Leukocytes, or white blood cells, are a group of cells in the blood that are in charge of immune responses and the defense of the body against foreign bodies or infectious agents. They originate in the root of the bone marrow and lymphatic tissue, being produced mainly by The hematopoietic stem cell.
Leukocytes are present throughout the body, though mainly in the blood circulatory system. They safeguard the body from the attack of viruses, fungi, bacteria, damaged or cancerous cells, foreign elements and more.
A blood count can be counted by a small volume of blood. This count serves as an indicator of any diseases that may be present. A normal white cel count is anywhere between 4 and 11x11x109/L. This is normally expressed as 4000-11000 white blood cell per microliter.
When this figure increases on the upper limit in a patient, it is said that the patient has a leucocytosis. When the patient had a quantity of leukocytes lower than the limit it is called a leucopenia. In a healthy adult, white blood cells make up about 1% of the total blood volume.
Leukocytes are called white blood cells because, unlike red blood cells, they contain no pigment.
They are made of of a nucleus, mitochondria, and other organelles. Their size varies between 8 and 20 micrometers. Their average life span is anywhere from a few hours to years.
There are various types of leukocytes present in the blood:
Neutrophils: These are responsible for defending the body against attacks of bacterial or fungal origin. They are first to attack when there is the presence of foreign bodies, their large-scale death forms the pus. They die after they have destroyed a few pathogens. In the early stage of inflammation, neutrophils can be found as the most involved cells. They are the most common type of leukocytes present in the blood because they represent approximately 65% of the total and circulating white blood cells and their average life is about 5.4 days.
Eosinophils: These are the leukocytes responsible for fighting parasitic infections. When an allergic reaction occurs, eosinophils are the predominant cells.
Basophils: Basophils are the types of white blood cells responsible for allergic responses, since their main characteristic is that they release histamine, which is a substance that causes vasodilation.
Lymphocytes: Lymphocytes represent approximately 25% of the total leukocytes present in the body, these are responsible for recognizing the foreign agents or antigens that invade the body. According to their structure they are divided into B lymphocytes and T lymphocytes. B lymphocytes are capable of generating antibodies, and are responsible for humoral immunity. T lymphocytes, also known as thymocytes or T cells, are a kind of lymphocytes responsible for the immune response at the cellular level where the bacterial cells or cancer cells recognized as foreign agents are completely destroyed, they are called T lymphocytes because they are produced in the thymus. When T lymphocytes are poorly programmed from birth, they are able to recognize certain organs of the body as antigens, thereby causing autoimmune diseases.
Monocytes: Monocytes are large cells of the immune system and account for approximately 5% of total leukocytes. Its function is to destroy oversized oversized residues in an immune response.
The count of leukocytes reflected in a blood test may show some symptoms of infection or disease.
Low leukocyte analysis
If the white blood cell count is low it may be due to:
Insufficiency of bone marrow due to infections, tumor, poor healing, among other factors.
Spleen or liver disease.
Exposure to radiation.
When leukocyte count is low it is called leucopenia, some treatments like chemotherapy destroy white blood cells causing them to decrease, antibiotics or anti-inflammatories are other factors that could cause a decrease in white blood cells.
If the leukopenia is mild the person may not show any symptoms, only when it is severe, the symptoms begin to be noticed. Among the most common symptoms are:
Anemia: characterized by decreased hemoglobin.
Menorrhagia: very prolonged menstrual period.
Metrorrhagia: bleeding from the uterus due to infection.
Neurasthenia: is an affliction