- and what are the functions performed by
- How is the
- performed? What is the reason for the deviations from the
- ? When are
- given? Retikulonocytes in pregnancy
- . Conclusion
Reticulocytes are the precursors of red blood cells with the residues of ribonucleic acids( RNA).They circulate in the peripheral blood in a small amount. These cells are formed from normoblasts in the bone marrow, where they are about two days. Then immature red blood cells enter the blood. Under the influence of the hormone erythropoietin, which is produced by the kidneys and thrown into the blood, they become mature red blood cells. This process takes about two days.
With the acceleration of the formation of red cells, the number of reticulocytes in the blood increases, with slowing down - decreases. The mechanism of increasing reticulocytes is such that with increased destruction of erythrocytes their level can dramatically increase and make up half of all red cells. In addition, in the blood may appear precursors of reticulocytes - normoblasts.
Thus, the activity of these cells shows how fast the formation of erythrocytes is in the bone marrow. The fraction of reticulocytes in the blood reflects the properties of the bone marrow, in particular its regenerative abilities.
represents and what functions it performs. These are cell-free cells of a pinkish color with a bluish tint. At microscopic research in them intracellular structures which are not present at erythrocytes are visible. These are filamentous and granular formations: mitochondria, remnants of RNA, other organelles.
Reticulocytes perform the same functions as erythrocytes, that is, they carry oxygen, but less efficiently.
The norm of reticulocytes varies with age: in infants, their level is higher than in an adult. After 12 years, their number depends on sex. This is due to the onset of menstruation in girls and monthly blood loss.
This indicator in the total blood test is measured as a percentage of the total number of red cells( designation - RTC).The norms of reticulocytes are presented in the table:
|In women||In men|
|In newborn child||0,15-1,5||0,15-1,5|
|Up to 6 years||0,2-0,7||0.2-0.7|
|6 to 12 years||0.2-1.3||0.2-1.3|
|After 12 years||0.12-2.05||0.24-1.7|
How is the
performed? Determining the level of reticulonocytes is not included in the clinical blood test and is prescribed additionally if there is evidence. Their number is calculated by microscopic examination of the blood smear. The essence of the method is to identify cells with granular-reticulate substances that are visible when staining with special alkaline dyes.
For the analysis on reticulocytes, blood is passed from the finger
This is the simplest, affordable and low-cost method that is still used in laboratories, although it is less accurate than automatic counting. For analysis, you need a dye( use three different types), a microscope, a test tube or glass. Today they use ready-made reagents, for example, a set of Diagem. Staining on glass and in a test tube is different.
The glass is washed, dried and heated with a burner. On the glass, a drop of one of the three dyes is applied with a glass rod and a paint smear is made using a grinding glass. On the smear of the paint, a drop of blood is applied and a thin smear is made. For 5-10 minutes, put the glass in a damp chamber( usually a Petri dish, along which there are rollers of moistened cotton wool).Then the smears are dried in the air.
Staining is performed in different ways, depending on the type of dye. In general, the procedure consists in placing the paint in a test tube, adding a drop of blood to it and mixing it. The mixture is left for a while( 20 minutes to 3 hours, depending on the reagent used), then mixed again and smears are made.
Finished strokes are examined under a microscope. Erythrocytes and reticulocytes have a yellowish-greenish color, a granular structure of reticulocytes of blue or bluish-violet. The counted cells are expressed in ppm or in percent.
Species of reticulocytes on a glass in a smear after staining
For example : 20 cells with a granular mesh structure per 1000 red blood cells were detected in the smear. That is, the content of reticulocytes is 20 ppm or 2 percent.
Analysis and causes of abnormalities
If reticulocytes are lowered
If the number of red cell precursors is below normal, this means that the marrow or kidney function is impaired. With kidney disease, the level of reticulocytes will decrease slightly.
A sharp drop in these cells( even to zero) is typical for diseases that are accompanied by rapid destruction of red blood cells. This occurs with certain blood diseases, in particular with anemia:
The degree of severity of the anemia shows the reticulocyte production index, which is equal to the RCT level multiplied by the hematocrit number.
The hematopoiesis system is depleted when you abuse alcohol. Alcohol brings triple harm:
- depresses the work of the bone marrow;
- suppresses kidney function;
- alcoholic toxic substances that enter the bloodstream destroy these cells.
Activity of reticulocyte production can decrease in malignant tumors with metastases to the bone marrow, autoimmune pathologies of the hematopoiesis system, myxedema, radiation and chemotherapy.
To reduce the level of reticulocytes may lead to the taking of some drugs:
- of some antibiotics;
- antiepileptic drugs;
If reticulocytes are increased
Increasing the level of reticulocytes can be both a bad and a good sign.
The growth of these cells occurs in the following pathologies:
- oncological diseases with metastasis in the bone marrow( their level may fall, it depends on which part of the brain is affected);
- hemolytic anemia;
- oxygen starvation;
Another cause of elevated reticulocytes is significant blood loss, in which their number increases by 3-6 times. The increase in the level of these cells, on the one hand, can be considered a good sign, since this indicates the intensive formation of blood cells upon loss. On the other hand, bleeding can be a bad sign, so its causes need to be clarified and eliminated.
The following medicines increase the reticulonocytes:
- vitamin B12;
is prescribed The blood test for reticulonocytes is indicated in the following cases:
- If control of the treatment of anemia with iron and folate is required, vitamin B12.
- To control the recovery of bone marrow after its transplantation.
- If there is a suspicion of erythrocyte destruction.
- To assess the effectiveness of hematopoiesis.
Retikulonocytes in pregnancy
Pregnant women tend to have a slight increase in the content of reticulonocytes. The fact is that in future mothers the total volume of blood increases and this is not due to blood cells, but due to plasma. In "liquid" blood of pregnant women the hemoglobin level is lowered, anemia develops, so the process of hematopoiesis is activated. A slight increase in the level of reticulonocytes is considered normal and indicates a physiological adaptation, although, ideally, the number of these cells does not increase during fetal gestation.
The determination of the level of reticulonocytes is not included in the standard blood test, in which the main indicators( erythrocytes, platelets, white blood cells) are determined, and are only required if necessary. The diagnostic value of the study is mainly to assess the effectiveness of treatment of anemia.