Page 1 of 2
The bacterial vaginosis develops owing to substitution of normal microflora of a vagina, in particular the H2O2-producing lactobacilli, a large number of obligate and optional and anaerobic opportunistic microorganisms (Bacteroides, Prevotella, Peptococcus, Mobiluncus, Mycoplasma minis, etc.). In spite of the fact that the disease quite often develops at the persons having a large number of sexual partners and practically does not occur at the women who are not leading sex life, it does not belong to group of infectious diseases sexually transmitted. In this chapter is considered because the syndrome often occurs at sick STD.
The bacterial vaginosis represents a widespread clinical syndrome of women of reproductive age which identification frequency in group of sexually active women reaches 60%.
Etiology The reasons of development of a disease remain not clear, however there is a number of the factors influencing structure of microflora of a vagina.
Exogenous risk factors of development of a bacterial vaginosis:
• therapy by antibiotics, cytostatics, GKS, antiviral and antifungal medicines, radiation therapy;
• frequent washing of a vagina;
• malformations or anatomic defects after gaps in labor, surgical interventions, radiation therapy;
• foreign bodys in a vagina, a uterus (existence for a long time vulval pads or diaphragms, intrauterine spirals, etc.);
• use of spermitsid.
Internal causes of risk of development of a bacterial vaginosis:
hormonal changes at puberty, pregnancy, after the delivery and abortions;
disturbances of local immunity, decrease in quantity of the H2O2-producing lactobacilli and concentration of H2O2, hit of pathogenic microorganisms from a gastrointestinal tract.
Under the influence of adverse factors there is a disturbance of structure of microflora of a vagina. Reduction of quantity of lactobacilli leads to decrease in concentration of lactic acid and increase rn.
Anaerobic microorganisms adgezirutsya on an outer membrane of epithelial cells of a vagina that leads to formation of "key cells" and in total with transudation becomes the reason of emergence of allocations from a vagina.
Anaerobic microorganisms produce amino acids which are split to flying amines. Their education serves as the reason of emergence of an unpleasant smell of allocations.
Clinical signs and symptoms of an illness Main symptoms of a bacterial vaginosis:
• homogeneous allocations from a genital tract, it is frequent with an unpleasant smell, especially after sexual intercourse or in time and after periods. At the progressing course of a disease of allocation can get yellowish-greenish coloring, become more dense and evenly be distributed on vagina walls;
• in 20 — 30% of cases the itch and burning in external genitals, a dysuria, a dispareuniya are noted.
According to researches, at 24 — 32% of women the asymptomatic course of a bacterial vaginosis is noted.
The bacterial vaginosis can be the cause of failures of pregnancy. Besides, microorganisms which quantity increases at a bacterial vaginosis quite often become activators of infectious complications after the delivery or Cesarean section, and also inflammatory diseases of bodies of a small pelvis.
The diagnosis and the recommended clinical trials
The diagnosis is established in the presence of not less than 3 of the specified signs:
• the homogeneous allocations covering a mucous membrane of a vagina and a vulva;
• rn vulval exudate> 4,5;
• the positive aminotest (emergence of a "fish" smell when mixing on a slide plate vulval separated from 10% by potassium hydroxide in equal proportions);
• detection of "key" cells in native drug separated from a vagina.
Carrying out bacteriological research for O.'s identification is not recommended to vaginalis, and also polimerazny chain reaction as this activator often is found in healthy women. Bacteriological research is conducted for definition of species and quantitative composition of optional and anaerobic microflora of a vagina.
Differential diagnosis of a disease The differential diagnosis is carried out with other urogenital diseases caused pathogenic (N. gonorrhoeae, T. vaginalis, C. trachomatis) and opportunistic microorganisms.