Genitourinary
Tract Infections
Return to Syllabus
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VAGINITIS
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TOXIC SHOCK SYNDROME
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SCABIES
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PEDICULOSIS
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VIBRIONIC ABORTION
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PUERPERAL FEVER
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LISTERIOSIS
Vaginitis
Overview
Vaginal infections are the most common women's health problem, and have
been increasingly linked to a growing array of serious health risks. Vaginal
infections, known medically as vaginitis, are the most frequent reason
American women see their doctors--accounting for more than 10 million office
visits each year. Some vaginal infections are transmitted through sexual
contact (Trichomoniasis), but others such as candidiasis (yeast infections)
are not. Bacterial vaginosis can be transmitted by sexual contact however,
overgrowth of certain of the bacteria (see below) in the vagina can
also result in a case of vaginitis.
A recent Gallup survey found that very few women have a thorough understanding
of vaginitis. While 95 percent of women surveyed had heard about yeast
infections only 36 percent had ever heard of a more common vaginal infection
called bacterial vaginosis (BV).
Etiology
Bacterial Vaginosis (BV) due to Gardnerella vaginalis, Mycoplasma
hominis and various anaerobic bacteria including
Mobiluncus
sp., and Bacteroides sp.
BV is the most common vaginal infection. The disease
has been found in 12 to 25 percent of women in routine clinic populations,
10 to 26 percent of women in obstetrics clinics and 32 to 64 percent of
women in clinics for sexually transmitted diseases (STDs).
Other organisms can cause vaginitis. Candida albicans (Candidiasis)
and Trichomonas vaginalis (Trichomoniasis). These infections
of the vagina are discussed in this handout as well.
Manifestations
Vaginal infections are often accompanied by vaginitis, which is an inflammation
of the vagina characterized by discharge, irritation, and/or itching. The
cause of vaginitis cannot be adequately determined solely on the basis
of symptoms or a physical examination. Laboratory tests allowing microscopic
evaluation of vaginal fluid are required for a correct diagnosis. A variety
of effective drugs are available for treating vaginal infections and accompanying
vaginitis.
Bacterial Vaginosis
A. Etiology
Bacterial Vaginosis (BV) due to Gardnerella vaginalis, Mycoplasma
hominis and various anaerobic bacteria including
Mobiluncus
sp., and Bacteroides sp.
B. Epidemiology
Bacterial vaginosis (BV) is the most common cause of vaginitis symptoms
among women of childbearing age. BV--previously called nonspecific vaginitis
or Gardnerella-associated vaginitis-- can be transmitted through
sexual activity, although the organisms responsible also have been found
in young women who are not sexually active.
Bacterial vaginosis is caused by an overgrowth of bacteria rather than
yeast or other organisms. These are primarily anaerobic bacteria (requiring
no oxygen) and an organism called Gardnerella, all of which can
be found in low numbers in the healthy vagina. In women with BV, the vaginal
balance is disrupted so that these bacteria overgrow at the expense of
protective bacteria known as lactobacilli. Lactobacilli excrete hydrogen
peroxide to help maintain a healthy and normal balance of microorganisms
in the vagina. Women who have been diagnosed with BV have been found to
have up to 1,000 times more anaerobic bacteria than women without the disease.
Instead of the normal predominance of Lactobacillus bacteria, increased
numbers of organisms such as Gardnerella vaginalis, Bacteroides, Mobiluncus,
and Mycoplasma hominis are found in the vagina in women with BV.
A few studies have also correlated BV with increased douching, an increased
number of sexual partners and use of intrauterine devices. While sexual
activity may increase the likelihood of developing BV, the condition has
also been found in sexually inexperienced and monogamous women.
C. Manifestations
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An unpleasant vaginal odor in varying degrees and an excessive white or
gray vaginal discharge with a milk-like consistency. Women often report
that the odor is particularly embarrassing after sexual intercourse. When
semen mixes with vaginal secretions, it lowers the acidity level to make
the odor particularly strong. Odor may also be more noticable around the
time of menses.
