Genitourinary Tract Infections
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Vaginitis ( Diseases characterized by vaginal discharge)


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 is usually transmitted by sexual contact however; on rare occasions it can affect women who have never been sexually active. A recent Gallup survey found that very few women have a thorough understanding of vaginitis. While 95% of women surveyed had heard about yeast infections only 36 percent had ever heard of the MORE COMMON vaginal infection bacterial vaginosis (BV).


Bacterial Vaginosis (BV) is caused by Gardnerella vaginalis, Mycoplasma hominis and various anaerobic bacteria including Mobiluncus sp., and Prevotella 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 infections (STI’s).

Other organisms can cause vaginitis; Candida albicans (candidiasis) and Trichomonas vaginalis (trichomoniasis). These infections of the vagina are discussed in this section of the chapter as well.


Vaginal infections are often accompanied by vaginitis, which is an inflammation of the vagina characterized by discharge, irritation, and 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 (BV) is usually caused by Gardnerella vaginalis, Mycoplasma hominis and various anaerobic bacteria including Mobiluncus sp., and Prevotella sp.


Bacterial vaginosis is usually manifested as 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 noticeable around the time of menses. Vaginal itching or burning is also sometimes present. Up to 40% of women with BV may experience no outward symptoms. 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% more likely to deliver a low birth-weight baby (i.e., less than 5.5 lbs).



Bacterial vaginosis is caused by an overgrowth of bacteria rather than yeast or other organisms. These are primarily anaerobic bacteria and an organism called Gardnerella vaginalis, all of which can be found in low numbers in the healthy vaginal microflora. In women with BV, the vaginal balance is disrupted so that these bacteria overgrow at the expense of the protective bacteria; Lactobacillus. Lactobacilli produce hydrogen peroxide to help maintain a healthy and normal balance of microorganisms in the vaginal mucosa. Women who have been diagnosed with BV 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. The cause of this imbalance in the microflora of the vaginal mucosa is not currently known. Some studies have suggested that douching may be one cause of BV.


Three of four criteria should be positive to obtain a diagnosis of BV

Treatment and Prevention

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 the 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. If the patient has BV then it can be treated with the following:metronidazole or clindamycin

Mycotic Vulvovaginitis or Vulvovaginal Candidiasis


The causative agent of this disease is a yeast called Candida albicans.


The vaginal discharge frequently appears as a thick, curd like discharge containing epithelial cells and masses of hyphae/pseudohypha. The patient usually has intense pruritus of the vulva and erythematous vagina and labia.


Overgrowth with C albicans is the second most common cause of vaginitis.


When the delicate balance of organisms in the vagina is upset, the yeast can overgrow and cause vaginitis. 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, and prolonged exposure to moisture, and poor feminine hygiene.


Diagnosis is frequently made based on the character of the vaginal discharge (i.e., curd-like discharge) and on other patient signs and symptoms. Grams stains and KOH treatment of the discharge can be performed to look for yeast cells and pseudohyphae.

Treatment and Prevention

Intravaginal agents like butoconazole, clotrimazole, nystatin or terconazole can be given. An oral antifungal agent fluconazole can also be given to treat this disease.



The etiological agent is a flagellated protozoan Trichomonas vaginalis.  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.


In females proliferation of the organisms is associated with a low-grade inflammation manifested by: itching and burning, painful urination and a frothy, green, creamy discharge, which is described as being leukorrheic and very malodorous. Because of the ease of anatomic spread to the urethra, urethritis develops and is manifested chiefly by; dysuria and increased frequency and urgency. Many women with this infection may not have any symptoms.

In males symptoms can be associated with urethritis and prostatovesiculitis however men are usually asymptomatic. If symptoms exist they include: dysuria and increased frequency and urgency. Occasionally in severe cases there is exudate formation



Low-grade inflammation is associated with the presence of high numbers of trichomonads. This parasite attaches to the cells that line the surface of the vagina and produce proteases and cytotoxic toxins that cause the host cells to round up and detach. This damage results in an immunological response from the host with many PMN’s arriving at the mucosal surface of the vagina and in the vaginal discharge. These high numbers of trichomonads become established oftentimes because of a disruption of the normal flora that has allowed them to overgrow. Immunity to infection does occur but it is only partially protective against subsequent T vaginalis infections.


Clinical diagnosis depends upon recognition of the symptoms of dysuria, frothy, cream, malodorous discharges associated with punctate lesions and hyperemia of the vagina. The most practical method of specific diagnosis is microscopic examination for motile trichomonads in vaginal or urethral discharges. This vaginal discharge contains many PMN’s which usually are not present in the other causes of vaginitis.

Treatment and Prevention

Metronidazole is effective in treating this infection. Most men have asymptomatic T vaginalis infections and so can give back this parasite back to their female sexual partner. The use of male condoms can lower chances of transmission from an asymptomatic male to their female sexual partner. However, the best means of avoiding reinfection is to treat the male sexual partner with metronidazole.

Differential Diagnosis of Vaginal Infections

Diagnostic Criteria


Bacterial Vaginosis

Vaginitis Trichomonas

Candida Vulvovaginitis

Vaginal pH

3.8 - 4.2

> 4.5


< 4.5 (usually)


White, thin, flocculent

Thin, white (milky), gray

Yellow, green, frothy

White, curdy, "cottage cheese"

Amine odor
"whiff" test






epithelial cells

Clue cells, no WBC's

Trichomonads, WBC's >10/hpf

Budding yeast, hyphae, pseudohyphae

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

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

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:

E. Treatment of toxic shock syndrome

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

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

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.)

Pediculosis (crabs) Listeriosis

A. Etiology:

The disease is caused by the organism Listeria monocytogenes

B. Epidemiology C. Manifestations D. Pathology and pathogenesis E. Diagnosis F. Prognosis 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

B. Manifestations C. Diagnosis is difficult because it is a rare, usually unsuspected disease. 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:

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.

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Revised 1/19/10
©2010 Neal R. Chamberlain, Ph.D., All rights reserved.