How Donating Blood Could Increase Reticulocytes Numbers

At a Glance

Why Go Tested?

To aid your health care practitioner evaluate your bone marrow's ability to produce red blood cells (RBCs); to help distinguish between various causes of anemia; to assist monitor bone marrow response and the return of normal marrow function post-obit chemotherapy, bone marrow transplant, or post-treatment follow-up for iron deficiency anemia, vitamin B12 or folate deficiency anemia, or renal failure

Sample Required?

A blood sample is collected by inserting a needle into a vein in your arm or sometimes from a fingerstick or heelstick (babe).

Test Preparation Needed?

None

What is being tested?

Reticulocytes are newly produced, relatively immature red blood cells (RBCs). A reticulocyte count helps to determine the number and/or percentage of reticulocytes in the blood and is a reflection of recent bone marrow function or action.

Cherry claret cells are produced in the bone marrow, where blood-forming (hematopoietic) stem cells differentiate and develop, eventually forming reticulocytes and finally condign mature RBCs. Reticulocytes are visually, slightly larger than mature RBCs. Unlike most other cells in the body, mature RBCs have no nucleus, but reticulocytes still have some remnant genetic fabric (RNA). Equally reticulocytes mature, they lose the last balance RNA and near are fully developed within one twenty-four hour period of beingness released from the os marrow into the blood. The reticulocyte count or percentage is a skillful indicator of the ability of a person's bone marrow to adequately produce red blood cells (erythropoiesis).

RBCs typically survive for virtually 120 days in apportionment, and the bone marrow is continually producing new RBCs to supervene upon those that historic period and dethrone or are lost through haemorrhage. Usually, a stable number of RBCs is maintained in the blood through continual replacement of degraded or lost RBCs.

A diverseness of diseases and atmospheric condition can affect the production of new RBCs and/or their survival, in add-on to those conditions that may result in meaning bleeding. These weather condition may lead to a ascent or drop in the number of RBCs and may touch the reticulocyte count.

Higher than normal percent of reticulocytes: Acute or chronic bleeding (hemorrhage) or increased RBC destruction (hemolysis) tin can lead to fewer RBCs in the claret, resulting in anemia. The body compensates for this loss or to handling of deficiency anemias (such every bit fe deficiency anemia or pernicious anemia) past increasing the rate of RBC product and past releasing RBCs sooner into the blood, earlier they become more mature. When this happens, the number and percentage of reticulocytes in the blood increases until a sufficient number of RBCs replaces those that were lost or until the production capacity of the bone marrow is reached.

Lower than normal percent of reticulocytes: Decreased RBC production may occur when the bone marrow is not operation commonly. This tin can result from a bone marrow disorder such every bit aplastic anemia. Diminished production tin can also be due to other factors, for instance, cirrhosis, kidney disease, radiation or chemotherapy treatments for cancer, a low level of the hormone erythropoietin, or deficiencies in certain nutrients such as iron, vitamin B12 or folate. Decreased production leads to fewer RBCs in circulation, decreased hemoglobin and oxygen-conveying capacity, a lower hematocrit, and a reduced number of reticulocytes as old RBCs are removed from the claret but non fully replaced.

Occasionally, both the reticulocyte count and the RBC count will be increased considering of excess RBC product by the os marrow. This may be due to an increased production of erythropoietin, disorders that cause chronic overproduction of RBCs (polycythemia vera), and cigarette smoking.

Some drugs may increase or decrease reticulocyte counts.

Common Questions

How is the exam used?

A reticulocyte count is used to determine the number and/or per centum of reticulocytes in the blood to assistance evaluate weather that touch on blood-red blood cells (RBCs), such as anemia or os marrow disorders. Reticulocytes are newly produced, relatively young red blood cells. They grade and mature in the os marrow earlier being released into the blood.

