The white blood cell is a part of the blood test that consists of evaluating the white blood cells, also called white blood cells, which are the cells responsible for the defense of the organism. This test indicates the number of neutrophils, rods or segmented neutrophils, lymphocytes, monocytes, eosinophils and basophils present in the blood.
The increased values of leukocytes, known as leukocytosis, can happen due to infections or blood disorders like leukemia, for example. The opposite, known as leukopenia, can be caused by medication or chemotherapy. Both leukopenia and leukocytosis must be investigated by the doctor to establish the best treatment according to the cause. Learn more about Leukocytes.
White blood cell normal values
The blood count reference values vary according to the person's age and the laboratory, with normal values being:
| Total leukocytes | Neutrophils | Lymphocytes | |
| 1st day of life | 9, 000 to 30, 000 / mm³ | 6, 000 to 26, 000 / mm³ | 2, 000 to 11, 000 / mm³ |
| Between 6 months and 2 years old | 6, 000 to 17, 500 / mm³ | 1, 500 to 8, 500 / mm³ | 3, 000 to 9, 500 / mm³ |
| Between 2 and 3 years old | 5, 500 to 15, 500 / mm³ | 1, 500 to 8, 500 / mm³ | 2, 000 to 8, 000 / mm³ |
| Between 3 and 6 years old | 5, 000 to 14, 500 / mm³ | 1, 500 to 8, 000 / mm³ | 1, 500 to 7, 000 / mm³ |
| Between 6 and 13 years old | 5, 000 to 13, 000 / mm³ | 1, 800 to 8000 / mm³ | 1, 200 to 6, 000 / mm³ |
| Adults | 4, 500 to 11, 000 / mm³ | 1, 800 to 7, 700 / mm³ | 1, 000 to 4, 800 / mm³ |
Leukopenia occurs when leukocytes are less than 4, 500 / mm³ in adults and leukocytosis occurs when leukocytes are greater than 11, 000 / mm³, their value being higher than the reference value.
If you have recently had a white blood cell count and want to know the possible cause of the increase or decrease in the amount of white blood cells, enter your data below:
What is the white blood cell
The white blood cell is required to assess the body's defense system and thus check for inflammation or infection. This test is part of the complete blood count and is done by collecting blood in the laboratory. Fasting is not necessary to perform the test, only when requested together with other tests, such as glucose and cholesterol levels, for example. Understand what it is for and how the blood count is made.
The body's defense cells are neutrophils, lymphocytes, monocytes, eosinophils and basophils, being responsible for different functions in the body, such as:
- Neutrophils: They are the most abundant blood cells in the defense system, being responsible for fighting infections, and may be indicative of infection by bacteria when the values are increased. Rods or rods are young neutrophils and are normally found in the blood when there are infections in the acute phase. Segmented neutrophils are the most mature neutrophils found in the blood; Lymphocytes: Lymphocytes are responsible for fighting viruses and tumors and producing antibodies. When increased, they may indicate a viral infection, HIV, leukemia or rejection of a transplanted organ, for example; Monocytes: These are the defense cells responsible for phagocyting invading microorganisms, also being called macrophages. They act against viruses and bacteria without distinction; Eosinophils: These are the defense cells activated in case of allergy or in infections by parasites; Basophils: These are the defense cells activated in case of chronic inflammation or prolonged allergy and, under normal conditions, only up to 1% are found.
From the result of the white blood cell count and other laboratory tests, the doctor can correlate with the person's clinical history and establish the diagnosis and treatment, if necessary.
