Vaginal wet mount
Encyclopedia
A vaginal wet mount is a gynecologic test wherein a sample of vaginal discharge
is observed by wet mount microscopy by placing the specimen on a glass slide and mixing with a salt solution. It is used to find the cause of vaginitis
and vulvitis
.
and bacterial vaginosis
.
Infections such as chlamydia, genital warts, syphilis
, herpes simplex
, and gonorrhea
can also affect the vagina, but these diseases are found by doing other tests.
It may also be used in a rape investigation
to detect presence of semen
.
A vaginal wet mount is not done during the menstrual period, because menstrual blood on the slide can confound the results. Vaginal irrigation, tampon use or sex (potentially disrupting the vaginal pH
) should be avoided for 24 hours before the test. Vaginal medicines (such as a nonprescription vaginal yeast medicine) should not be used during the 2 to 3 days before the test.
The sampling is done with the patient in lithotomy position
. A speculum
is used to facilitate use of a swab or spatula to sample fluid inside the vagina. The sampling procedure may cause some discomfort and minor bleeding, but otherwise there are no associated risks. The sample is then smeared upon a microscope slide
and is observed by wet mount microscopy by placing the specimen on a glass slide and mixing with a salt solution.
s are found on the slide. White blood cells are normally absent or very low in number.
Furthermore, presence of white blood cells is a general sign of infection.
If indicated, the sample can also be used for:
Vaginal discharge
Vaginal discharge is term given to biological fluids contained within or expelled from the vagina.While most discharge is normal and can reflect the various stages of a woman's cycle, some discharge can be a result of an infection, such as a sexually transmitted disease.The term blennorrhea is...
is observed by wet mount microscopy by placing the specimen on a glass slide and mixing with a salt solution. It is used to find the cause of vaginitis
Vaginitis
Vaginitis is an inflammation of the vagina. It can result in discharge, itching and pain, and is often associated with an irritation or infection of the vulva. It is usually due to infection. The three main kinds of vaginitis are bacterial vaginosis , vaginal candidiasis, and trichomoniasis. A...
and vulvitis
Vulvitis
Vulvitis is a condition of inflammation of the vulva of a female.Vulvitis is inflammation of the external genital organs of the female . The vulva includes the labia, clitoris, and entrance to the vagina . An inflammation of the vulva is referred to as vulvitis. Vulvitis, like vaginitis, may be...
.
Indication
A vaginal wet mount may be considered in case of vaginitis symptoms such as vaginal itching, burning, rash, odor, or discharge. It may assist in suspicion of vaginal yeast infection, trichomoniasisTrichomoniasis
Trichomoniasis, sometimes referred to as "trich", is a common cause of vaginitis. It is a sexually transmitted disease, and is caused by the single-celled protozoan parasite Trichomonas vaginalis producing mechanical stress on host cells and then ingesting cell fragments after cell death...
and bacterial vaginosis
Bacterial vaginosis
Bacterial vaginosis or less commonly vaginal bacteriosis is a disease of the vagina caused by bacteria. The U.S. Centers for Disease Control and Prevention states it is not clear what role sexual activity plays in the development. However, it is known that BV is associated with having a new sex...
.
Infections such as chlamydia, genital warts, syphilis
Syphilis
Syphilis is a sexually transmitted infection caused by the spirochete bacterium Treponema pallidum subspecies pallidum. The primary route of transmission is through sexual contact; however, it may also be transmitted from mother to fetus during pregnancy or at birth, resulting in congenital syphilis...
, herpes simplex
Herpes simplex
Herpes simplex is a viral disease caused by both Herpes simplex virus type 1 and type 2 . Infection with the herpes virus is categorized into one of several distinct disorders based on the site of infection. Oral herpes, the visible symptoms of which are colloquially called cold sores or fever...
, and gonorrhea
Gonorrhea
Gonorrhea is a common sexually transmitted infection caused by the bacterium Neisseria gonorrhoeae. The usual symptoms in men are burning with urination and penile discharge. Women, on the other hand, are asymptomatic half the time or have vaginal discharge and pelvic pain...
can also affect the vagina, but these diseases are found by doing other tests.
It may also be used in a rape investigation
Rape investigation
Rape investigation is the procedure to gather facts about a suspected rape, including forensic identification of a perpetrator, type of rape and other details....
to detect presence of semen
Semen
Semen is an organic fluid, also known as seminal fluid, that may contain spermatozoa. It is secreted by the gonads and other sexual organs of male or hermaphroditic animals and can fertilize female ova...
.
