White blood cells are the main component of the body's defense against disease. For example, the white blood cell count at 6 years is 5–12. They protect the body from the invasion of microorganisms and cells with mutant DNA and cleanse the body. Platelets are necessary for the "repair" of blood vessels when they are damaged; they also provide growth factors and healing. It is worthwhile to learn more about the white blood cell count in a child of 6 years old (also older and younger).
To check the number of leukocytes, it is necessary to take a general blood test. The white blood cell norm in adult men and women is 4-9x10 9 . In some laboratories, reference values (norms) of the content of leukocytes are expanded and amount to 3.2-10.6x10 9 . In children, these indicators are higher: at the age of up to one year in the blood there are 6.5-12.5 x 10 9 of these cells, up to three years - 5-12 x 10 9 , up to six - 4.5-10 x 10 9 , up to sixteen - 4.3-9.5 x 10 9 .
White Taurus Characteristics
Although white blood cells and red blood cells come from hematopoietic stem cells in the bone marrow, they are very different from each other in many significant ways.
For example, the first is much smaller than the second: usually their number is from 5000 to 10000 per 1 μl. They are also larger than them and are the only educated elements that are considered complete cells with a nucleus and organelles. Although there is only one type of red blood cell, there are many types of white blood cells. Most of them have a much shorter lifespan than red blood cells, in some it is short, only a few hours or even several minutes in case of acute infection.
One of the most striking characteristics of leukocytes in the urine of a child of 6 years is their movement. While red blood cells spend their days circulating in blood vessels, white blood cells usually leave blood flow to fulfill their protective functions in body tissues. For leukocytes, the vasculature is just a highway in which they travel and soon exit to reach their true destination. When they arrive, they are often given various "names", such as macrophage or microglia, depending on their function.
As soon as they exit the capillaries, some of them will occupy fixed positions in the lymphatic tissue, bone marrow, spleen, thymus, or other organs. Others will move through tissue spaces very similar to amoebae, continuously expanding their plasma membranes, sometimes wandering freely, and sometimes moving in the direction in which they appear by chemical signals.
This attraction of white bodies is due to positive chemotaxis (literally - “movement in response to chemicals”) - a phenomenon in which wounded or infected cells and nearby leukocytes emit the equivalent of a chemical “911” call, sending more “rescuers” to the desired location .
In clinical medicine, differential calculations of the types and percentages of white bodies present are often key indicators in diagnosing and choosing treatment. Therefore, if the urine contains 6 - 10 leukocytes, then they can be called the norm and not to worry about anything. But is this value a normal indicator for adults? Yes. For example, if women have 6.6 leukocytes in the urine, then this is an indicator of health.
White Taurus Classification
When scientists first began to study the composition of blood, it quickly became apparent that white blood cells can be divided into two groups, depending on whether the original granules are contained in the cytoplasm:
- Granular species are distinguished by abundant granularity in the cytoplasm. These include neutrophils, eosinophils and basophils. In children at 6 months, white blood cells will be normal with a value of 6.6.
- Although granules are not completely absent in agranular leukocytes, they are much smaller and less obvious. This species includes monocytes that mature into macrophages. The latter are phagocytic and lymphocytes, which arise from the line of lymphoid stem cells. The norm of leukocytes at 6 years old is 5–12.
The normal amount in women
The number of white bodies is one of the most significant characteristics in a blood test. In the body of a woman, white blood cells should be from 3.2 * 10 9 / l to 10.2 * 10 9 / l. A change in the degree of immune cells occurs in 2 cases: with diseases of the blood and blood-forming materials and with pathologies of other organs and systems. The phase of the monthly cycle with a hormonal background has a great influence on the number of bodies. In addition, white blood cells during pregnancy are very “jumping”, and it is considered normal if their level reaches 15 * 10 9 / L.
Norms in men
They should have from 4 to 9 * 10 9 / l of leukocytes in their blood. Their degree in the male body varies little in comparison with other groups of patients. The following conditions can affect the number of white blood cells in the blood:
- unusual physiological stress;
- stress;
- change the power menu.
White blood cells 6.6 are normal in this case.
