Red Blood Cell Indices Test – Why am I having this test?
The red blood cell indices test provides information about the cells in your blood called red blood cells (RBCs). Several different RBC characteristics are described in the test results, including:
- How much hemoglobin (Hb) each RBC contains. Hb is a protein attached to RBCs that transports oxygen throughout your body.
You may have this test as a part of a complete blood count (CBC) test. The test may also be done if you have been diagnosed with a low RBC count (anemia) and your health care provider wants to further understand what type of anemia you have.
What is being tested?
This test checks the RBCs in your blood and provides various information about them.
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 or by sticking a finger with a small needle.
Tell a health care provider about:
- All medicines you are taking, including vitamins, herbs, eye drops, creams, and over-the-counter medicines.
- Any medical conditions you have.
How are the results reported?
Your test results will be reported as values that identify various characteristics of the RBCs in your blood. Your health care provider will compare your results to normal ranges that were established after testing a large group of people (reference ranges). Reference ranges may vary among labs and hospitals. For this test, common reference ranges are:
- Mean corpuscular volume (MCV), which represents the average RBC
- Adult, elderly, or child: 80–95 fL.
- Newborn: 96–108 fL.
- Mean corpuscular hemoglobin (MCH), which represents the average
amount of Hb within an RBC:
- Adult, elderly, or child: 27–31 pg.
- Newborn: 32–34 pg.
- Mean corpuscular hemoglobin concentration (MCHC), which
represents the average concentration or percentage of Hb within an RBC:
- Adult, elderly, or child: 32–36 g/dL (or 32–36%).
- Newborn: 32–33 g/dL (or 32–33%).
- Red blood cell distribution width (RDW), which indicates the
variation in RBC size:
- Adult: 11–14.5%.
What do the results mean?
Abnormal RBC indices can indicate the following:
- Increased: pernicious anemia, folic acid deficiency, chemotherapy, alcoholism, or long-term (chronic) liver disease. In all of these, RBCs are larger than normal.
- Decreased: iron-deficiency anemia, thalassemia, or anemia of chronic illness. In these conditions, RBCs are smaller than normal.
- Increased: macrocytic anemias.
- Decreased: microcytic anemias or hypochromic anemias.
- Increased: spherocytosis, intravascular hemolysis, or cold agglutinins. In these conditions, the concentration of Hb within the RBC is higher than normal.
- Decreased: iron-deficiency anemia or thalassemia. In these conditions, the concentration of Hb within the RBC is lower than normal.
- Increased: iron-deficiency and vitamin B12-deficiency anemias, hemoglobinopathies, hemolytic anemias, or posthemorrhagic anemias. In these conditions, the width of RBCs varies.
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?
- Red blood cell indices provide information about the cells in your blood called red blood cells (RBCs).
- The test may be done if you have been diagnosed with a low RBC count (anemia) and your health care provider wants to further understand what type of anemia you have. You may also have this test as a part of a complete blood count (CBC) test.
- Abnormal RBC indices can indicate several different types of blood problems.
- Talk with your health care provider about what your test results mean.