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Vaginal itching or burning are also sometimes present.
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Up to 40 percent of women with BV may experience no outward symptoms
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BV has been associated with pelvic inflammatory disease, which can result
in infertility, as well as increased risk of endometritis, cervicitis,
pregnancy complications, and post-operative infections. Pregnant women
with BV in the 23rd to 26th weeks of pregnancy were 40 percent more likely
to deliver a low birth-weight baby (less than 5.5 lbs).
B. Diagnosis
Three of the four criteria should be positive
C. Treatment,
Products like douches or deodorant sprays that mask vaginal odor should
not be used to treat BV. Although they may temporarily eliminate odor,
they will not cure the condition. It is important to tell your patient
not to douche or use a feminine hygiene spray for a few days before their
appointment. These products may actually hide important clues that can
help in diagnosing BV, and may make the condition worse.
antibiotic therapy: metronidazole or clindamycin for 7 days.
BARBARA A. MAJERONI, M.D., 1998. Bacterial
Vaginosis: An Update. American Family Physician. March 15, 1998.
http://www.aafp.org/afp/980315ap/majeroni.html
Mycotic vulvovaginitis or vulvovaginal candidiasis
1. Epidemiology
Overgrowth with C. albicans is actually the second most
common cause of vaginitis.
When the delicate balance of organisms in the vagina is upset, the yeast
may overgrow and cause vaginitis. For example, when a woman takes certain
antibiotics to treat a bacterial infection, the antibiotic may also kill
the lactobacilli that produce hydrogen peroxide to protect against yeast
overgrowth. Other factors that may upset the balance and lead to yeast
infection include pregnancy, obesity, diabetes, birth control pills, steroids,
prolonged exposure to moisture and poor feminine hygiene.
2. Manifestations
3. Diagnosis
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evaluation of symptoms and clinical setting
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Gram stains of exudates (image 1
and
2)
4. Therapy
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Nystatin for 2 weeks OR
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Miconazole nitrate 2% vaginal cream, one applicator full, intravaginally
at bedtime for 7 days OR
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Clotrimazole, 1 vaginal suppository daily for 7 days
Trichomoniasis
A. Etiology
The etiological agent is a flagellated protozoan Trichomonas
vaginalis.
1. Morphology
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It is a pear shaped organism exhibiting a characteristic motility described
as a wobbling and rotating motion, recognition of this on wet mounts is
important in diagnosis.
B. Epidemiology
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T. vaginalis is a common parasite of both males and females and
the incidence is in part related to hygiene.
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Intercourse is the usual method of transmission, especially via asymptomatic
males.
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In rare instances it may be passed on by wet towels, washcloths and
bathing suits
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The infection often persists because the parasite rarely causes symptoms
in men, so that reinfection of women by untreated men is common.
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Some women can be infected for months to years as the infection is passed
back and forth between the woman and her sexual partner. For this reason,
both sexual partners must be treated at the same time, even if they are
in a monogamous relationship.
C. Manifestations
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Vaginitis and urethritis in females
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Disruption of normal flora organisms in vagina may alter pH (>4.5) and
other factors which allow T. vaginalis to overgrow.
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Proliferation of the organisms is associated with a low grade inflammation
manifested by:
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Because of the ease of anatomic spread to the urethra, urethritis develops;
again it is manifested chiefly by
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Dysuria
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Frequency and urgency
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many women with this infection may not have any symptoms
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Urethritis and prostatovesiculitis in males is usually asymptomatic but
may be manifested by:
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Dysuria
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Urgency and frequency
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Occasionally in severe cases there is exudate formation
D. Pathology
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Low grade inflammation is associated with the presence of high numbers
of trichomonads.
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These high numbers of trichomonads become established because something
has disrupted the normal flora and allowed them to overgrow.
