Reticulocyte Count
Also known as
Retic Count, Reticulocyte Percent, Reticulocyte Index, Corrected Reticulocyte, Reticulocyte Production Index, RPI
This test is ordered by your doctor when he or she wants to evaluate your bone marrow's ability to produce healthy red blood cells. It helps in distinguishing between different causes of anemia and aids in analyzing and monitoring bone marrow response. It also helps monitor the bone marrow function post-chemotherapy, bone marrow transplant, and after the treatment, follows up for iron-deficiency anemia, vitamin B12 or folate deficiency anemia, or renal failure.
The test is ordered when the results of a complete blood count test indicate that the patient has a low red blood cell count, hemoglobin (the protein responsible for carrying oxygen around the body), and hematocrit (the proportion of blood which is made up of red blood cells). It is also ordered when patients show signs of anemia and when the doctor needs to evaluate bone marrow function.
This is a blood test. A blood sample is collected via a syringe needle inserted into the arm.
There is no preparation needed for the test.
Reticulocytes are the newly made, somewhat immature red blood cells that are released into the bloodstream. The reticulocyte count aids the doctor in measuring the amount or percentage of the new red blood cells. The count reflects the quality of bone marrow function in the body. Red blood cells are made by the bone marrow. In the bone marrow, blood-forming stem cells differentiate and develop into reticulocytes which further develop into red blood cells (RBC). Reticulocytes are minimally larger than mature red blood cells. Mature red blood cells have no nucleus, but reticulocytes have some strands of RNA, a genetic material. When they become fully mature, they lose the RNA. They fully mature one or two days after they have been released by the bone marrow into the bloodstream. The reticulocyte count reflects the ability of the bone marrow to perform its function optimally – it indicates whether it is producing an adequate amount of red blood cells or not. Red blood cells have a lifespan of 120 days in circulation. The bone marrow's job is to constantly reproduce and replenish red blood cells, which age, degrade, or are lost through bleeding. In a healthy individual, a stable number of red blood cells are maintained in the bloodstream through continual replenishment. The production of red blood cells is detrimentally impacted by a number of conditions and diseases. Their survival is also contingent on these. Some conditions may also lead to heavy bleeding. These conditions may also cause an increase or decrease in the number of red blood cells, and it may also impact the reticulocyte count. The test is used by the doctor to evaluate bone marrow function. Low or high reticulocyte count indicates something awry in bone marrow function. When an individual experiences acute or chronic bleeding, or hemolysis (red blood cell destruction), it can lead to fewer red blood cells in the blood, resulting in anemia. In this situation, the body reacts by increasing the rate of red blood cell production and releasing a steady flow of slightly immature red blood cells sooner into the bloodstream. Therefore, the number and percentage of reticulocytes in the blood increases until the adequate number of red blood cells replaces the ones that were lost. On the other hand, lower reticulocyte counts occur when the bone marrow fails to function properly. This can happen due to a bone marrow disorder like aplastic anemia. It can also happen due to occurrences like cirrhosis of the liver, kidney diseases, radiation, chemotherapy, or deficiencies in nutrients like iron, folate, or vitamin B12. Less production of reticulocyte counts can lead to fewer red blood cells in circulation, less hemoglobin which leads to less oxygen-carrying capacity, a lower number of red blood cells in the blood overall, and a low number of new red blood cells when the old ones are not replenished. Sometimes, the reticulocyte count and the red blood cell count may be higher than normal because of the production of red blood cells in excess by the bone marrow. This can be due to erythropoietin or other chronic disorders.
The reticulocyte count is used for a number of things. It is used as a follow-up to abnormal results on a complete blood count (CBC), RBC count, hemoglobin, or hematocrit in order to help determine the cause. It helps evaluate if the bone marrow is functioning properly and responding adequately to the body's need for red blood cells. Furthermore, it helps differentiate and identify different types of anemia. It helps evaluate the response of the patient to treatment, such as that for iron-deficiency anemia. It also helps in monitoring bone marrow function after treatments like chemotherapy and gauges the healthy function of bone marrow after a transplant.
The test is ordered in a variety of circumstances:
- When the complete blood cell count results indicate a lower amount of RBC count and/or less hemoglobin and hematocrit
- To evaluate bone marrow function
- When the patient shows signs and symptoms of anemia or chronic bleeding, such as paleness, lack of energy, fatigue, weakness, shortness of breath, and/or blood in the stool
- If the patient has a condition that impacts red blood cell production like iron deficiency anemia, vitamin B12 or folate deficiency, or kidney disease
- If the patient is undergoing radiation or chemotherapy
- If the patient has had a bone marrow transplant
The doctor must interpret the results in conjunction with other tests, such as a red blood cell (RBC) count, hemoglobin (Hb), hematocrit (Hct), or full CBC. The results of this test indicate recent bone marrow function and allude to whether a disease or condition is present in which there is an increased demand for new red blood cells, and the bone marrow is fulfilling it. A high reticulocyte count with low RBCs, low hemoglobin, and low hematocrit (anemia) may indicate conditions like bleeding, hemolytic anemia, or hemolytic disease of the newborn. A low reticulocyte count with low RBCs, low hemoglobin, and low hematocrit (anemia) may be seen in conditions like iron deficiency anemia, pernicious anemia or folic acid deficiency, aplastic anemia, radiation therapy, bone marrow failure caused by infection or cancer, severe kidney disease; this may cause a low level of erythropoietin, alcoholism, and endocrine disease.
Frequently ordered together
Vitamin B12
CBC (includes Differential and Platelets)
Hematocrit HCT
Hemoglobin Hb
Iron
Red Blood Cell RBC Count
Vitamin B12 and Folic Acid
HEMOGLOBIN AND HEMATOCRIT-HGB and HCT
IRON TOTAL and Iron Binding Capacity IBC
Iron Studies
HEMOGRAM
Iron Total and Total Iron Binding Capacity TIBC (Reflex)
CBC (HH-RBC-WBC-PLT)
25.00$
18.00$
12.00$
12.00$
16.00$
13.00$
40.00$
15.00$
25.00$
39.00$
14.00$
16.00$
16.00$
