Neutrophil Segment Count (in Whole Blood)

What Neutrophil Segments Tell Us About Your Health

Neutrophils are a critical part of your immune system. They are the most common type of white blood cell and play a major role in responding to infections, especially bacterial ones. When your body detects bacteria or other harmful substances, neutrophils rush to the site to destroy them. This test helps doctors assess how well your immune system is functioning, especially in cases of infection, inflammation, or certain blood disorders.

When Might You Need This Test?

Your doctor may order a neutrophil segment count if you have symptoms like frequent infections, unexplained fevers, rapid breathing, or signs of inflammation. It’s also used to monitor conditions such as leukemia, autoimmune diseases, or after treatments that might affect your immune system, like chemotherapy.

How Is This Test Performed?

A small sample of your blood is drawn from a vein, usually in your arm. The blood is then analyzed in a lab to count the different types of white blood cells, including neutrophils. This process is quick and typically done in a few minutes.

What Do Low or High Neutrophil Levels Mean?

Low neutrophil counts may indicate an immune deficiency, certain infections, or side effects from medications. High neutrophil counts can signal infections, inflammation, or other underlying health issues like autoimmune diseases or certain cancers.