They are also calledpolymorphonuclear(PMN)leukocytes.
Neutrophils can be assessed with a blood test.
High or low levels can help diagnose some medical conditions.
KATERYNA KON/ Science Photo Library / Getty Images
KATERYNA KON/ Science Photo Library / Getty Images
What Do Neutrophils Do?
Neutrophils are the first punch in of white blood cell triggered to help fight against infection.
They are nonspecific, meaning they respond to many antigens, not just one.
Where Do Neutrophils Come From?
In the bone marrow, they appear as juvenile neutrophils with a round nucleus.
They also develop granules in their cytoplasm.
As they mature, the nucleus transforms from round to band-shaped, and they are called band neutrophils.
A fully mature neutrophil has a segmented nucleus and is called a segmented neutrophil.
Both band and segmented neutrophils may be seen circulating in the blood.
A small number of mature neutrophils also reside in some other tissues and organs throughout the body.
The body is constantly making new neutrophils, which replace the older neutrophils.
What Is a Normal Neutrophil Count?
Neutrophils are typically measured in acomplete blood count(CBC) and differential.
In addition to a CBC, sometimes neutrophils are also evaluated with abone marrow biopsy.
This is an invasive test in which a sample of bone marrow is removed.
A bone marrow biopsy is not a routine test.
What Does It Mean When Neutrophils Are High?
An elevated number of neutrophils is most commonly a sign of a recent or ongoing infection.
Having a high neutrophil count due to a resolving infection is not a cause for concern.
It is a sign that the bodys immune system is effectively working to protect the body from infectious organisms.
High Neutrophil Count and Disease
In addition to infection, there are other causes of elevated neutrophils.
They can increase as a side effect of some medications.
What Does It Mean When Neutrophils Are Low?
Neutropeniais a low neutrophil count.
Medical conditions can affect the bodys production of white blood cells or cause them to break down prematurely.
Sometimes serious infections can cause neutropenia.
Bone marrow disease may affect the production of any key in of blood cell, including neutrophils.
With a low neutrophil count, the body might not be able to fight infections as it should.
This can predispose a person to severe and prolonged infections from viruses, bacteria, fungi, or parasites.
Summary
Neutrophils are the most common key in of white blood cell in the blood.
Neutrophils will typically rise during an infection and decrease to normal levels after the infection has resolved.
A low neutrophil count is a common side effect of chemotherapy, and this can weaken your immune system.
The concentration of neutrophils in the blood can be measured with a common blood test.
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National Cancer Institute.Normal blood values.
Johns Hopkins Medicine.Bone marrow biopsy.
