Reticulocytes
Last reviewed: 23.04.2024
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Reticulocytes are young forms of erythrocytes, containing a granular-filamentous substance, detected with the help of a special supripital coloration. The maturation time of reticulocytes is 4-5 days, of which within 3 days they mature in peripheral blood, after which they become mature red blood cells.
Reticulocytes are "newborns", immature erythrocytes. Reticulocytes originate in the most important organ, where actually all the new blood cells are formed, the bone marrow. It is there, as a result of the division and differentiation of stem cells, that all stages of erythrocyte maturation appear and pass.
Newborn erythrocytes contain a fragile network of microscopic blood vessels - the reticulum, from which the name of the young red corpse occurs. Emerging in the bone marrow, reticulocytes mature in it for a few more days, and then move into the blood vessels - the peripheral. There they also ripen one or two days, rapidly "growing up". It is interesting that ripe red blood cells leave a field for circulation of a small amount of reticulocytes, not more than 2%. Thus, almost in a day the "family" of red blood cells is replenished with fresh, new calves. The human body is designed so wisely that it tries to adhere to a constant pattern of erythrocyte circulation. The life of each erythrocyte lasts no more than 3 months, but due to constant partial updating the general system does not suffer. Old and worn out red blood cells are utilized by the lymphoid system, more precisely - by the spleen, and new ones - reticulocytes are born in the bone marrow every two days. There is also a kind of "dispatcher" in this continuous flow - the hormone secreted by the kidneys, erythropoietin. There is a control in this way:
When the amount of much-needed oxygen in the blood decreases, the kidney releases erythropoietin, transported by the blood flow to the "maternity home" of erythrocytes, into the main system - the bone marrow. Erythropoietin is a stimulant for the initiation of reticulocytes. If the hemopoietic organ "overdid" and the red blood cells are too many, erythropoietin ceases to be produced immediately by the kidney system.
[What is the purpose of the analysis that determines the "newborn" reticulocytes?
- First, it is an extremely important indicator of the state of the bone marrow and its regenerative capacity;
- Secondly, reticulocytes, or rather their number, show the effectiveness of therapeutic measures in different forms of anemia;
- Third, to assess and verify the function of the spleen or the functioning of the kidney after transplantation.
Also, the analysis is important for sports competitions, when participants are checked for doping.
For example, reticulocytes begin to actively push out more mature counterparts - erythrocytes, their number increases. Such activity may indicate a correct strategy in the treatment of anemia, or vice versa, the fact of blood loss in the body if therapy is not performed. Also, for quite understandable reasons, the number of "young" red blood cells rises in pregnant women.
A reduced amount of reticulocytes, as well as their disappearance, indicates a serious pathology of blood and inefficiency of therapy. The bone marrow does not cope with its functions, its condition is characterized as oppressed.
In addition, reticulocytes are an indicator of the speed of the main organ of hematopoiesis - the bone marrow.
How is the index of reticulocytes calculated?
In order to accurately assess the stage of anemia, the degree of its severity calculate the reticulocyte index by a special formula:
The percentage of reticulocytes is multiplied by the hematocrit index. Then the result is divided into the product of numbers 45 and 1.85. 45 is the level of the norm of hematocrit, and the figure 1.85 is the average period for which new reticulocytes enter the blood.
What can indicate when reticulocytes are elevated?
An increased amount of reticulocytes in medicine is called reticulocytosis. This can be a sign of diseases and problems:
- Acute loss of blood;
- Hemolytic syndrome (hemolytic anemia);
- Active therapy of thiamine-dependent anemia;
- Effective treatment of iron deficiency anemia;
- Paroxysmal infection - malaria;
- Hypoxia.
If reticulocytes are lowered, this may indicate such diseases as:
- Myelodysplasia or aplastic anemia;
- Hypoplastic pathology of the bone marrow is hypoplastic anemia;
- Ineffective treatment of megaloblastic (B12-dependent) anemia;
- Autoimmune pathologies;
- Chronic alcoholism;
- Kidney pathology.
If you have received the results of clinical blood tests and decided to independently interpret them, then at best you will simply get confused, at worst you will experience a vain alarm. Therefore, the form, where the reticulocytes and other components of the blood are described and counted, is best transferred to the reliable hands of a professional. Explain all the details will be the doctor who sent you to the study, because it was his reticulocytes that interested him.