E. Diagnosis
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Clinical diagnosis depends upon recognition of the symptoms of dysuria,
frothy, cream, malodorous discharges associated with punctate lesions and
hyperemia of the vagina - highly suggestive.
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The most practical method of specific diagnosis is microscopic examination
for motile trichomonads in vaginal or urethral discharges.
F. Treatment
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Oral metronidazole, single dose -- supplement with vaginal insert for 10
days in women.
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Don't treat pregnant females with this until they deliver because of potential
harmful effects on the developing fetus.
Differential Diagnosis of Vaginal Infections
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Diagnostic Criteria
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Normal
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Bacterial Vaginosis
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Vaginitis Trichomonas
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Candida Vulvovaginitis
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Vaginal pH
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3.8 - 4.2
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> 4.5
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4.5
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< 4.5 (usually)
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Discharge
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White,thin, flocculent
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Thin, white (milky), gray
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Yellow, green, frothy
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White, curdy, "cottage cheese"
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Amine odor
"whiff" test
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Absent
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fishy
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fishy
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Absent
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Miroscopic
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Lactobacilli,
epithelial cells
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Clue cells, adherent cocci, no WBC's
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Trichomonads, WBC's >10/hpf
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Budding yeast, hyphae, pseudohyphae
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Toxic shock syndrome
is an acute systemic illness associated with infection by toxic shock syndrome
toxin (TSST) producing strains of Staphylococcus aureus (phage group
I).
A. Epidemiology
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Seen most commonly in women, coincident with the onset of menstruation.
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Predisposing factors include use of hyperabsorbable tampons.
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Localized infections with TSST-1 producing strains of S. aureus
can also cause TSS. This disease can occur in men as well as women.
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The case fatality rate is approximately 3.3% and there are approximately
150 cases per year.
B. Pathology
Is due to the production of TSST-1. This toxin is a superantigen. Superantigens
bind to and activate T helper cells. As many as 20% of the T helper cell
can be activated. When activated they produce Interleukin 2 and other cytokines
that cause the symptoms of TSS. The bacteria do not usually invade the
tissues or the bloodstream. This is usually the result of an intoxication
with TSST-1.
C. Manifestations
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Fever (> 40°C), vomiting, diarrhea, and myalgias
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Hypotension (< 90 mm Hg) due to hypovolemia
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Diffuse, "sunburn like" erythematous rash (mostly on trunk, less on extremities),
which characteristically undergoes desquamation.
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Conjunctival and vaginal hyperemia
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Signs of uremia
D. Diagnosis:
Toxic shock syndrome should be considered in cases involving unexplained
fever associated with an erythematous rash and diffuse organ involvement,
especially in menstruating women. Diagnostic criteria include:
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Fever > 38.9°C
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< 90 mm Hg systolic pressure
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Rash with subsequent desquamation (especially palms and soles)
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Involvement of > 3 organ systems
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Gastrointestinal (vomiting and diarrhea)
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Muscular (severe myalgias)
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Mucous membranes (hyperemia)
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Renal insufficiency (BUN and creatine and pyuria)
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Liver (hepatitis with bilirubin, SGOT and SGPT 2x normal)
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Blood (thrombocytopenia)
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CNS (disorientation without focal neurologic signs)
E. Treatment of toxic shock syndrome
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Aggressive fluid replacement
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Beta lactamase resistant antibiotics (oxacillin or nafcillin) I.V.
Toxic Shock Syndrome caused by Streptococcus pyogenes
A. Etiology
S. pyogenes M types 1 and 3 producing streptococcal pyogenic
exotoxin A (Spe A).
B. Epidemiology
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As the result of a minor trauma, the organisms enter the body.
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About 50-100 cases/year.
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Case Fatality rate = 30-70%.
