Neutrophils too high or too low: what your value means

If your neutrophils are too high, there are more of these white blood cells in your blood than expected. The range usually runs from 1.5 to 7.0 billion per litre. A bacterial infection is the best known cause, but stress, smoking and prednisone do the same thing.

Before you read on, one thing that removes half the confusion.

Your report carries two numbers for neutrophils: a percentage and an absolute count. Only the absolute count matters. The percentage can look high while nothing is wrong, and I will come back to that.

What do neutrophils do?

Neutrophils are the most numerous white blood cells, making up roughly 40 to 70 percent of the total. They are the first line of defence against bacterial infection. Within hours they reach the inflammation and clear bacteria. They live briefly, often less than a day.

They belong to the granulocytes. To understand how that group fits together, our article on granulocytes explains their functions.

This page is about something else: what to do when the number on your report is off.

Percentage or absolute count, which do you read?

Always read the absolute count, in billions per litre. The percentage only tells you what share of your white cells are neutrophils, so it rises automatically when another cell type falls. You can have a neutrophil percentage of 80 while the absolute count is perfectly normal.

This is the most common misreading of a differential, and I see it weekly.

Picture someone with 3.0 neutrophils and 4.0 white blood cells in total. That is 75 percent, which looks high.

Yet 3.0 sits comfortably inside the range.

Nothing is raised. Only the ratio shifted, because the lymphocytes were low.

What is a normal neutrophil count?

In adults the reference range usually runs from 1.5 to 7.0 x 10^9 per litre, with exact limits differing by laboratory. Look up your own absolute number below.

Note the 1.0 to 1.5 row. It is there for a reason, and the reason appears further down this page.

What do high neutrophils mean?

A raised neutrophil count is called neutrophilia and usually means your body is responding to something. Bacterial infection is the best known cause. But physical stress, hard exercise, smoking and pregnancy raise the count too. Prednisone and other corticosteroids do the same.

That last one surprises people. Corticosteroids release neutrophils that were resting against the vessel wall, so they join the circulation. No new cells are made; they simply become visible to the measurement.

A hard training session or a stressful morning does something similar on a smaller scale.

If the value stays raised for a long time without infection or medication, further work follows. Persistent neutrophilia warrants investigation of rarer bone marrow causes, including testing for the BCR-ABL gene (PMID 38760992).

That is a next step for the doctor, not something to look up yourself after a one-off reading of 8.2 during a cold.

What do low neutrophils mean?

A reduced neutrophil count is called neutropenia. Below 1.5 counts as mildly low and below 0.5 as severe, where infection risk clearly rises. Viral infections, some medicines and a vitamin B12 deficiency are common causes.

A temporary dip after flu is normal and recovers on its own.

Chemotherapy is the best known medical cause, and people receiving it are always given specific explanation and instructions.

Thuisarts and the NHG guidelines describe when a GP investigates a low count further and when a repeat is enough.

When a low count is simply normal

In people of African, Caribbean and Middle Eastern ancestry, a lower neutrophil count is common. It is entirely benign. It is called benign ethnic neutropenia and rests on the Duffy-null phenotype, a common genetic variant. These people are not more susceptible to infection.

This matters because the reference values on your form are usually based on a Northern European population. A value of 1.3 can then be read as abnormal when it is not.

The genetic explanation is now well described (PMID 30117263, PMID 30592023).

I mention it explicitly because it almost never appears in Dutch consumer information. For part of the population it is the most likely explanation.

If this describes you, mention your ancestry when discussing your result. It may save a follow-up pathway that finds nothing.

Which values do you read beside your neutrophils?

Always read your neutrophils alongside your total white cell count and the other cell types in the differential. A raised total driven by neutrophils points more towards a bacterial cause, while a shift towards lymphocytes fits a viral infection more often.

• Leukocytes for the overall white cell picture.
• Lymphocytes for the viral side.
• Monocytes for the clean-up that follows.
• Eosinophils for allergy and parasites.

The red side of your report is separate, but measured in the same complete blood count, together with your haematocrit.

The differential is part of our extended health checkup, and you can add it separately through your own custom blood test.

My advice: do not have blood drawn straight after heavy training or a sleepless night. Have an abnormal value repeated after a few weeks.

This information is general and does not replace medical advice. Blood results from Vitalcheck are reviewed by a BIG-registered doctor. Always discuss an abnormal result with your own GP.

References

• BCR-ABL testing in the evaluation of neutrophilia. Am J Hematol, 2024. PMID 38760992
• Ethnic benign neutropenia: A phenomenon finds an explanation. Pediatr Blood Cancer, 2018. PMID 30117263
• The Duffy antigen receptor for chemokines, ACKR1, Jeanne DARC of benign neutropenia. Br J Haematol, 2019. PMID 30592023
• NHG guidelines and Thuisarts, on abnormal white cell counts in primary care