In children
As a rule, if in the bodies of older people the number of white bodies is approximately equal, then in children it varies significantly. Their degree varies even depending on the age of the child:
- in infants up to a month: 8 - 13 * 10 9 / l;
- in children from 2 to 12 months: 6 - 12 * 10 9 / l;
- in a child from a year to 3: 5 - 12 * 10 9 / l;
- in children from 3 to 6: 5 - 10 * 10 9 / l;
- children from 6 to 16: 5 - 9.5 * 10 9 / l.
The increased content of immune cells is explained by the fact that in the infant body a greater number of different actions are performed. All organs and systems of the child are rearranged and adapt to existence outside the mother’s womb. In addition, the development of immunity takes place, which causes an increase in white blood cells in the blood. As they grow older, their degree decreases. If this is done, then the immune system has strengthened.
Granular white blood cells
What does the presence of granular white bodies indicate in the printout of a blood test? We will consider their meaning in order from the most common to the least known. All of them are made in red bone marrow and have a short life: from several hours to several days. They usually have a lobed core and are classified according to what type of spots their granules best discharge.
1) The most common of all white blood cells are neutrophils, as a rule, they make up 50-70 percent of their total number. They have a diameter of 10-12 microns, significantly larger than red blood cells. They are called neutrophils, because their granules are most clearly manifested with chemically neutral spots (neither acids nor bases).
Neutrophils respond quickly to the site of infection and are effective phagocytes with a preference for bacteria. Their granules include lysozyme - an enzyme that can lyse or destroy: walls of bacterial cells; oxidizing agents such as hydrogen peroxide; defensins; proteins that bind; purge the bacterial and fungal plasma membranes so that the contents of the cells flow.
An abnormally high neutrophil count in the analysis indicates infection and / or inflammation, especially caused by bacteria, but is also found in burn patients and others experiencing unusual stress. Burn injury increases the proliferation of neutrophils to fight off the infection, which may result from the destruction of the skin barrier. Low rates can be caused by toxicity of the drug and other disorders, show a person's increased susceptibility to infection.
2) Eosinophils usually make up 2-4 percent of the total white blood cell count. They also have a diameter of 10-12 microns. Their granules are best stained with an acidic stain known as eosin. The core of the eosinophil, as a rule, has two to three lobes and, if properly stained, the granularity will take on a bright red and orange color.
Eosinophil granules include antihistamines that resist the action of histamines and inflammatory chemicals produced by basophils and mast cells. Some eosinophil granules contain molecules that are toxic to parasitic worms that can enter the body through the skin, or when a person consumes raw or undercooked fish and meat.
Eosinophils are also capable of phagocytosis and are especially effective when antibodies bind to the target and form an antigen-antibody complex. High eosinophil counts are typical for patients with allergies, parasitic worm infections, and some autoimmune diseases. Low rates can be caused by toxicity and stress.
3) Basophils are the least common cells, usually constituting no more than one percent of the total number of leukocytes. They are slightly smaller than neutrophils and eosinophils: with a diameter of 8-10 microns. Basophil granules are best stained with basic (alkaline) spots. Basophils contain a curved nucleus, which is almost imperceptible under the cytoplasm.
In general, they block the spread of toxins in the tissues and "force" other types of cells to actively move towards the focus of damage to the body. They are similar to mast cells by this factor. Previously, the latter were considered basophils, but they left the bone marrow in a ripe form, which allowed scientists to separate these 2 species.
Basophil granules secrete histamine, which promotes inflammation, and heparin, which counteracts blood coagulation. High basophils in the analysis are associated with allergies, parasitic infections and hypothyroidism. Low ones indicate pregnancy, stress, and hyperthyroidism.
Agranular white blood cells
What does the presence of this type of cell in a blood test mean? Agranular bodies contain less visible granules in their cytoplasm than granular leukocytes, 6.6 for which is a normal indicator. The core is simple in shape, sometimes indented, but without separate lobes. There are two main types of agranulocytes: lymphocytes and monocytes.
1) The former are the only formed blood element that arises from lymphoid stem cells. Although they initially form in the bone marrow, most of their subsequent development and reproduction occurs in the lymphatic tissues. Lymphocytes are the second most common type of white blood cells, accounting for about 20-30 percent of all blood cells, and they are necessary for the immune response.
There are three main groups of lymphocytes that include natural killer cells: B and T. Natural killer (NK) cells are capable of recognizing cells that do not express their own proteins on their plasma membrane or contain foreign or abnormal markers. These “non-self-propelled” cells include cancer, virus-infected, and others similar to them with atypical surface proteins. Thus, they provide generalized, non-specific immunity. Large lymphocytes are usually NK cells.