C. Pathology
Is due to the production of streptococcal pyrogenic exotoxin A (Spe
A toxin). This toxin is a superantigen. Superantigens bind to and activate
T helper cells. As many as 20% of the T helper cell can be activated. When
activated they produce Interleukin 2 and other cytokines that cause the
symptoms of streptococcal TSS. In this case the bacteria invade the tissues
and/or the patient's bloodstream as well as produce Spe A.
D. Case definition
1. Isolation of group A streptococcus
a. From sterile site.
b. From non-sterile site.
2. Clinical signs of severity
a. Hypotension
b. Two or more clinical
and laboratory abnormalities (see below)
Definite case = 1a and 2 (a and b)
Probable case = 1b and 2 (a and b)
Clinical and laboratory abnormalities
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Renal impairment
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Coagulopathy
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Liver abnormalities
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Acute respiratory distress syndrome
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Extensive tissue necrosis
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Erythematous rash
D. Treatment
Aggressive fluid replacement, Beta lactam antibiotics or clindamycin
Miscellaneous others
Scabies - mite infestation
(sarcoptes
scabiei, excellent image from Jens G. Mattsson,
MSc. Ph.D.)
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Causes itching (especially at night), mite
burrows into skin.
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Dx
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Grossly or microscopically demonstrate
mite, its eggs, larvae, or feces.
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India Ink placed on skin can be used to detect where the organisms burrow
in the skin.
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Demonstrate lesion pruritic, erythematous,
papular eruptions.
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Typical clinical presentation.
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Treatment
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Permethrin cream (5%) applied to all areas of the body from the neck down
and washed off after 8-14 hours.
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Lindane (1%) 1 oz. of lotion or 30 g of cream applied thinly to all areas
of the body from the neck down and thoroughly washed off after 8 hours.
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Sulfur (6%) precipitated in ointment applied thinly to all areas nightly
for 3 nights. Previous applications should be washed off before new applications
are applied. Thoroughly wash off 24 hours after the last application.
Pediculosis (crabs)
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Caused by lice (pediculosis pubis,
image
2)
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Dx
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Finding lice or nits
attached
to genital hairs (definitive Dx)
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Patient with a history of pubic lice presents with pruritic erythematous
papules (presumptive Dx).
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Treatment
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Permethrin 1% creme rinse applied to affected areas and washed off after
10 minutes. OR
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Lindane 1% shampoo applied for 4 minutes to the affected area, and then
thoroughly washed off. This regimen is not recommended for pregnant or
lactating women or for children aged less than 2 years. OR
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Pyrethrins with piperonyl butoxide applied to the affected area and washed
off after 10 minutes.
Listeriosis
A. Etiology:
The disease is caused by the organism Listeria monocytogenes
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They are small Gram- to Gram variable rods; they are motile by means of
peritrichous flagella and are said to exhibit a characteristic end-over-end
tumbling motion at 22°C.
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Physiology
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They grow well and exhibit Beta-hemolysis; they are frequently best isolated
on blood agar following cold enrichment techniques (4°C for 48 hours
before plating). they exhibit a tumbling motility at room temperature.
B. Epidemiology
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This organism can be isolated from soil, water, vegetation, and a variety
of mammals, birds, insects, fish, and other animals.
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Listeriosis is transmitted via the placenta to the fetus and is ingested
in contaminated foods (e.g. contaminated milk, soft cheese, undercooked
meat, unwashed raw vegetables, and cabbage).
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Most healthy adults have no symptoms of infections. 1 to 5% of adults are
healthy asymptomatic human carriers.
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Peak attack rates occur at ages less than 1 year and between the ages of
55- 64. When disease is manifested it is in the very young, elderly, pregnant
women, and people with defective cell-mediated immunity.
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There are 12.4 cases of invasive human disease per 100,000 live births
and 7.4 cases per million population.
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The incidence of listeriosis in AIDS patients is 100 times greater.
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4th most common cause of community-acquired meningitis
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The mortality rate (20-30%) of symptomatic listerosis is higher that almost
all other foodborne diseases.
