How does a negative bacterial vaginosis test result occur?

According to statistics from gynecologists, vaginitis is now one of the diseases most common among women, and its incidence rate tends to increase with age. We all know that there are many types of vaginitis, including bacterial vaginitis, fungal vaginitis and so on. Among them, bacterial vaginosis is the most common. So, what is bacterial vaginosis? Today, let’s take a look at what causes bacterial vaginitis.

Endogenous infection. Bacterial vaginosis (BV) is generally not caused by a single pathogen, but the result of the combined action of multiple pathogens. BV is an endogenous infection caused by the disturbance of the ecological balance of the normal vaginal flora. In a normal vagina, lactobacilli that produce hydrogen peroxide are dominant. In bacterial vaginosis, the number of lactobacilli that produce hydrogen peroxide in the vagina decreases, while other microorganisms multiply in large numbers, mainly Gardnerella, anaerobic bacteria and Mycoplasma hominis, among which anaerobic bacteria are the majority. However, the initiating factors that trigger the transformation of normal vaginal flora and the development of BV are still unclear.

Pathogenesis. Lactobacillus, especially hydrogen peroxide-producing lactobacillus, is critical to maintaining the normal ecological environment of the vagina. When it is significantly reduced or disappears, Gardnerella, anaerobic bacteria, Bacteroides, and Mycoplasma hominis will proliferate. The number of these microorganisms can increase by 100 to 1000 times, resulting in a decrease in lactate concentration and an increase in amines, including cytotoxins, sialidase, mucopolysaccharidase and collagenase, an increase in amines (cadaverine, putrescine, trimethylamine), organic acids and some enzymes (mucopolysaccharidase, sialidase, phospholipase, IgA protease, etc.), which can increase vaginal secretions and produce a foul odor. The pathogens of BV can produce virulence factors that cause epithelial cell damage, resulting in fluid exudation and shedding of vaginal squamous epithelial cells, producing typical BV secretions.

Bacteria such as Gardnerella attach to the desquamated vaginal epithelial cells to form clue cells. When the biochemical composition of vaginal secretions changes accordingly, the pH value increases. The alkaline environment is not conducive to the adhesion and growth of Lactobacillus, but is conducive to the growth of anaerobic bacteria such as Gardnerella, thereby causing bacterial vaginosis. The incidence rate is high in pregnant women, suggesting that it is related to estrogen levels. Its pathological characteristics include the absence of inflammatory lesions and leukocyte infiltration. Enzymes and organic acids can destroy the host's defense mechanisms, such as dissolving cervical mucus, which can promote the entry of microorganisms into the upper reproductive tract and cause upper reproductive tract inflammation.

The above are the causes of bacterial vaginosis, which is caused by infection with multiple bacteria, resulting in inflammation of the vagina. Many people are afraid and worried when they hear about bacterial vaginosis; because they seldom hear about it, they think it is very serious when they hear about bacteria. In fact, paying more attention to personal hygiene and keeping the lower body fresh and clean can play a good preventive role.