Method
Having sex within 24 hours before the test can affect the vaginal pH.A vaginal wet mount is not done during the menstrual period, because menstrual blood on the slide can confound the results. Vaginal irrigation, tampon use or sex (potentially disrupting the vaginal pH
PH
In chemistry, pH is a measure of the acidity or basicity of an aqueous solution. Pure water is said to be neutral, with a pH close to 7.0 at . Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline...
) should be avoided for 24 hours before the test. Vaginal medicines (such as a nonprescription vaginal yeast medicine) should not be used during the 2 to 3 days before the test.
The sampling is done with the patient in lithotomy position
Lithotomy position
The lithotomy position is a medical term referring to a common position for surgical procedures and medical examinations involving the pelvis and lower abdomen, as well as a common position for childbirth in Western nations...
. A speculum
Speculum
The term speculum, Latin for "mirror", and its plural specula, may refer to:* Speculum , a medical tool used for examining body cavities* Speculum , a journal of medieval studies published by the Medieval Academy of America...
is used to facilitate use of a swab or spatula to sample fluid inside the vagina. The sampling procedure may cause some discomfort and minor bleeding, but otherwise there are no associated risks. The sample is then smeared upon a microscope slide
Microscope slide
A microscope slide is a thin flat piece of glass, typically 75 by 25 mm and about 1 mm thick, used to hold objects for examination under a microscope. Typically the object is placed or secured on the slide, and then both are inserted together in the microscope for viewing...
and is observed by wet mount microscopy by placing the specimen on a glass slide and mixing with a salt solution.
Interpretation
Normally, there are no yeast, bacteria, trichomoniasis, or clue cellClue cell
Clue cells are epithelial cells of the vagina that get their distinctive stippled appearance by being covered with bacteria.They are a medical sign of bacterial vaginosis, particularly that caused by Gardnerella vaginalis, a group of Gram-variable bacteria...
s are found on the slide. White blood cells are normally absent or very low in number.
- A vaginal yeast infection often causes a white, lumpy discharge that looks like cottage cheese.
- TrichomoniasisTrichomoniasisTrichomoniasis, sometimes referred to as "trich", is a common cause of vaginitis. It is a sexually transmitted disease, and is caused by the single-celled protozoan parasite Trichomonas vaginalis producing mechanical stress on host cells and then ingesting cell fragments after cell death...
causes a vaginal discharge that is yellow-green, foamy, and bad-smelling. - Bacterial vaginosisBacterial vaginosisBacterial vaginosis or less commonly vaginal bacteriosis is a disease of the vagina caused by bacteria. The U.S. Centers for Disease Control and Prevention states it is not clear what role sexual activity plays in the development. However, it is known that BV is associated with having a new sex...
generally produces a vaginal discharge that is thin and milky with a strong fishy odor. Besides, clue cellClue cellClue cells are epithelial cells of the vagina that get their distinctive stippled appearance by being covered with bacteria.They are a medical sign of bacterial vaginosis, particularly that caused by Gardnerella vaginalis, a group of Gram-variable bacteria...
s may be seen in bacterial vaginosis.
Furthermore, presence of white blood cells is a general sign of infection.
Concomitant vaginal discharge tests
A vaginal discharge sample wet mount is often also used for the following additional tests:- KOH slideKOH testThe KOH Test for Candida albicans, also known as a potassium hydroxide preparation, is a quick, inexpensive fungal test to differentiate between dermatophytes and Candida albicans symptoms from other skin disorders like psoriasis and eczema....
. A sample of the vaginal discharge is placed on a slide and mixed with a solution of potassium hydroxidePotassium hydroxidePotassium hydroxide is an inorganic compound with the formula KOH, commonly called caustic potash.Along with sodium hydroxide , this colorless solid is a prototypical strong base. It has many industrial and niche applications. Most applications exploit its reactivity toward acids and its corrosive...
(KOH). The KOH kills bacteria and cells from the vagina, leaving only yeast for easier detection of a yeast infection. Several drops of a potassium hydroxide (KOH) solution may also be added to a sample of the vaginal discharge to test for any resultant strong fishy odor from the mix, which would indicate bacterial vaginosis. The latter procedure is called a Whiff test. - Vaginal pH test. The normal vaginal pH is 3.8 to 4.5. Bacterial vaginosis, trichomoniasis, and atrophic vaginitis often cause a vaginal pH higher than 4.5.
If indicated, the sample can also be used for:
- Detecting atrophic vaginitisAtrophic vaginitisAtrophic vaginitis is an inflammation of the vagina due to the thinning and shrinking of the tissues, as well as decreased lubrication...
by additional staining. - Vaginal culture, to see if bacteria, yeast, or trichomonads will grow.