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Leukocyte count
Last reviewed: 05.07.2025

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The white blood cell count is the percentage ratio of different types of white blood cells in a blood smear. When assessing the white blood cell count, it is sometimes necessary to take into account the absolute content of individual types of white blood cells.
Changes in the leukocyte formula accompany many diseases and are often non-specific. However, the diagnostic value of this study is great, as it gives an idea of the severity of the patient's condition and the effectiveness of the treatment. In hemoblastoses, a study of the leukocyte formula often allows for a clinical diagnosis.
Leukocyte formula is the percentage ratio of different types of leukocytes in a blood smear.
Reference values (norm) are reflected in the table, which shows
Cells |
Content, % |
||||
Adults |
At birth |
1 day |
4 days |
2 weeks |
|
Myelocytes |
- |
0.5 |
0.5 |
- |
- |
Metamyelocytes |
- |
4 |
4 |
2.5 |
1.5 |
Band neutrophils |
1-5 |
27 |
26 |
7 |
3 |
Segmented neutrophils |
40-70 |
34 |
34 |
39 |
25 |
Lymphocytes |
20-45 |
22.5 |
24 |
36.5 |
55 |
Monocytes |
3-8 |
8 |
9.5 |
11 |
11.5 |
Eosinophils |
1-5 |
3 |
2 |
3.5 |
3 |
Basophils |
0-1 |
0.75 |
0.25 |
- |
0.5 |
Plasma cells |
- |
0.25 |
0.25 |
0.5 |
0.5 |
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