7
Microbiology, Inflammation, and Viral Infections
Fig. 7.11 "Clue cells"
phase contrast. Vaginopancervical smear
(unstained x MP).
Fig. 7.12 Gardnerella vaginalis (BV) infection.
Vaginopancervical smear
(Papanicolaou x LP).
of three bacteria in the
Clostridiales
order. These are named as
bacterial vaginosis-associated bacterium (BVAB1, BVAB2, and
BVAB3). BVAB are considered highly specific for BV infection.22
Patients with a high pH of the vagina have a vaginal discharge
with a distinct fishy odor. When the pH is further raised by
potassium hydroxide (KOH), this odor is manifest in the "whiff
test."23 Such preparations of vaginal reactions and KOH, when
examined microscopically, have the diagnostic "clue cells" (Fig.
7.11). These refer to normal polygonal squamous cells having
thin, transparent cytoplasm covered by tiny coccobacillary forms
of
G. vaginalis.
Edges of the "infected" cells reveal the BV changes.
The cell borders may be indistinct and on a different plane of
focus. Similar clue cells are observed in the fixed and stained
Papanicolaou preparations (Fig. 7.12). A variable amount of
acute inflammation may be present in the background. Mere
complete or partial covering of the squamous epithelial cells by
the organisms (Fig. 7.13) or their sticking to the cellular mar-
gins (Fig. 7.14) per se should not be considered diagnostic for
G.
vaginalis
. To be diagnostic, clue cells should have bacterial
organisms not only covering the surfaces of the affected cells
but also spreading beyond the margins of the squamous cells.
In LBGS preparations, organisms appear in a clean background
(Fig. 7.15). Detection of BV is reported to be considerably less in
Fig. 7.13 Partial obliteration
of the squamous cell by the coccobacillary
organisms. Vaginopancervical smear (Papanicolaou x MP).
Fig. 7.14 Organisms sticking to squamous cell.
Vaginopancervical
smear (Papanicolaou x MP).
LBGS-based preparations than in conventional slides.4 This may
not be an entirely true observation. A high degree of diagnostic
accuracy exists in cytologic detection of clue cells and culture
confirmation for
G. vaginalis.
Schnadig and co-workers24 cul-
tured
G. vaginalis
in nearly 90% of the cases that contained clue
cells. This infection is believed to be sexually transmissible, and
an accurate diagnosis is necessary.
Micrococcus Vaginitis (Toxic Shock)
This entity is now rarely observed in current practice. This group
of microbes includes a large number of Gram-positive coccoid
organisms commonly observed in female genital tract smears,
and Gram-negative diplococci.
Staphylococcus aureus
may be
recovered from the vagina in about 5% of normal women. These
organisms frequently cause vaginitis and vaginal discharge and
may produce toxic shock syndrome. This association was docu-
mented by Shands and co-workers in 1980.25 These organisms
characteristically occur singly and can be seen within the poly-
morphonuclear leukocytes or other infected epithelial cells. In
vaginal smears, occasionally fragments of tampon fibers may be
observed (Fig. 7.16). However, the finding of coccoid organisms
or tampon fibers in the vaginal smear does not have any correla-
tion with the clinical occurrence of toxic shock syndrome.
97
previous page 99 ComprehensiveCytopathology 1104p 2008 read online next page 101 ComprehensiveCytopathology 1104p 2008 read online Home Toggle text on/off