Table of ContentsView AllTable of ContentsFunctionLifespanCountsHigh NeutrophilsLow Neutrophils
Table of ContentsView All
View All
Table of Contents
Function
Lifespan
Counts
High Neutrophils
Low Neutrophils
Neutrophilsare the most common type ofwhite blood cell.Like all white blood cells, they work to fight off infectious organisms in your body, such as viruses and bacteria. They are also calledpolymorphonuclear(PMN)leukocytes.
Neutrophils can be assessed with a blood test. High or low levels can help diagnose some medical conditions.
This article will discuss what neutrophils do, where they come from, and what high or low neutrophil counts mean.
KATERYNA KON/ Science Photo Library / Getty Images
What Do Neutrophils Do?
Neutrophils are the first type of white blood cell triggered to help fight against infection. Once they arrive at the location of a pathogen (infectious organism) in the body, neutrophils have several functions that help the body eliminate the pathogen.
Actions include:
The broken-down infectious material is removed from the body, and the neutrophils are also broken down.
Neutrophils and the Innate Immune SystemNeutrophils are part of theinnate immune system, which is ready to respond to any perceived invader (antigens). They are nonspecific, meaning they respond to many antigens, not just one. Neutrophils do not have a memory, and they don’t make you immune to specific infections the way lymphocytes do.
Neutrophils and the Innate Immune System
Neutrophils are part of theinnate immune system, which is ready to respond to any perceived invader (antigens). They are nonspecific, meaning they respond to many antigens, not just one. Neutrophils do not have a memory, and they don’t make you immune to specific infections the way lymphocytes do.
Where Do Neutrophils Come From?
Neutrophils and all blood cells develop in thebone marrow.Immature neutrophilsmature in the bone marrow for about 14 days and then circulate in the blood. 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.
Neutrophils have a life span in the bloodstream of approximately one day.They migrate into tissues where needed and still have a short remaining lifespan. 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. A CBC is a blood test often done for routine screening or to examine the cause of common symptoms, such as fever, fatigue, swelling, vomiting, difficulty breathing, and more.
There are standard values for the typical number of neutrophils in a blood sample, the percent of white blood cells in a sample that is neutrophils, and how many band or juvenile neutrophils are seen.
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. The sample is sent to a lab to examine the number of neutrophils being formed in the bone marrow and any abnormalities in them.
A bone marrow biopsy is not a routine test. It is usually done to evaluate potential blood cancer or other conditions affecting blood cell production or the bone marrow.
What High and Low Neutrophils Mean on a Blood 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. Typically, in these instances, neutrophils will be elevated for a short period of time as the body fights an infection, and then the neutrophils will eventually decrease to a normal level.
Having a high neutrophil count due to a resolving infection is not a cause for concern. It is a sign that the body’s 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. Certain medical conditions, such as cancer, allergic reactions,autoimmune disorders, trauma, and heart attack, can cause an increase in the number of neutrophils.
In some of these situations, such as during aheart attackor after an injury, the neutrophils work to help reduce damage and to facilitate healing.
Autoimmune conditions may cause neutrophils or other white blood cells to be elevated as the body attacks its own tissue. This may contribute to the symptoms of autoimmune conditions, such as swelling, fever, and pain.But changes in the neutrophil count with autoimmune diseases are usually not significant enough or consistent enough to be used in diagnosis or disease monitoring.
What Does It Mean When Neutrophils Are Low?
Neutropeniais a low neutrophil count. Medical conditions can affect the body’s 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 type of blood cell, including neutrophils.
Chemotherapeutic medications, which are used to treat cancer, can inhibit blood cell production in the bone marrow and sometimes cause premature destruction of neutrophils and other blood cells, leading to neutropenia.
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.
Febrile (high fever) neutropeniais a condition that occurs with some infections, and it can be a sign of a severe bacterial infection that requires medical management.
Conditions that may cause neutropenia include:
Infections, cancer, and autoimmune diseases may increase or decrease neutrophils at different stages of the disease.
Cyclic Neutropenia Symptoms, Diagnosis, and Treatment
Summary
Neutrophils are the most common type of white blood cell in the blood. They tend to be the first to arrive at a location where the body is fighting a pathogen, such as a virus, bacteria, fungus, or parasite, and they have many different, coordinated ways of protecting the body from infections.
