Smear test on the flora in gynecology (cervical screening)November 30, 2017
Smear examination of the vagina and cervix
Microscopic (bacterioscopic) smear examination in gynecology is conducted to determine the nature of the microflora of the urogenital tract. Biomaterial for microscopy is a detachable (scraping) out of the urethra, vagina and cervical canal, which is examined under a microscope with or without a preliminary staining of the smear (native smear).
Microscopic examination of the smear is widely used in the course of dispensary gynecological examinations, as well as for the diagnosis of inflammatory processes of the genitourinary sphere.
When microscopic examination of the smear is determined by the number and ratio of normal, opportunistic and pathogenic microorganisms, as well as cellular elements, on the basis of which a conclusion is made about the nature of the microflora, the presence and severity of the inflammatory process. In the smear on the flora, the presence of lactobacilli, the amount of epithelium, leukocytes and erythrocytes, the presence or predominance of opportunistic and pathogenic flora is estimated.
Indication and preparation for cervical screening
Microscopy (smear microscopy) is carried out practically healthy women with planned gynecological examinations, pregnant women in I and III trimesters, with a suspicion of infectious and inflammatory diseases of the genitourinary sphere and bacterial vaginosis.
Preparation for delivery of a smear on the flora consists in stopping the use of vaginal suppositories, antibacterial intimate means, exclusion of douching and sexual life 36 hours prior to the study. On the eve of taking a smear, it is allowed to hold the toilet only of the external genitalia, it is not recommended to urinate 2-3 hours before the analysis.
The most favorable time for delivery of a smear is 5-7th day after menstruation, during a monthly smear it is not carried out.
For the preparation of smears, 2 slides, previously degreased with ether or alcohol and dried, are taken. With a special pencil, each glass is divided into 3 parts, on the back of which the notations “U” – urethra, “C” – cervix and “V” vagina are placed.
A smear on the flora is taken by a gynecologist before carrying out manual examination, colposcopy, vaginal treatment procedures and other manipulations.
First, a smear from the urethra is taken, for which the finger inserted into the vagina, it is lightly massaged. The first portion of discharge from the urethra should be removed with a cotton ball, then insert into the urethra to a depth of 1.5-2 cm a disposable spatula or a sterile Volkmann spoon.
The material for examination from the urethra is obtained by lightly scraping and applied as a circle on 2 slides marked “U”.
Then a gynecological mirror is inserted into the vagina, the cervix is exposed, the cervix is rubbed with a cotton ball, and a smear from the cervical canal is aimed at the same way as from the urethra.
A slight scraping of the mucosa is necessary in order that gonococci, usually located under the epithelial cover, enter the test material. After this, take the discharge from the posterior vaginal vault. The obtained material from the cervix and vagina is applied to slide glasses with the appropriate marking in the form of a stroke. The smears are dried in air and sent to a laboratory for microscopy.
Smears from different places should be taken only by separate sterile instruments. It is incorrect to take a material with a glove, a mirror, after a two-handed examination, etc. The resulting material should be spread over the slide in a wide thin smear. With the observance of the rules for taking the smear the procedure is painless.
In the laboratory, smears on one glass are stained with mytilene blue, on the other – by Gram and subjected to examination under a microscope. When smearing a smear from the posterior vaginal fornix, the purity of the vaginal contents is determined, smears from the cervix and urethra are examined for flora and gonococci.
Normally, the smear should contain squamous epithelial cells lining the cervix and vagina. The absence of flat epithelial cells may indicate a lack of estrogens and an excess of androgens in the body of a woman or about the atrophy of the epithelial layer. Also a normal smear on the flora contains leukocytes – up to 10-15 units in the field of view.
An increased number of leukocytes is observed with inflammation of the vagina – colpitis: the more in the smear of leukocytes, the more acute the phase of the disease.
It is considered the norm in the presence of a smear of Staphylococcus aureus in small amounts. A significant increase in staphylococcal flora, as well as leukocytes, may be a sign of inflammatory processes in the vagina or mucous membrane of the uterus (endometritis). The normal microflora of the vagina includes lactobacilli (Dederlein sticks), except for them, the smear should not contain other microorganisms.
The presence of foreign microorganisms (streptococci, pneumococci, staphylococci, enterococci, gonococcus, chlamydia infection, anaerobes, yeast fungi, protozoa, etc.) in the smear indicates the presence of infection of the urogenital tract.
When the smear deviates from the norm, patients undergo additional smear tests using PCR, ELISA, and bapsose. Microscopic examination of the smear is performed within 1 day, express method – within 15 minutes.
Smear test of vagina and cervix: Interpretation of results
In accordance with the nature of microflora, gynecology distinguishes several degrees of purity of vaginal contents, reflecting the ratio of normal, opportunistic and pathogenic flora:
- I degree of purity is characterized by an acidic environment and the presence in the vaginal contents of only Dederlein sticks and individual epithelial cells.
- At the II degree of purity, the number of vaginal bacilli decreases, a small amount of saprophytes appears, individual cocci and single white blood cells, the vaginal environment remains acidic. I and II degree of purity are considered the norm.
- With the third degree of purity in the vaginal content, leukocytes, cocci and other bacteria predominate, the reaction with acid changes to alkaline.
- IV degree of purity is characterized by the absence of vaginal sticks and the detection of various microbial flora, mainly pathogenic (cocci, Escherichia coli, Trichomonads, etc.), a large number of leukocytes. III and IV degrees of purity create favorable conditions for the development of pathological processes.
Evaluation of the results of a microscopic examination of the smear is performed by a gynecologist, taking into account the history and the presence of clinical manifestations. The reliability of the results of microscopy depends on the correctness of the preparation and technique of taking and testing the smear.