The Vaginal Microbiome: II. Vaginal Dysbiotic Conditions

Abstract

This series of articles, titled The Vaginal Microbiome (VMB), written on behalf of the International Society for the Study of Vulvovaginal Disease, aims to summarize the recent findings and understanding of the vaginal bacterial microbiota, mainly regarding areas relevant to clinicians specializing in vulvovaginal disorders.Materials and Methods: A search of PubMed database was performed, using the search terms "vaginal microbiome" with "dysbiosis," "bacterial vaginosis," "cytolytic vaginosis," "desquamative inflammatory vaginitis," and "aerobic vaginitis." Full article texts were reviewed. Reference lists were screened for additional articles. Results:The second article in this series focuses on vaginal dysbiotic conditions. Dysbiosis is a term describing imbalances in bacterial communities. Given that lactobacillus-dominated microbiota are thought to be the most optimal, vaginal dysbiosis is usually considered as lactobacilli-depleted VMB. Bacterial vaginosis (BV), the most common vaginal dysbiotic condition, is a polymicrobial disorder, considered the leading cause for vaginal discharge in women worldwide. In addition, we review the VMB in other vaginal conditions associated with lactobacilli depletion: desquamative inflammatory vaginitis and aerobic vaginitis. We also discuss the controversial diagnosis of cytolytic vaginosis, related with lactobacilli overgrowth.Conclusions: Bacterial vaginosis displays complex microbiology. The heterogeneity and diversity within the genus Gardnerella may impact the progression of BV. Bacterial biofilms may contribute to the etiology and persistence of BV, and various bacteria may affect its clinical presentation and pathogenicity. Lack of lactobacilli is not always accompanied by an overgrowth of anaerobes.

High-Throughput Sequencing-Based Analysis of Changes in the Vaginal Microbiome during the Disease Course of Patients with Bacterial Vaginosis: A Case–Control Study

“…However, an excessive number of lactobacilli is associated with cytolytic vaginosis, and the state of various microbes during BV progression affects the clinical presentation and pathogenesis of the disease. Furthermore, the heterogeneity and diversity within the genus Gardnerella may impact BV progression [ 15 ].…”

Microbiological findings in prepubertal and pubertal girls with vulvovaginitis

“…BV differs from the rest of vaginal infections because usually, inflammation is not present. It is characterized by a shift in vaginal microflora with a significant decrease or even disappearance of lactobacilli and an increase in G. vaginalis , Atopobium vaginae , different anaerobic bacteria and a plethora of other microorganisms that cannot be cultured, and, as a result, their identification can be achieved only by molecular methods [ 29 , 30 ]. Furthermore, it has been demonstrated that BV is not only a polymicrobial infection but in fact a more complex clinical entity since it is characterized by biofilm formation [ 30 , 31 ], which could offer a possible explanation for the frequent recurrences observed [ 15 ].…”

“…It is characterized by a shift in vaginal microflora with a significant decrease or even disappearance of lactobacilli and an increase in G. vaginalis , Atopobium vaginae , different anaerobic bacteria and a plethora of other microorganisms that cannot be cultured, and, as a result, their identification can be achieved only by molecular methods [ 29 , 30 ]. Furthermore, it has been demonstrated that BV is not only a polymicrobial infection but in fact a more complex clinical entity since it is characterized by biofilm formation [ 30 , 31 ], which could offer a possible explanation for the frequent recurrences observed [ 15 ]. The increased prevalence of the microorganisms associated with BV in both our groups, although significantly increased in the pubertal group, is a matter of concern for future implications in their reproductive potential since BV has been associated with pelvic inflammatory disease (PID) and thus, with subfertility [ 32 ].…”

Optimal sampling and analysis methods for clinical diagnostics of vaginal microbiome

“…Lactobacilli protect women from pathogenic microbes. The development of imbalanced microbiota composition leads to a pathological condition called dysbiosis, a state which has been linked to various disorders and diseases typical for the urogenital tract [6][7][8][9][10]. For example, anaerobic bacteria such as Gardnerella, Atopobium, and Prevotella spp.…”