Neutrophils (aka polymorphonuclear cells, PMNs, granulocytes, segmented neutrophils, or segs) fight against infection and represent a subset of the white blood count. Neutropenia by definition is an absolute neutrophil count below 1800/mm3 (some sources use a lower value).
Total
WBCs:
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How are the Segs and Bands reported:
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Total
Segs (segmented neutrophils):
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Total
Bands:
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Background Info
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Equations:
(1) Segs and bands reported as a percentage:
WBC * ((segs / 100) + (bands / 100))
(2) Segs and bands reported in total numbers:
ANC = (segs + bands) x 1000
Neutrophils (aka polymorphonuclear
cells, PMNs, granulocytes, segmented neutrophils, or segs)
fight against infection and represent a subset of the white blood
count. Neutropenia by definition is an ANC below 1800/mm3 (some
sources use a lower value).
Absolute neutrophil count (ANC) of 1000-1800:
Most patients will be given chemotherapy in this range.
Risk of
infection is considered low.
Mild neutropenia -
Absolute neutrophil count (ANC) of
500-1000:
Carries with it a moderate risk of infection.
Absolute neutrophil count (ANC) of less than
500:
Severe neutropenia - high risk of infection.
Remember that a reduced WBC is known as leukopenia.
The WBC consists of the following
(differential):
Lymphocytes: 20-40%
Neutrophils: 50-60%
Basophils: 0.5-2%
Eosinophils: 1-4%
Monocytes: 2-9% (average: 4%).
ANC = Total WBC x (% "Segs" + % "Bands")
Equivalent to: WBC x ((Segs/100) + (Bands/100))
The ANC refers to the total number of neutrophil granulocytes present in the blood.
Normal value:  1500 cells/mm3.
Mild neutropenia: 1000 - <1500/mm3.
Moderate neutropenia:
500 - <1000/mm3.
Severe neutropenia: < 500/mm3.
Reference:
Ayalew Tefferi, MD, ed. Primary Hematology. Totowa, NJ: Humana Press,
2001.
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