Reticulocyte - what is it in a blood test? Norm indicators and designation
Reticulocyte is the precursor of the erythrocyte, that is, it is the erythrocyte in a young form. In the blood of a healthy person, their content is 0.2-1.2%. This ratio reflects the content of reticulocytes in the blood relative to the erythrocytes. They mature 4-5 days.
A characteristic feature of the young forms of red blood cells - in the cytoplasm there is a granular-filamentous substance, which is an aggregated ribosome and mitochondria. Identify this substance can be using a special method of staining blood smears. This color of reticulocytes is called supravital, that is, it is made without prior fixation of the cells.
In total, experts identify five main groups of reticulocytes. They differ in reticular reticulum. Her density and age are in inverse proportionality: the thicker the mesh, the younger they are. We will understand what is the youngest reticulocyte.
This is a cell that has a reticulum in the form of a thick coil. These cells belong to the first group. Reticulocytes of a more mature form are manifested in the form of a substance that has a clearly distinguishable reticulum. In the fourth and fifth group, it is represented by individual threads and grains. Most often, the blood of healthy people contains the reticulocytes of the latter group, that is, more mature. As a rule, they make up about 80% of the rest. With enhanced regeneration, which is characteristic of some pathologies, the number of reticulocytes of the first three groups increases. These pathologies include:
• Reticulocyte crisis accompanying B12-deficient anemia.
• Hemolytic anemia.
The functions that perform reticulocytes
Reticulocyte is also an erythrocyte. It is characterized by the same function as for erythrocytes. That is, the cells also transfer oxygen molecules to different tissues and organs, but the effectiveness of this process is much lower than when oxygen is transferred by mature erythrocytes. Reticulocytes can adsorb iron molecules that are contained in hemoglobin.This is possible due to receptors susceptible to transferrin. Why do they count reticulocytes? About it further.
Mechanism of blood sampling
A blood sample is taken for the determination of this indicator as part of a general analysis. If there is a need to determine the level of reticulocytes, then the doctor who prescribed the analysis points in the direction of the need for additional counting.
This analysis does not require special preparation, but traditionally it is given on an empty stomach in the morning. At the same time, if there is a need, it can be handed over at any time of the day. Blood for analysis should be taken from the finger, its research is carried out in the laboratory, in the hematology department.
The count of the number of reticulocytes is carried out in a supravital stained smear. The microscopic method is used, that is, their number is simply counted by placing a blood sample under a microscope. To date, there is a hardware method of counting. Use its modern laboratories.
The designation of reticulocytes in the blood test - RET.
There are several methods for conducting such a study:
- The glass is washed, dried and heated with a special burner. Next, one of the three dyes is applied to it, then a drop of blood is added, after which a thin smear is made. Place the glass in a Petri dish or another chamber for a certain time, then dry it in fresh air.
- If a test tube is used, a colorant is placed in it, and a drop of blood is also added there. The mixture must be mixed. Waiting time - from 20 minutes to 3 hours, it depends on which reagent is used. Then again mix the liquid that is in the tube, take strokes from it.
Which method determines the more accurate results is difficult to say. Both of them are good in their own way, but the doctor may consider it necessary to conduct the analysis in a certain way, then he should point it in the direction.
When calculating the level of reticulocytes, sexual differences of the norm are important only after 12 years. Until this age, the norm in children of both sexes is the same. At the age of about 11-12 years, girls begin to have menstruation, which is regular. As a result of monthly blood loss, the range of erythroid cell oscillations expands.
So, the rate of reticulocytes in the blood:
1. In newborns, the rate is in the range from 0.15 to 1.5%.
2. In children aged two weeks - from 0.45 to 2.0%.
3. In children aged one to two months - from 0.25 to 0.95%.
4. In children at the age of six months - from 0.2 to 1.0%.
5. In children aged two to six years - from 0.25 to 0.75%.
6. In children aged six to twelve years - from 0.25 to 1.3%.
7. In men older than twelve years - from 0.25 to 1.7%.
8. In women older than twelve years - from 0.12 to 2.1%.
What does it mean when reticulocytes are elevated?
The increase in the number of reticulocytes in the blood
With anemia of various etymologies, the determination of the number of reticulocytes plays a special role. If their blood levels are elevated, then this pathology is called reticulocytosis. If the increase is accompanied by an increase in hemoglobin level, then this suggests that the bone marrow has good regenerative capacity. This can occur if the following factors are present:
• Hemolytic anemia of different etymologies. It is a series of diseases that are characterized by the destruction of red blood cells. This phenomenon is called hemolysis. In this case, the content in the blood of reticulocytes can reach 60%. If a hemolytic crisis occurs, this figure may be exacerbated.
• Hematoxin poisoning, causing hemolysis. To hemotoxins can be attributed the venom of the adder and some medications that are used to treat erythremia. Malaria toxins can also cause hemolysis.
• Therapy "Levodopa" in Parkinson's disease.
• Long-term use of certain anti-inflammatory and antipyretic drugs.
• Therapy with the drug “Erythropoietin” of anemic diseases.
• Bone marrow metastases.
• Recovery period after radiation or chemical therapy.
• Post-hemorrhagic anemia.
Reticulocytosis can be false and true.
Why test for reticulocytes? This question is often asked.
False and true reticulocytosis
True reticulocytosis is characterized by an increase in the number of young reticulocytes in the blood, which is accompanied by an increase in their number in the bone marrow.
A false reticulocytosis is characterized by an increase in the number of reticulocytes exclusively in peripheral blood, while in the bone marrow their level remains normal or slightly reduced.
The process of reducing the number of reticulocytes is observed in the inhibition of erythropoiesis. Occurs as a result of the following factors:
• Long-term use of sulfonamides.
• Taking certain medications, such as chloramphenicol or carbamazepine.
• Development of uremia.
• Chronic infectious diseases.
• Severe alcoholism.
• Some severe kidney diseases affecting erythropoiesis.
• Myxedema or other thyroid dysfunction.
• Tumors in the bone marrow.
• Sedroblastnaya anemia.
• Folic acid deficiency anemia.
• Iron-deficiency anemia.
• B12-deficient anemia.
• Allastic anemia.
We considered what is reticulocyte. This is a young red blood cell in human blood.