Neutrophil Count

What it is

Neutrophils are a type of white blood cell, a crucial part of your immune system. Think of them as the body's first responders, rapidly mobilising to fight off invaders like bacteria and fungi. They are the most common type of white blood cell, making up a significant proportion of your circulating immune cells.

A neutrophil count is a measurement of how many neutrophils are present in a specific volume of your blood. This count is usually part of a broader blood test called a Full Blood Count (FBC), which looks at various components of your blood, including red blood cells, other white blood cells, and platelets. The result is typically given in billions of cells per litre of blood (10^9/l). In the UK, a typical reference range for neutrophils is between 2 and 7.5 x 10^9/l, though this can vary slightly between laboratories.

Why it matters

Your neutrophil count provides valuable insights into your body's ability to fight infection and inflammation. When your body encounters a bacterial or fungal threat, it ramps up the production of neutrophils to combat it. Therefore, an elevated neutrophil count can signal that your immune system is actively engaged in fighting off an infection.

Conversely, a low neutrophil count might suggest that your body's defence system is compromised, potentially making you more vulnerable to infections. This is why monitoring neutrophil levels can be an important part of assessing your overall health and immune status.

What can cause it to be high or low

Several factors can influence your neutrophil count, leading to levels that are higher or lower than the typical reference range.

Higher Neutrophil Count (Neutrophilia):

• Infection: This is the most common reason for a high neutrophil count. Bacterial infections, in particular, trigger a significant increase in neutrophil production. Fungal infections can also lead to this.
• Inflammation: Conditions causing inflammation in the body, such as autoimmune diseases (like rheumatoid arthritis) or tissue damage (from injury or surgery), can also raise neutrophil levels.
• Stress: Significant physical or emotional stress can temporarily increase neutrophil counts.
• Certain Medications: Some medications, including corticosteroids, can cause a rise in neutrophils.
• Leukaemia: In rarer cases, certain types of leukaemia (cancers of the blood) can lead to very high neutrophil counts, although these neutrophils may not function normally.

Lower Neutrophil Count (Neutropenia):

• Viral Infections: Some viral infections can temporarily suppress bone marrow function, leading to a drop in neutrophils.
• Bone Marrow Problems: Conditions affecting the bone marrow, where neutrophils are produced, can cause low counts. This includes aplastic anaemia or certain leukaemias.
• Autoimmune Conditions: In some autoimmune diseases, the body mistakenly attacks and destroys its own neutrophils.
• Certain Medications: Chemotherapy drugs used to treat cancer are a common cause of neutropenia, as they target rapidly dividing cells, including those in the bone marrow. Some other medications can also lower neutrophil counts.
• Severe Infections: While infections usually raise neutrophil counts, overwhelming or severe infections can sometimes deplete them, leading to a paradoxical drop.
• Nutritional Deficiencies: Severe deficiencies in certain vitamins, like B12 or folate, can impact the production of blood cells, including neutrophils.

Lifestyle factors that may help

While your neutrophil count is primarily influenced by your immune system's response to illness and other medical factors, certain lifestyle choices can support overall immune health, which in turn may help maintain healthy blood cell levels. These are areas you might wish to discuss with your GP.

• Balanced Diet: Ensuring you have a diet rich in vitamins and minerals is fundamental for healthy immune function. This includes adequate intake of fruits, vegetables, lean proteins, and whole grains.
• Adequate Sleep: Getting sufficient, good-quality sleep is vital for your immune system to function optimally and for your body to repair itself.
• Stress Management: Chronic stress can impact your immune system. Exploring techniques like mindfulness, gentle exercise, or hobbies can be beneficial.
• Regular, Moderate Exercise: Engaging in regular physical activity can support your immune system. It's generally advised to avoid over-exertion, especially if you have concerns about your immune status.
• Good Hygiene: Practising good hand hygiene is a simple yet effective way to reduce your exposure to infections, thereby lessening the burden on your immune system.

Questions to discuss with your GP

If your neutrophil count has been measured, or if you have concerns about your immune health, here are some questions you might consider discussing with your GP:

• What does my specific neutrophil count mean in the context of my overall health?
• Are there any underlying conditions that might be affecting my neutrophil levels?
• What are the potential causes for my neutrophil count being higher or lower than the reference range?
• Are there any lifestyle adjustments you would recommend to support my immune system?
• Do I need any further tests to investigate my neutrophil count?
• What signs or symptoms should I be aware of that might indicate an infection or a problem with my immune system?