Neutrophils are a type of leukocyte and are therefore responsible for the body's defenses and immunity. The neutrophils that are in the greatest amount circulating in the blood are called segmented neutrophils and are responsible for involving and eliminating the diseased cells, besides acting in the fight against infections.
Neutrophils are produced in your bone marrow and are circulating in the blood in greater quantity in its mature form, which is called the segmented neutrophils. The normal reference value of circulating segmented neutrophils in the blood is 1600 to 8000 segmented neutrophils per mm³ of blood. Therefore, when neutrophils are high this usually indicates that you have some bacterial or fungal infection, for example.
Sometimes a blood test also can indicate the number of rods and segmented neutrophils. The rods are the neutrophils that have just been produced to overcome an infection and the segmented ones are the oldest and their values can indicate how long the body has been fighting the infection.
The amount of neutrophils can be assessed by performing a blood count, in which the entire white blood series can be checked. Leukocytes are evaluated in a specific part of the blood count, the leukogram can indicate:
1. High neutrophils
The increase in the amount of neutrophils, also known as neutrophilia, can happen due to several situations, the main ones being:
- Inflammatory disorders;
- Eclampsia in pregnancy;
- Hepatic necrosis;
- Chronic myeloid leukemia;
- Post-splenectomy polycythemia;
- Hemolytic anemia;
- Myeloproliferative syndromes;
- Electric shock;
Neutrophilia can also occur due to physiological conditions, such as in newborns, during childbirth, after episodes of repeated vomiting, fear, stress, use of medications with adrenaline, anxiety and after practicing exaggerated physical activity.
Therefore, if you have a high neutrophils count, the doctor may order other diagnostic tests to correctly identify the cause and initiate appropriate treatment.
2. Low neutrophils
A decrease in the amount of neutrophils, also called neutropenia, can occur due to:
- Anemia aplastic, megaloblastic or iron deficiency;
- Use of medications;
- Autoimmune diseases such as Systemic Lupus Erythematosus;
Babies under 3 months of age have low neutrophils, so in cases of serious infections, your blood test may indicate low neutrophils rather than high neutrophils. Children with Down syndrome also tend to have low neutrophils without any health problems.
In the case of neutropenia, the physician may recommend a myelogram to investigate the cause of the decreased amount of segmented neutrophils in the blood, and to check for any changes in the production of neutrophil precursor cells in the bone marrow.