Neutrophilia - Causes, Symptoms, Diagnosis, and Treatment

What Is Neutrophilia?

Neutrophilia is a condition of blood in which the body produces neutrophils in an excessive amount. Neutrophils are white blood cells in the bloodstream synthesis that mature in the bone marrow and fight against inflammation, infection, or neoplasm. Neutrophilia can also be caused due to some underlying disease that eventually increases the count of neutrophils. Increased neutrophils of more than 7700 cells/microliter are known as leukocytosis.

What Are Neutrophils?

Neutrophils are white blood cells (leukocytes), also known as polymorphs, and have tiny granules in the cytoplasm.

• Neutrophils come under the classification of granulocytes. They can take both acidic and basic stains depending on the staining properties of the granules.

• These are colorless, irregular in shape with a nucleus, and have a diameter of 10 to 12 m. The count of neutrophils in an average adult is 4,000 to 11,000/cu mm; in infants, it is about 20,000/cu mm, and in children, it is about 10,000 to 15000/cu mm.

• The neutrophils' lifespan is ten days, of which two to three days in the peripheral tissues and fewer than 24 hours in the circulating bloodstream.

• The count of neutrophils is slightly more in males than in females.

• The cytokines regulate the production, proliferation, differentiation, and circulation of neutrophils in the blood, and the transcription and growth factors control it.

• The count of neutrophils is calculated in percentages by deriving the absolute neutrophil count (ANC).

• The absolute neutrophil count is calculated by multiplying the total number of white blood cells by the percentage of polymorphonuclear cells and immature neutrophil cells.

• Neutrophils are the body's first-line defense system; they accumulate at the site of the infection and fight against the microorganisms.

What Is the Pathophysiology of Neutrophilia?

The increased concentration of neutrophils in the blood is due to inflammatory cytokines released from the area of inflammation within the body. The production of neutrophils is done within the bone marrow, which has a storage pool of mature neutrophils and neutrophil precursors or band cell neutrophils. In addition, blood vessels have free-flowing neutrophils called circulating neutrophils. These neutrophils have cell adhesion molecules that either adhere to the endothelial cells or migrate into the tissues. When the neutrophils adhere to the margins of the endothelial cells, they are called marginal neutrophils.

If there is an inflammation within the tissues and this inflammation is releasing inflammatory cytokines, which indicates the bone marrow releases the storage pool of matured neutrophils. Still, if the inflammation is high, the bone marrow releases neutrophil precursors, band cells, myelocytes, and metamyelocytes. During the inflammation, the marginal neutrophils shift into the circulating pool, and they transit at the site of the inflammation to fight against it; this shift is called the left shift.

In chronic inflammatory reactions and a persistent release of cytokines to the bone marrow for the release of neutrophils, the bone marrow undergoes neutrophilic hyperplasia. These are the mechanisms that induce the increased production of neutrophils.

What Are the Causes of Neutrophilia?

Neutrophilia causes can be classified into the followings:

A. Factitious Neutrophilia:

1. Factitious neutrophilia refers to the false elevation of the neutrophil level in the blood. It can happen at the time of sample collection; the anticoagulant in a test tube, either heparin or EDTA, causes clumping of the platelets in the cell counter system.

2. There is one more possibility of getting factitious neutrophilia by the precipitation of the cryoglobulin particles in the blood samples causing elevation of the neutrophils in the blood.

B. Primary Neutrophilia:

1. Primary neutrophilia can be genetically transmitted. It can be because of gene mutations resulting in the deficiency of the leukocyte adhesion factor. The deficiency of the leukocyte adhesion factor leads to deformity in the leukocyte's adhesion molecule, causing leukocytosis.

2. Chronic idiopathic leukocytosis leads to the elevation of neutrophils, though the individual is asymptomatic and has no underlying disorder. The elevation of neutrophils can also be genetically regulated.

3. Myeloproliferative neoplasm is a disorder related to the excessive production of red blood cells, white blood cells, and platelets.

4. Chronic myeloid leukemia is a blood disorder associated with the excessive production of white blood cells.

5. Essential thrombocythemia elevated neutrophils are seen with the excessive production of red blood cells and platelets.

6. Polycythemia vera is a blood disorder with increased production of red blood cells.

7. Juvenile myelomonocytic leukemia is a malignant blood disorder that mainly affects children causing excessive production of white blood cells, and they remain immature.

8. Leukemoid reaction is a non-malignant blood disorder that involves the excessive production of neutrophils of more than 50,000 cells/cu mm.

C. Secondary Neutrophilia:

1. Infection and inflammation in the body can cause secondary neutrophilia; in response to the condition, the bone marrow produces more white blood cells.

2. Viral Infections can also cause neutrophilia.

3. Tumor or malignancies.

4. Neutrophilia can be seen in ongoing medication treatments and therapy.

5. Medications like Glucocorticoids and Lithium can induce the production of neutrophils.

6. Allergic reactions.

7. Secondary neutrophilia can also be seen in cigarette smokers, obesity, hyposplenism, generalized bone marrow stimulation, physical and emotional stress, and intense exercise.

What Are the Symptoms of Neutrophilia?

In the condition of neutrophilia, the following symptoms can be seen:

1. High-grade fever with high elevation of the neutrophils.

2. Fatigue.

3. Recurrent infections.

4. Pain in joints and bone.

5. Dizziness.

6. Some other underlying acute inflammation causes are leukemia, pneumonia, bowel syndrome, rheumatoid arthritis, and many more.

What Are the Investigations for the Diagnosis of Neutrophilia?

For the diagnosis of neutrophilia, some routine blood tests can be advised. A complete blood count (CBC) test can help to calculate absolute neutrophil count (ANC). It may also help diagnose some underlying conditions due to an elevation in the neutrophils.

What Is the Treatment of Neutrophilia?

Neutrophilia is a curable disorder. It will be recovered if some other underlying disease causes it according to the prognosis of the particular illness. Elevation of neutrophils can be related to day-to-day activities like exercise, smoking, or emotional stress.

Conclusion:

Neutrophilia can be defined as the increased concentration of white blood cells in the blood with the increased production and storage of neutrophils in the bone marrow. Elevation of the neutrophils can be because of other disorders and can be cured as the condition is treated. This elevation also helps in the diagnosis of the disease. A healthy lifestyle, stress management, and boosting immunity can facilitate the elevation of neutrophils.