Neutrophils (Neuts, Polys, Neutrophil percentage, Segmented neutrophils (segs), Polymorphonuclear leukocytes (PMNs), Granulocytes (neutrophils are the largest part))

How to read your result

Reading this value takes two steps: first place the percentage against your lab's reference range (typically near 40–70% for adults), then check the total WBC count on the same report. Low percentages usually mean either reduced neutrophil production or survival — from viral infections, medications, autoimmune conditions, vitamin deficiencies, or marrow problems — or a relative effect where lymphocytes rose and shrank the neutrophil share. High percentages usually mean the body has mobilized its defenses: bacterial infection, inflammation, tissue injury, or corticosteroids.

Distance from the range matters. A few points outside the cutoffs in someone who feels well is common and often transient; values below about 20% or above about 88% are strong signals worth prompt attention, especially with fever or feeling ill. And formal thresholds — like the ANC below 500 cells/µL that defines severe neutropenia — are set on the absolute count, not the percentage, so always ask for your ANC when this number is flagged.

What can shift this value

• Corticosteroids (prednisone, dexamethasone) raise the neutrophil percentage, often substantially
• Chemotherapy, antithyroid drugs, clozapine, and some antibiotics can lower it
• Acute bacterial infections push it up; many viral infections push it down by raising lymphocytes
• Smoking raises neutrophil counts chronically
• Strenuous exercise or acute stress shortly before the blood draw temporarily raises it
• Pregnancy, especially the later months, shifts the differential toward neutrophils
• Some healthy people of African or Middle Eastern ancestry run lifelong lower neutrophil counts (benign ethnic neutropenia) with no ill effects
• Time of day plays a small role — counts run modestly higher in the afternoon
• Recent surgery, injury, or burns raise it for days
• Lab-to-lab differences in analyzers and cutoffs mean the same blood can be flagged at one lab and normal at another

When it's tested

Neutrophils are reported on any complete blood count (CBC) with differential — a standard part of annual physicals, emergency-room workups for fever or infection, pre-surgical testing, and monitoring for medications that can suppress bone marrow, such as chemotherapy, clozapine, or methimazole. A basic CBC without the differential reports only the total white count, so if your report has no neutrophil line, the differential simply wasn't ordered. Panels like the CMP or lipid panel do not include it.

A percentage is the same in every country, so no SI conversion applies; the related absolute neutrophil count, however, may appear as cells/µL (or cells/mm³) on US reports and as ×10⁹/L elsewhere — 2,000 cells/µL equals 2.0 ×10⁹/L.