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Genitourinary and Reproductive Function
and postcesarean endometritis, have been shown to be
associated with asymptomatic bacterial vaginosis. It has
also been associated with increased risk of acquisition of
HIV and HSV infection.
The diagnosis of bacterial vaginosis is made when
at least three of the following signs or symptoms are
present: abnormal gray discharge, vaginal pH above 4.5
(usually 5.0 to 6.0), positive fishy odor of vaginal dis-
charge on addition of 10% potassium hydroxide, and
appearance of characteristic “clue cells” on wet-mount
microscopic studies.
4
Because
G. vaginalis
can be a part
of the normal vaginal flora, cultures should not be done
routinely.
Bacterial vaginosis may be treated with oral or topi-
cal metronidazole or clindamycin and oral tinidazole.
Symptomatic pregnant women can also be treated with
metronidazole or clindamycin.
2,4
Some studies have
shown that screening for and treating bacterial vagi-
nosis may reduce the incidence of adverse pregnancy
outcomes. However, studies do not confirm a benefit
from universal testing of low- and medium-risk preg-
nant women.
Vaginal-Urogenital-Systemic
Infections
Some STIs infect male and female genital and extra-
genital structures. Among the infections of this type are
chlamydial infections, gonorrhea, and syphilis. Many
of these infections also pose a risk to infants born to
infected mothers. Some infections, such as syphilis, may
be spread to the unborn infant while in utero, whereas
others, such as chlamydial and gonorrheal infections,
can be spread to the infant during the birth process.
Chlamydial Infections
Chlamydial infection is the most frequently reported
bacterial STI in the United States, with an incidence esti-
mated to bemore than twice that of gonorrhea. According
the Centers for Disease Control and Prevention (CDC),
an estimated 2.86 million infections occur annually.
25
A
large number of cases go unreported because most people
with chlamydia are asymptomatic and do not seek test-
ing. If untreated, chlamydial infections can lead to seri-
ous complications including pelvic inflammatory disease,
infertility, ectopic pregnancy, and chronic pelvic pain.
25
Etiology and Pathogenesis
Chlamydia trachomatis
is an obligate intracellular bac-
terial pathogen that is closely related to gram-negative
bacteria.
9,10
It resembles a virus in that it requires tis-
sue culture for isolation, but like bacteria, it has both
DNA and RNA and is susceptible to some antimicro-
bial agents. Chlamydial infection exists in two morpho-
logically distinct forms during its unique life—a small
infectious elementary body and a large noninfectious
reticulate body. Much like a spore, the
elementary body
FIGURE 41-4.
Clue cells. Clue cells are epithelial cells with
clumps of bacteria clustered on their surface. Clue cells
indicate the presence of bacterial vaginosis. (From the Centers
for Disease Control and Prevention Public Health Image Library.
No. 3720. Courtesy of M. Rein.)
SUMMARY CONCEPTS
■■
Candidiasis, trichomoniasis, and bacterial
vaginosis are common vaginal infections that
become symptomatic because of changes in the
vaginal ecosystem.
■■
Candidiasis, also called a yeast infection, is a
frequent cause of vulvovaginitis. Candida can be
present without producing symptoms; usually
some host factor, such as altered immune status,
contributes to the development of vulvovaginitis.
■■
The manifestations of infection with Trichomoniasis
vaginalis, the causative agent of trichomoniasis,
are primarily observed in women, and range
from asymptomatic presentation to a copious,
frothy, malodorous green or yellow discharge.The
disorder is associated with pelvic inflammatory
disease, endometritis, infertility, and premature
labor. It has also been shown to facilitate human
immunodeficiency virus (HIV) infection.
■■
Bacterial vaginosis is a polymicrobial disorder
characterized by a lack of hydrogen peroxide–
producing lactobacilli and an overgrowth of
anaerobic organisms, including G. vaginalis,
Mobiluncus species, and M. hominis. It is the
most prevalent vaginal disorder in women of
reproductive age.The predominant symptom
of bacterial vaginosis is a thin, grayish-white
discharge that has a foul, fishy odor.