The reticulocyte count may be used:

As a follow up to abnormal results on a complete blood count (CBC), RBC count, hemoglobin or hematocrit, to aid determine the crusade
To decide if the bone marrow is functioning properly and responding adequately to the body's need for red blood cells
To help observe and distinguish between dissimilar types of anemia
To monitor response to treatment, such as that for atomic number 26-deficiency anemia
To monitor bone marrow function following treatments such as chemotherapy
To monitor function following a bone marrow transplant

Most often, a reticulocyte count is performed with an automatic instrument (hematology analyzer) and tin be washed simultaneously with a CBC, which includes an RBC count, hemoglobin and hematocrit. Either an accented number of reticulocytes and/or a percentage of reticulocytes can be reported. For a pct, the number of reticulocytes counted manually is compared to the total number of RBCs:

Reticulocyte (%) = number of reticulocytes 10 100 / 1000 (RBCs counted)

For healthcare providers who want to have a definitive number of reticulocytes, they can order an Absolute Reticulocyte Count (ARC):

ARC = reticulocytes (%) x RBC count (x 1012/50) / 100

When is it ordered?

A reticulocyte count may be ordered when:

CBC results evidence a decreased RBC count and/or a decreased hemoglobin and hematocrit
A health care practitioner wants to evaluate bone marrow function
Y'all have signs and symptoms of anemia or chronic bleeding, such as paleness, lack of free energy, fatigue, weakness, shortness of breath, and/or blood in the stool
You have been diagnosed and are being treated for a condition known to affect RBC production, such as iron deficiency anemia, vitamin B12 or folate deficiency, or kidney disease (which tin can affect the production of erythropoietin, a hormone produced by the kidneys that stimulates RBC production by the bone marrow)
You are undergoing radiation or chemotherapy
You have received a bone marrow transplant
Occasionally when you take an increased number of RBCs and elevated hemoglobin and hematocrit, to help decide the degree and rate of overproduction of RBCs

What does the test upshot mean?

Results must be interpreted advisedly and along with results of other tests, such as a reddish blood cell (RBC) count, hemoglobin (Hb), hematocrit (Hct), or full CBC. In general, the reticulocyte count (absolute number or percentage) is a reflection of recent os marrow activity. Results may bespeak whether a illness or status is present that is generating an increased demand for new RBCs and whether the bone marrow is able to respond to the extra requirement. Occasionally, results may indicate overproduction of RBCs.

When anemia is nowadays (i.e., depression RBCs, low hemoglobin, depression hematocrit) and the bone marrow is responding appropriately to the demand for increased numbers of RBCs, and then the bone marrow will produce more and allow for the early on release of more than immature RBCs, increasing the number of reticulocytes in the blood.

A high reticulocyte count with depression RBCs, low hemoglobin, and low hematocrit (anemia) may indicate weather condition such every bit:

Bleeding: If you lot bleed, and so the number of reticulocytes will rise a few days afterward in an attempt to recoup for the scarlet cell loss. If you lot have chronic claret loss, then the number of reticulocytes will stay at an increased level every bit the marrow tries to keep upwards with the demand for new RBCs (although it may non be high if the blood loss leads to atomic number 26 deficiency).
Hemolytic anemia: In this condition, anemia is caused by increased destruction of RBCs. The bone marrow increases RBC product to compensate, resulting in a high reticulocyte count.
Hemolytic illness of the newborn: This condition causes increased RBC devastation, similar to hemolytic anemia described above.

A low reticulocyte count with low RBCs, low hemoglobin, and low hematocrit (anemia) may be seen, for instance, with:

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 crusade a low level of erythropoietin.
Alcoholism

When you have anemia, the pct of reticulocytes nowadays in the blood may appear high compared to the overall number of RBCs. In society to get a more than accurate assessment of bone marrow function, a calculation called a corrected reticulocyte count may be reported.

Corrected reticulocyte count (%) = reticulocyte (%) x [patient HCT(%)/45]
45 is considered the boilerplate normal hematocrit (HCT).

Other calculations that may also be reported include the reticulocyte production index (RPI) and an immature reticulocyte fraction (IRF). The IRF was previously referred to as the reticulocyte maturity index; however, IRF is now the about common term used to quantify the younger fraction of reticulocytes.

The reticulocyte test gives an indication of the presence of a disease or condition just is not directly diagnostic of whatsoever one particular disease. It is a sign that further investigation may be necessary and a tool that can exist used to monitor the effectiveness of therapy.

If reticulocyte numbers rise following chemotherapy, a bone marrow transplant, or treatment of an iron or vitamin B12 or folate deficiency, then os marrow RBC production is get-go to recover.

