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Leukocytes: norm
Last reviewed: 05.07.2025
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Leukocytes norm is an indicator of the health of all human systems and organs. Their main task is to provide a protective function, resist infections, viruses and other harmful agents.
Leukocytes have two main types: granulocytes and agranulocytes. Granulocytes are granular cells, their subgroup includes eosinophils, neutrophils, basophils. The second group - non-granular - includes monocytes and lymphocytes.
The normal level of the body's defense is the leukocyte index (4–9) x 10 9 /l of blood. The quantitative parameter of leukocytes is directly related to the activity of the bone marrow, where leukocytes are formed. Partially, these white blood cells are formed in the spleen, lymph nodes. The norm of leukocytes can fluctuate depending on the speed of their production, the speed of mobilization from the bone marrow, the speed of penetration into tissues and other factors. Phagocytic activity is invaluable, they, dividing into subspecies, perform a lot of useful actions: they recognize foreign elements, capture them, hydrolyze, and utilize, remove them from the body.
[ What is the normal leukocyte count?
The leukocyte norm is a specific leukocyte formula, where the indicators of individual subtypes are calculated as a percentage.
The following parameters are considered normal:
Leukogram of granulocytes (neutrophils):
- Myelocytes (newborn leukocytes) – 0;
- Metamyelocytes (young) – 0-1;
- Band cells – 1-5;
- Segmented – 45-70;
- Eosinophils – 1-5;
- Basophils – 0-1. 2.
Leukogram of agranulocytes:
- Lymphocytes – 20-40;
- Monocytes – 2-10.
Leukocytosis is a deviation from the norm of over tens of thousands, which may indicate acute inflammatory processes, infectious pathologies of organs and systems. Leukocytosis is also designated by a specific term - a shift in the leukocyte formula to the left. If the leukocyte norm is exceeded by hundreds of thousands, this is a threatening sign indicating leukemia. Changes in neutrophilic indices indicate degranulation (cell damage, pathological changes in its structure), vacuolization (cellular dystrophy with the formation of cavities containing fluid).
Leukopenia is a change in indicators towards a decrease in quantity. A decrease below the threshold of 4000 is mortally dangerous for the body. Agranulocytosis is an almost complete vulnerability of systems and organs to infections, viruses and intoxications.
The leukocyte norm is also an age-related indicator of health:
Children:
- First day of life – 8.5 – 24.5x109/l;
- First month of life – 6.5 – 13.5x109/l;
- Six months of age – 5.5 – 12.5x109/l;
- One year – 6.0 – 12.0x109/l;
- Up to six years – 5.0 – 12.0x109/l;
- Up to twelve years – 4.5 – 10.0x109/l;
- Up to fifteen years – 4.3 – 9.5x109/l.
Adults regardless of gender:
- 4.0 – 9.0x109/l;
The normal rate for pregnant women in the first trimester is slightly elevated, while an increase in leukocytes in the third trimester indicates a hidden pathology.
Leukocytes norm is information that shows the state of the body at rest, without the influence of provoking factors, both physiological (food intake, physical activity) and psycho-emotional. Therefore, the analysis to determine leukocytes is carried out on an empty stomach, excluding all possible loads.