Hematology and Clinical Microscopy Glossary - College of American ...

Neutrophil, Stained
Usually the neutrophil is easily recognized. The nucleus
often is segmented or lobulated (two to five lobes)
and is connected by a thin filament of chromatin. The
abundant, pale pink orcolorless cytoplasm contains
many fine, lilac neutrophilic granules.
In smears, artifacts, cellular distortion, and cellular
degeneration are common. The nuclear lobes may
appeareccentric and the cytoplasm may contain
toxic granules or bevacuolated. Neutrophils may
show morphologic changes dueto autolysis, including
nuclear pyknosis and fragmentation,making
recognition of the cell type difficult.
Eosinophil, Stained
Eosinophils are recognized by their characteristic
brightorange-red spherical granules. They typically
have a bilobed nucleus separated by a thin filament.
Occasionally, more than two lobes may be seen.
The granules are larger.
Clinical Microscopy Miscellaneous Cell
Introduction to Stained Stool and Nasal Smears
for Eosinophils
It is sometimes useful to characterize the cellular elements in a bodily product. In stool, the presence of
neutrophils is suggestive of certain enteric pathogens. Shigella dysentery will have neutrophils present in
approximately 70% of cases; Salmonella and Campylobacter will demonstrate neutrophils in 30% to 50%
of cases; and noninvasive organisms, such as Rotavirus and toxigenic Escherichia coli, will show neutrophils in
only 5% of cases. Smears are prepared by selecting flecks of mucus from fecal material with a cotton swab that
is then rolled across a glass slide. The smear is allowed to air dry and is then stained with a Wright-Giemsa stain.
Nasal smears for eosinophils are useful in distinguishing the nature of a nasal discharge. In nasal smears, the
identification of eosinophils is a correlate of allergic rhinitis. In discharges due to allergy, the predominant cell is
the eosinophil. In contrast, nasal discharge due to nonallergic causes will show either a predominance of
neutrophils or acellular mucus. Infectious processes show predominantly neutrophils. The slide is prepared by
having the patient blow his/her nose in a nonabsorbent material (eg, waxed paper, plastic wrap). A swab is
then used to transfer the mucus to a glass slide. A thin smear (one through which newspaper can be read) is
essential. Cytologic detail is lost if the smear is too thick. The smear is then allowed to air dry and is stained. In
nasal smears, usual Wright-Giemsa blood stains may yield bluish rather than red granules in eosinophils. Many use
a Hansel stain instead, as eosinophils stain bright red whereas neutrophils and mucus debris have a blue color.
Since the characteristics of eosinophils and neutrophils are the most important features in stool and nasal
smears, these are described below.
References
Bachert C. Persistent rhinitis-allergic or nonallergic?
Allergy.2004;59 Suppl 76:11–15; discussion 15.
Echeverria P, Sethabuti O, Pitarangsi C. Microbiology
and diagnosis of infections with Shigella and
enteroinvasive E. coli. Rev Infect Dis. 1991;13 Suppl
4:S220–225.
Hansel FK. Cytologic diagnosis in respiratory allergy
and infection. Ann Allergy. 1996;24(10);564–569.
Huicho L, Sanchez D, Contreras M, et al. Occult blood
and fecal leukocytes as screening tests in childhood
infectious diarrhea. Pediat Infect Dis J.1993;12(6):474–
477.
Mullarkey MF, Hill JS, Webb DR. Allergic and non-
allergic rhinitis: their characterization with
attention to the meaning of nasal eosinophilia.
J Allergy Clin Immunol.1980;65(2):122–126.
Scadding GK. Non-allergic rhinitis: diagnosis and
management.Curr Opin Allergy Clin Immunol.
2001;1(1):15–20.
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