C. Manifestations
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Early onset disease or granulomatosis infantiseptica: prenatal listeria
septicemia
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Results from a low grade uterine infection of the mother; the infection
spreads to the fetus and causes severe disease.
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Results in abortion, premature delivery, stillbirth or death within a few
days.
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severe cardiovascular distress
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vomiting
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diarrhea
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maculopapular skin lesions on legs and trunk
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severe meningitis resulting in coma and death
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generally the mother is totally asymptomatic during pregnancy.
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high mortality rate unless treated.
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Post natal infection in both age groups results in a severe meningitis
or meningoencephalitis with septicemia that has a 70% mortality rate associated
with it.
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Adults:
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asymptomatic or mild flu-like symptoms
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meningitis
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bacteremia
D. Pathology and pathogenesis
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Although L. monocytogenes is ubiquitous, and is transmitted via
the placenta to the fetus and is ingested in contaminated foods (e.g. contaminated
milk, soft cheese, undercooked meat, unwashed raw vegetables, and cabbage).
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Meningeal localization is the most common clinical form of listeriosis;
it is pathologically similar to other forms of pyogenic meningitis.
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All virulent strains produce a toxin called listeriolysin O.
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It exists in humans as a intracellular pathogen that can grow in macrophages
and epithelial cells.
E. Diagnosis
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Diagnosis depends upon isolation of the organism L. monocytogenes.
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Alert the laboratory if you suspect it because the isolation may be a slow,
drawn out affair.
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Serodiagnosis is complicated because of low levels of natural agglutinins.
F. Prognosis
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It has a 90% fatality rate if untreated.
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Infected neonates die with or without treatment, particularly if infected
for some time in utero.
G. Recommended therapy and prevention:
A combination of penicillin G and gentamicin.
High risk people should avoid eating raw or partially cooked foods of
animal origin, soft cheese, and unwashed raw vegetables.
Vibrionic abortion (vibriosis)
is an infectious disease caused by the organism Vibrio fetus.
A. Epidemiology
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Vibriosis is primarily a venereal disease of cattle, sheep and goats.
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Man usually acquires the disease from direct contact with infected livestock,
although the portal of entry is poorly defined (probably orally).
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In cases involving abortion, it is thought that an asymptomatic male transmits
the disease to a pregnant sex partner and the organism transcends the placenta
to infect the fetus.
B. Manifestations
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Fever is the most common manifestation in adults, although it may be complicated
by endocarditis, thrombophlebitis, septic arthritis or osteomyelitis.
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In infants it usually presents as a fulminating, lethal meningoencephalitis.
C. Diagnosis is difficult because it is a rare, usually unsuspected
disease.
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Vibriosis should be suspected in cases involving obscure febrile conditions
associated with thrombophlebitis or abortion and/or premature delivery
in pregnant women.
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The diagnosis is confirmed by microscopic demonstration of the comma-shaped
bacteria in Gram strains of clinical isolates, followed by agglutination
tests with specific anti-vibrio antibodies.
Puerperal fever
is an infectious disease associated with childbirth and results from infection
of the mother and/or fetus with various strains of streptococci.
A. Etiology
Both Group A and Group B streps are responsible.
B. Pathogenesis
In the mother the streptococci invade the endometrium and lymphatics
to result in bacteremia.
C. Manifestations include:
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High irregular fever, chills
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Tachycardia
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Leukocytosis
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Foul smelling vaginal discharge
Infants generally present within 48 hours of birth with systemic sepsis
manifested primarily by signs of respiratory distress.
It may take up to 60 days to become manifest in the infant and then
it is usually as a meningitis.
It is a disease of great historical significance but it is much less
common due to greater sterility precautions during the birth process.
D. Treat with ampicillin.
Send comments and mail to Dr. Neal R. Chamberlain, nchamberlain@kcom.edu
Revised 8/7/02
©2002 Neal R. Chamberlain, Ph.D., All rights reserved.