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. In certain situations, a bone marrow biopsy may be necessary to determine whether there is an abnormality with neutrophils as they are developing.
Changes in your neutrophil count can be associated with a fever, swelling, fatigue, and susceptibility to infections.
12 SourcesVerywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Hidalgo A, Chilvers ER, Summers C, Koenderman L.The neutrophil life cycle.Trends Immunol. 2019;40(7):584-597. doi:10.1016/j.it.2019.04.013Rosales C.Neutrophil: A cell with many roles in inflammation or several cell types?Front Physiol. 2018;9:113. doi:10.3389/fphys.2018.00113Masucci MT, Minopoli M, Del Vecchio S, Carriero MV.The emerging role of neutrophil extracellular traps (NETs) in tumor progression and metastasis.Front Immunol. 2020;11:1749. doi:10.3389/fimmu.2020.01749Brostjan C, Oehler R.The role of neutrophil death in chronic inflammation and cancer.Cell Death Discov. 2020;6:26. doi:10.1038/s41420-020-0255-6National Cancer Institute.Normal blood values.Johns Hopkins Medicine.Bone marrow biopsy.Honda T, Uehara T, Matsumoto G, Arai S, Sugano M.Neutrophil left shift and white blood cell count as markers of bacterial infection.Clin Chim Acta. 2016;457:46-53. doi:10.1016/j.cca.2016.03.017Zon RL, Berliner N.How I treat: Inpatient consultations for quantitative neutrophil abnormalities in adults.Blood.2022:blood.2021014818. doi:10.1182/blood.2021014818Grune J, Lewis AJM, Yamazoe M, et ak.Neutrophils incite and macrophages avert electrical storm after myocardial infarction.Nat Cardiovasc Res.2022;1(7):649-664. doi:10.1038/s44161-022-00094-wCenters for Disease Control and Prevention.Neutropenia and the risk for infection.Morin EM, Corriveau-Bourque C, Foulds JL.Management and outcome of febrile neutropenia in admitted presumed immunocompetent patients with suspected viral illness.Paediatr Child Health. 2022;27(7):408-413. doi:10.1093/pch/pxac053Mithoowani S, Cameron L, Crowther MA.Neutropenia.CMAJ.2022;194(49):E1689. doi:10.1503/cmaj.220499
12 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.Hidalgo A, Chilvers ER, Summers C, Koenderman L.The neutrophil life cycle.Trends Immunol. 2019;40(7):584-597. doi:10.1016/j.it.2019.04.013Rosales C.Neutrophil: A cell with many roles in inflammation or several cell types?Front Physiol. 2018;9:113. doi:10.3389/fphys.2018.00113Masucci MT, Minopoli M, Del Vecchio S, Carriero MV.The emerging role of neutrophil extracellular traps (NETs) in tumor progression and metastasis.Front Immunol. 2020;11:1749. doi:10.3389/fimmu.2020.01749Brostjan C, Oehler R.The role of neutrophil death in chronic inflammation and cancer.Cell Death Discov. 2020;6:26. doi:10.1038/s41420-020-0255-6National Cancer Institute.Normal blood values.Johns Hopkins Medicine.Bone marrow biopsy.Honda T, Uehara T, Matsumoto G, Arai S, Sugano M.Neutrophil left shift and white blood cell count as markers of bacterial infection.Clin Chim Acta. 2016;457:46-53. doi:10.1016/j.cca.2016.03.017Zon RL, Berliner N.How I treat: Inpatient consultations for quantitative neutrophil abnormalities in adults.Blood.2022:blood.2021014818. doi:10.1182/blood.2021014818Grune J, Lewis AJM, Yamazoe M, et ak.Neutrophils incite and macrophages avert electrical storm after myocardial infarction.Nat Cardiovasc Res.2022;1(7):649-664. doi:10.1038/s44161-022-00094-wCenters for Disease Control and Prevention.Neutropenia and the risk for infection.Morin EM, Corriveau-Bourque C, Foulds JL.Management and outcome of febrile neutropenia in admitted presumed immunocompetent patients with suspected viral illness.Paediatr Child Health. 2022;27(7):408-413. doi:10.1093/pch/pxac053Mithoowani S, Cameron L, Crowther MA.Neutropenia.CMAJ.2022;194(49):E1689. doi:10.1503/cmaj.220499
