It is known that the blood consists of the liquid part( plasma) and the shaped elements( erythrocytes, platelets and leukocytes).In the human body, there is nothing unnecessary. The norm of leukocytes in blood, as well as of other cells, depends on various factors, is limited by certain digital boundaries. The number of white blood cells is different in the morning and evening, before and after meals, in a small child and in old age. Significant fluctuations are found during pregnancy.
To determine which norm of leukocytes is valid in a particular area, statistical analysis of general blood tests of healthy people of different ages is carried out. The average level of leukocytes is taken as normal.
How are the varieties of leukocytes counted?
Leukocytes, unlike erythrocytes and platelets, are not colored, but have an intracellular nucleus and can move, performing amoeboid movements. They are capable of pushing other elements of blood, squeezing through the wall of the capillary to the focus of inflammation.
Counting the number of leukocytes are provided by laboratory assistants in the clinical departments of laboratories in polyclinics and hospitals. The analysis is taken in the morning on an empty stomach from a finger. A special scarifier is pierced with a skin and a few drops of blood are sucked off with a pipette and a pear.
The total content of leukocytes is determined by the apparatus. And their species are considered under a microscope. As a result, the figure is indicated, followed by the "x109 / l" icon. Ten in the ninth degree means "nine zeros" or "the number of billions of cells" in a liter of blood.
Species of leukocytes
Two kinds of leukocytes are distinguished in the cytoplasm of granule cells( granularity):
- granulocytes( neutrophils, eosinophils, basophils);
- agranulocytes( monocytes, lymphocytes).
For the diagnosis, the doctor needs to know not only the total level of leukocytes in the blood, but also the percentage of different cells. Such an analysis is called the definition of the leukocyte formula or decoding of the data. Normally it looks like this:
- contains 40 - 75% of neutrophils;
- 20 - 45% of lymphocytes;
- 3 - 8% of monocytes;
- up to 5% of eosinophils;
- up to 1% of basophils.
All cells are produced in lymph nodes, bone marrow and spleen. Lymphocytes are contained in lymphatic vessels. Neutrophils are also called "phagocytes" for their ability to digest foreign microorganisms. Some cells retained their name for their kinship with certain coloring substances.
Blue leukocyte, able to move, thanks to its processes
is schematically shown. What is involved in the leukocytes
The main role of leukocytes is participation in protecting the body from any infection. They accumulate around the bacterium or virus, surround it from all sides, macrophages envelop and neutralize the foreign agent. After this, the leukocytes are destroyed. If they are not able to neutralize a large number of infections, they form a protective barrier. Pus in the wound is an infection, along with an abundance of dead blood cells.
The functions of leukocytes in the immune reaction have been sufficiently studied. It is established that they are subdivided into killer cells that kill bacteria, cells that transmit signals from the nervous system about the beginning and end of the reaction, cells that retain information about the obtained experience and transmit it to the new leukocytes.
Normal level and its changes
Decoding of the blood test at the MNO
The norms of the number of leukocytes for newborns range from 9 to 30 x109 / l. In adults, they drop to 4-9 x 109 / l. In the blood should be as many leukocytes as necessary to fully match the physiological state. It is considered the norm to increase during pregnancy, after eating and exercise, overheating or cooling.
The growth of the total number of three or more times can be explained only by some disease. There are terms adopted to denote the leukocyte reaction in the blood: leukocytosis - excess of leukocyte content is higher than normal, leukopenia - on the contrary, decrease. In this case, there is no uniform growth or decrease in all types of leukocytes. According to the changed leukocyte formula, we can assume the type of pathogen.
Most often, leukocytosis is determined in the presence of inflammation in the internal organs( in the lungs, urinary system, in the first days after myocardial infarction).By the size it is possible to judge the nature of the inflammatory reaction. Suppress the reaction of blood can not. Leukocytosis will come to a normal level on its own with recovery.
In case of internal organs transplantation, special means( immunosuppressants) must be used to block the organ rejection reaction.
Video about the types of leukocytes in the blood and their functions:
A blood test is important for the doctor's prescription. It will help in the timely diagnosis and treatment.