When you do not have anemia, or have a loftier RBC count (polycythemia), a loftier reticulocyte count may indicate an overproduction of RBCs. Some conditions that may cause this include:

Polycythemia vera
Tumor that produces backlog erythropoietin

In add-on to a reticulocyte count, what other tests may be done?

Several other tests may be used in conjunction with a reticulocyte count to further evaluate someone for a condition affecting RBC production. Some examples include:

Iron studies
Vitamin B12 and Folate
Haptoglobin
G6PD
Erythropoietin

Sometimes a bone marrow aspiration and biopsy may be done in follow up to abnormal results on initial tests. This procedure is invasive and can not be performed on everyone. It tin can, yet, provide boosted information, if necessary.

What is a corrected reticulocyte count (CRC)?

When you accept anemia (the number of red claret cells (RBCs), hemoglobin and hematocrit are low), the percentage of reticulocytes may announced high compared to the overall number of RBCs. This is in part due to the immature cells' early on release from the bone marrow into circulation and the longer time they spend maturing in the claret (from the normal ane day to three or 4 days). In club to get a more accurate assessment of os marrow function, the reticulocyte pct (%) is oftentimes corrected with a calculation chosen a corrected reticulocyte count (CRC). This calculation compares your hematocrit with a normal hematocrit value.

What is a reticulocyte production index (RPI)?

The reticulocyte production index (RPI) is a calculation to correct for the degree of reticulocyte immaturity, reflecting how early the reticulocytes were released from the os marrow and how long it will have them to mature in the bloodstream. The RPI and maturation time vary with the hematocrit.

Reticulocyte Production Index = corrected reticulocyte count/maturation fourth dimension

The maturation fourth dimension is based on a patient'south hematocrit with correction factors varying from the typical i day to as much as three days.

What is immature reticulocyte fraction (IRF)?

The immature reticulocyte fraction (IRF) is calculated equally a ratio of young reticulocytes to the full number of reticulocytes. It is reported past an automated blood analyzer when a reticulocyte count exam is performed. In sure conditions, IRF is a better indicator of bone marrow response than a total reticulocyte count.

My consummate blood count (CBC) written report includes a outcome for reticulocyte hemoglobin. What is it?

The hemoglobin inside of reticulocytes can be measured and reported as either a mean reticulocyte hemoglobin content (CHr) or a reticulocyte hemoglobin equivalent (Ret-He), depending upon the examination method used. This test result would be one of the values reported when blood is evaluated using an automated hematology analyzer.

Reticulocytes are "immature" crimson blood cells that are released by the bone marrow earlier they become fully mature. The amount of hemoglobin inside of reticulocytes can help determine if there has been enough iron available, to exist incorporated into hemoglobin production and and so into red blood cell production in the bone marrow, within the by few days. This makes the test useful in identifying functional iron deficiency in certain clinical weather and in assessing iron deficiency anemia in children.

Tin can the reticulocyte count exist done on the same tube of blood as the RBC count or CBC?

Yeah. If anemia is detected during a routine claret test, the health care practitioner may order additional testing (including a reticulocyte count) on the same tube of blood if it tin be done on the aforementioned day.

Will a blood transfusion impact reticulocyte results?

Aye. Your health care provider will determine how long you should wait after a transfusion before having a reticulocyte count performed.

How else might my physician evaluate the cell product in my os marrow?

In some cases, a procedure called a os marrow aspiration may be performed to obtain a sample of marrow to evaluate under the microscope. Sometimes this is the all-time manner for a health care provider to determine how well the os marrow is operation.

Is in that location anything else I should know?

People who move to higher altitudes may accept slightly higher reticulocyte counts for a while equally their trunk adapts to the lower oxygen content of their new location. Smokers also may demonstrate an increased number of RBCs and reticulocytes.

Reticulocyte counts may be high during pregnancy. Newborns have a higher pct of reticulocytes, only the number drops to near adult levels within a few weeks of nascence.

Traditionally, reticulocyte counts have been washed manually by looking at a especially stained slide under the microscope and counting the number of reticulocytes in a number of fields of view. Although information technology is used occasionally, the manual method has been replaced past automated methods that let for a greater number of cells to be counted, thus enhancing the accuracy of reticulocyte counts. The automated method is considered to exist more than authentic in identifying reticulocytes.

View Sources

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