B and T bodies play an important role in protecting the body from specific pathogens (pathogens) and are involved in specific immunity. One form of B-cells (plasma) produces antibodies or immunoglobulins that bind to specific foreign or abnormal components of plasma membranes. This is also called the immune system (humoral).
T cells provide cellular level protection by physically attacking foreign or diseased pathogens. The memory cell is a set of B- and T-cells, which are formed after exposure to the "aggressor" and quickly respond to subsequent attacks. Unlike other white blood cells, memory cells live for many years.
Abnormally high lymphocyte counts are characteristic of viral infections, as well as certain types of cancer. Abnormally low ones speak of a prolonged (chronic) illness or immunosuppression, including those caused by HIV infection and drug therapy, which includes steroids.
2) Monocytes come from myeloid stem cells. They usually make up 2-8 percent of the total white blood cell count. These cells are recognized by their large size (12-20 microns) and padding or horseshoe-shaped nuclei.
Macrophages are monocytes that have left the circulation and phagocytose debris, foreign pathogens, worn red blood cells and many other dead, worn out or damaged cells. Macrophages also release antimicrobial defensins and chemotactic chemicals that attract other white blood cells to the site of infection. Some macrophages occupy fixed locations, while others wander through tissue fluid.
The abnormally high number of monocytes in the analysis is associated with viral or fungal infections, tuberculosis, some forms of leukemia, and other chronic diseases. Abnormally low rates are usually caused by bone marrow suppression.
Leukopenia
A condition in which too few white blood cells are formed. If this condition is expressed, the individual cannot prevent the disease. Excessive leukocyte proliferation is known as leukocytosis. Although their number is large, the cells themselves are often dysfunctional, which leads to an increased risk of the disease. But if the child’s blood contains leukocytes 6, 6, then do not worry. After all, this value fits into the norm. The following is a leukocyte count for leukopenia.
Leukemia
Cancer with an abundance of white blood cells. It can include only one specific type of leukocyte from myeloid (myelocytic leukemia) or lymphoid line (lymphocytic leukemia). In chronic leukemia, mature white bodies accumulate and do not die. In acute leukemia, overproduction of young, immature cells occurs. In both cases, the cells do not function properly. The indicators are shown in the photo below.
Lymphoma
A form of cancer in which masses of malignant T and / or B lymphocytes collect in the lymph nodes, spleen, liver, and other tissues. As with leukemia, malignant white blood cells do not function properly, and the patient is vulnerable to infection. Some forms of lymphoma tend to progress slowly and respond well to treatment. Others, as a rule, develop rapidly and require aggressive treatment, without which they are fatal. For example, in children the norm of white blood cells at 6 months is 5.5-12.5, which means these indicators are not a pathology. Whether they are higher or lower, you can sound the alarm.
Platelets
Sometimes platelets can be seen in the transcript of the analysis (as in the table above), but since this name suggests that they are a type of cell, this is inaccurate. Platelets are not, but rather a fragment of the cytoplasm called megakaryocyte, which is surrounded by a plasma membrane. Megakaryocytes come from myeloid stem cells, and are large, usually 50-100 microns in diameter, and contain an enlarged, lobed nucleus.
As a rule, thrombopoietin, a glycoprotein secreted by the kidneys and liver, stimulates the proliferation of megakaryoblasts that mature into megakaryocytes. They remain in the bone marrow tissue and ultimately form an extension of the precursor platelets that extend through the walls of the bone marrow capillaries to release thousands of cytoplasmic fragments into the blood circulation, each of which is limited by a small plasma membrane.
These closed fragments are platelets. Each megakarocyte produces 2000-3000 of them during its life span. After platelet isolation, the remains of megakaryocytes, which are slightly larger than the cell nucleus, are consumed by macrophages.
Diseases and Platelets
Thrombocytosis is a condition in which there are too many of them. This can trigger the formation of unwanted blood clots (thrombosis), a potentially fatal disorder. If there is an insufficient number of platelets called thrombocytopenia, the blood may not thicken properly and excessive bleeding can occur.
We examined the percentage of leukocytes and platelets in a blood test, which can cause them to deviate from the norm.