Reticulocyte count
Anemia - reticulocyte
Reticulocytes are slightly immature red blood cells. A reticulocyte count is a blood test that measures the amount of these cells in the blood.
How the Test is Performed
A blood sample is needed.
Blood sample
Venipuncture is the collection of blood from a vein. It is most often done for laboratory testing.
How to Prepare for the Test
No special preparation is necessary.
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 slight bruise. This soon goes away.
Why the Test is Performed
The test is done to determine if red blood cells are being created in the bone marrow at an appropriate rate. The number of reticulocytes in the blood is a sign of how quickly they are being produced and released by the bone marrow.
Normal Results
A normal result for healthy adults who are not anemic is around 0.5% to 1.5%.
The normal range depends on your level of hemoglobin. Hemoglobin is a protein in red blood cells that carries oxygen. The range is higher if hemoglobin is low, from bleeding or if red cells are destroyed.
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
A higher than normal reticulocytes count may indicate:
-
Anemia due to red blood cells being destroyed earlier than normal (
hemolytic anemia
)
Hemolytic anemia
Anemia is a condition in which the body does not have enough healthy red blood cells. Red blood cells provide oxygen to body tissues. Normally, red ...
- Bleeding
- Blood disorder in a fetus or newborn (erythroblastosis fetalis)
-
Kidney disease, with increased production of a hormone called
erythropoietin
Erythropoietin
The erythropoietin test measures the amount of a hormone called erythropoietin (EPO) in blood. The hormone tells stem cells in the bone marrow to mak...
A lower than normal reticulocyte count may indicate:
- Bone marrow failure (for example, from a certain drug, tumor, radiation therapy, or infection)
-
Cirrhosis of the liver
Cirrhosis of the liver
Cirrhosis is scarring of the liver and poor liver function. It is the last stage of chronic liver disease.
- Anemia caused by low iron levels, or low levels of vitamin B12 or folate
-
Chronic kidney disease
Chronic kidney disease
Chronic kidney disease is the slow loss of kidney function over time. The main job of the kidneys is to remove wastes and excess water from the body...
Reticulocyte count may be higher during pregnancy.
Risks
There is very little risk involved with having your blood taken. Veins and arteries vary in size from one person to another and from one side of the body to the other. Taking blood 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)
References
Bope ET, Kellerman RD. Hematology. In: Bope ET, Kellerman RD, eds. Conn's Current Therapy 2016 . Philadelphia, PA: Elsevier; 2016:chap 12.
Bunn HF. Approach to the anemias In: Goldman L, Schafer AI, eds. Goldman's Cecil Medicine . 25th ed. Philadelphia, PA: Elsevier Saunders; 2015:chap 158.
Goljan EF. Red blood cell disorders. In: Goljan EF, ed. Rapid Review Pathology . 4th ed. Philadelphia, PA: Elsevier Saunders; 2014:chap 12.
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Reticulocytes - illustration
In the presence of some anemias, the body increases production of red blood cells (RBCs), and sends these cells into the bloodstream before they are mature. These slightly immature cells are called reticulocytes, and are characterized by a network of filaments and granules. Reticulocytes normally make up 1% of the total RBC count, but may exceed levels of 4% when compensating for anemia.
Reticulocytes
illustration
-
Reticulocytes - illustration
In the presence of some anemias, the body increases production of red blood cells (RBCs), and sends these cells into the bloodstream before they are mature. These slightly immature cells are called reticulocytes, and are characterized by a network of filaments and granules. Reticulocytes normally make up 1% of the total RBC count, but may exceed levels of 4% when compensating for anemia.
Reticulocytes
illustration
Review Date: 1/31/2016
Reviewed By: Laura J. Martin, MD, MPH, ABIM Board Certified in Internal Medicine and Hospice and Palliative Medicine, Atlanta, GA. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.