Does this test have other names?
Reticulocyte (reh-TICK-you-loh-SITE) count, retic
What is this test?
This test measures the number of reticulocytes in your blood.
Reticulocytes are immature red blood cells that are still developing. The test finds out whether the marrow inside your bones is making red blood cells the way it should.
Red blood cells flow throughout your bloodstream, bringing in fresh oxygen and taking away carbon dioxide. If your body doesn't make enough red blood cells, you may have a condition called anemia.
You may have anemia if your body doesn't have enough iron. This causes a condition called iron-deficiency anemia. You may also have anemia if you have kidney disease or a blood disease such as thalassemia, which affect your body's ability to make red blood cells.
This test can be used to diagnose anemia and find out why you have a disease. The test can also help figure out how serious the disease is.
Why do I need this test?
You may need this test if your doctor suspects that you have anemia. The signs and symptoms of anemia may include:
Feeling weak and quite tired
Headaches, feeling short of breath, or chest pain
Cracks in your mouth
Swelling of your tongue
Feeling cold or numb in your hands or feet
Getting sick often
Craving nonfood substances such as dirt or starch, a condition called pica
What other tests might I have along with this test?
Your doctor may also order other tests, including:
Complete blood count, or CBC, to measure other substances in the blood, including hematocrit, white blood cells, platelets, and hemoglobin
Blood tests to measure the levels of iron in your blood
Tests to measure the levels of hormones, including thyroid hormones, in your blood
Fecal occult blood test, to check for internal bleeding
Children may have tests to measure the levels of lead in their blood.
What do my test results mean?
Many things may affect your lab test results. These include the method each lab uses to do the test. Even if your test results are different from the normal value, you may not have a problem. To learn what the results mean for you, talk with your health care provider.
Results are given as a percentage. The normal level of reticulocytes in the blood is between 0.5 and 1.5 percent. If your result is 4 percent or higher, you may have anemia.
How is this test done?
The test requires a blood sample, which is drawn through a needle from a vein in your arm.
Does this test pose any risks?
Taking a blood sample with a needle carries risks that include bleeding, infection, bruising, or feeling dizzy. When the needle pricks your arm, you may feel a slight stinging sensation or pain. Afterward, the site may be slightly sore.
What might affect my test results?
Other factors aren't likely to affect your results.
How do I get ready for this test?
You may need to avoid eating or drinking anything but water before your test. Be sure your doctor knows about all medicines, herbs, vitamins, and supplements you are taking. This includes medicines that don't need a prescription and any illicit drugs you may use.