The goals of sickle cell tests are to diagnose sickle cell anemia as soon as possible, to identify people with sickle cell trait, and to identify, evaluate, and treat complications as they arise. Newborn screening for sickle cell is now performed routinely throughout the U.S. This testing can identify the specific types of hemoglobin present in a newborn using a few blood drops collected via heel stick.
Sickle cell tests include:
- Hemoglobin solubility test and sodium metabisulfite test to screen for sickle cell anemia
- Hemoglobinopathy (Hb) evaluation through hemoglobin electrophoresis, hemoglobin isoelectric focusing, or HPLC to detect abnormal types and measure relative amounts of hemoglobins present in the red blood cells (RBCs); the test may also be performed after a blood transfusion to ensure that a sufficient amount of normal hemoglobin is present to reduce the risk of damage from RBC sickling.
- Genetic testing—DNA analysis to investigate mutations in the genes that encode hemoglobin components(beta-globin); DNA testing can also be used to determine if a person is a carrier for sickle cell anemia. This genetic testing (screening) can also be carried out prenatally, either by evaluating cell-free fetal DNA isolated from maternal circulation or by analyzing the DNA of the fetal cells isolated from amniotic fluid via amniocentesis.
Other tests may include:
- Complete blood count (CBC) to determine the number and average size of RBCs in the body as well as how much hemoglobin they contain, both of which are often low in those with sickle cell disease
- Blood smear (also called peripheral smear and manual differential) to screen for abnormal-looking and sickle-shaped RBCs
- Iron studies to evaluate the body's level of iron, which can be increased in sickle cell patients who have received multiple blood transfusions
- Bilirubin is used for evaluating individuals with jaundice and suspicion of gallstones, as well as a an additional test for evaluation of hemolytic anemia.
- Creatinine test to detect increased levels of creatinine in the blood that indicate abnormal kidney function in order to monitor for the development of kidney disease