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read oureditorial processto learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
Hidalgo A, Chilvers ER, Summers C, Koenderman L.The neutrophil life cycle.Trends Immunol. 2019;40(7):584-597. doi:10.1016/j.it.2019.04.013Rosales C.Neutrophil: A cell with many roles in inflammation or several cell types?Front Physiol. 2018;9:113. doi:10.3389/fphys.2018.00113Masucci MT, Minopoli M, Del Vecchio S, Carriero MV.The emerging role of neutrophil extracellular traps (NETs) in tumor progression and metastasis.Front Immunol. 2020;11:1749. doi:10.3389/fimmu.2020.01749Brostjan C, Oehler R.The role of neutrophil death in chronic inflammation and cancer.Cell Death Discov. 2020;6:26. doi:10.1038/s41420-020-0255-6National Cancer Institute.Normal blood values.Johns Hopkins Medicine.Bone marrow biopsy.Honda T, Uehara T, Matsumoto G, Arai S, Sugano M.Neutrophil left shift and white blood cell count as markers of bacterial infection.Clin Chim Acta. 2016;457:46-53. doi:10.1016/j.cca.2016.03.017Zon RL, Berliner N.How I treat: Inpatient consultations for quantitative neutrophil abnormalities in adults.Blood.2022:blood.2021014818. doi:10.1182/blood.2021014818Grune J, Lewis AJM, Yamazoe M, et ak.Neutrophils incite and macrophages avert electrical storm after myocardial infarction.Nat Cardiovasc Res.2022;1(7):649-664. doi:10.1038/s44161-022-00094-wCenters for Disease Control and Prevention.Neutropenia and the risk for infection.Morin EM, Corriveau-Bourque C, Foulds JL.Management and outcome of febrile neutropenia in admitted presumed immunocompetent patients with suspected viral illness.Paediatr Child Health. 2022;27(7):408-413. doi:10.1093/pch/pxac053Mithoowani S, Cameron L, Crowther MA.Neutropenia.CMAJ.2022;194(49):E1689. doi:10.1503/cmaj.220499
Hidalgo A, Chilvers ER, Summers C, Koenderman L.The neutrophil life cycle.Trends Immunol. 2019;40(7):584-597. doi:10.1016/j.it.2019.04.013
Rosales C.Neutrophil: A cell with many roles in inflammation or several cell types?Front Physiol. 2018;9:113. doi:10.3389/fphys.2018.00113
Masucci MT, Minopoli M, Del Vecchio S, Carriero MV.The emerging role of neutrophil extracellular traps (NETs) in tumor progression and metastasis.Front Immunol. 2020;11:1749. doi:10.3389/fimmu.2020.01749
Brostjan C, Oehler R.The role of neutrophil death in chronic inflammation and cancer.Cell Death Discov. 2020;6:26. doi:10.1038/s41420-020-0255-6
National Cancer Institute.Normal blood values.
Johns Hopkins Medicine.Bone marrow biopsy.
Honda T, Uehara T, Matsumoto G, Arai S, Sugano M.Neutrophil left shift and white blood cell count as markers of bacterial infection.Clin Chim Acta. 2016;457:46-53. doi:10.1016/j.cca.2016.03.017
Zon RL, Berliner N.How I treat: Inpatient consultations for quantitative neutrophil abnormalities in adults.Blood.2022:blood.2021014818. doi:10.1182/blood.2021014818
Grune J, Lewis AJM, Yamazoe M, et ak.Neutrophils incite and macrophages avert electrical storm after myocardial infarction.Nat Cardiovasc Res.2022;1(7):649-664. doi:10.1038/s44161-022-00094-w
Centers for Disease Control and Prevention.Neutropenia and the risk for infection.
Morin EM, Corriveau-Bourque C, Foulds JL.Management and outcome of febrile neutropenia in admitted presumed immunocompetent patients with suspected viral illness.Paediatr Child Health. 2022;27(7):408-413. doi:10.1093/pch/pxac053
Mithoowani S, Cameron L, Crowther MA.Neutropenia.CMAJ.2022;194(49):E1689. doi:10.1503/cmaj.220499
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