trait has only one of these abnormal genes and no symptoms, or only mild ones.
This test does not tell the difference between these two conditions. Another test, called hemoglobin electrophoresis , will be done to tell which condition someone has.
Normal Results
A normal test result is called a negative result.
Normal value ranges may vary slightly among different laboratories. Some labs use different measurements or test different samples. Talk to your health care provider about the meaning of your specific test results.
What Abnormal Results Mean
An abnormal test result indicates the person might have one of these:
- Sickle cell anemia
- Sickle cell trait
Iron deficiency or blood transfusions within the past 3 months can cause a “false negative” result. This means the person might have abnormal hemoglobin for sickle cell, but these other factors are making their test results appear negative (normal). Platelet count is increased. Erythrocyte sedimentation rate is low. The reticulocyte count is usually elevated, but it may vary depending on the extent of baseline hemolysis. Peripheral blood smears demonstrate target cells, elongated cells, and characteristic sickle erythrocytes.
Risks
Veins and arteries vary in size from one person to another, and from one side of the body to the other. Obtaining a blood sample from some people may be more difficult than from others.
Other risks associated with having blood drawn are slight, but may include:
- Excessive bleeding
- Fainting or feeling lightheaded
- Hematoma (blood buildup under the skin)
- Infection (a slight risk any time the skin is broken)
FAQ
What are 5 symptoms of a sickle cell crisis?
- Anemia. Sickle cells break apart easily and die.
- Episodes of pain. Periodic episodes of extreme pain, called pain crises, are a major symptom of sickle cell anemia.
- Swelling of hands and feet.
- Frequent infections.
- Delayed growth or puberty.
- Vision problems.