Quantification of Gardnerella vaginalis, Atopobium vaginae and Lactobacillus spp. in bacterial vaginosis

Abstract

Introduction: The aim of the study was to investigate prevalence of bacteria most frequently associated with bacterial vaginosis using Amsel’s criteria as well as to quantify these bacteria by real-time PCR and to explore the difference in their quantity between healthy and bacterial vaginosis samples.
 Methodology: For classification of vaginal discharge samples Amsel’s criteria have been used. To detect and quantify Gardnerella vaginalis Atopobium vaginae, Lactobacillus spp. and total vaginal microbiome, real-time PCR has been applied.
 Results: According to results of our study Amsel’s criteria matched well with real-time PCR diversification of healthy women and women with BV. Nevertheless, real-time PCR has been more sensitive in diagnosis of bacterial vaginosis. DNA quantification of bacteria demonstrated that mutual abundance of G.vaginalis and A. vaginae was good bacterial vaginosis marker . On the contrary, Lactobacillus spp. was present in high amount in both healthy and bacterial vaginosis samples, but ratio of investigated bacteria was different between them. In fact, G. vaginalis and A. vaginae comprised only 0.1% of total microbiome in healthy, whereas Lactobacillus spp. took 99.3% of it. Nonetheless, in bacterial vaginosis, G. vaginalis and A. vaginae made up 34.4% of total microbiome, while Lactobacillus spp. was 21.6%.
 Conclusions: According to the results of our study real-time PCR analysis was more sensitive in diagnosis of bacterial vaginosis than Amsel’s method, as well as it represented fine tool in making a difference between microbial entities in healthy and bacterial vaginosis samples.

Association of key species of vaginal bacteria of recurrent bacterial vaginosis patients before and after oral metronidazole therapy with short- and long-term clinical outcomes

“…Others have reported that the relative abundance of pretreatment Lactobacillus, or the ratio of Gardnerella to Lactobacillus 16S DNA [67,103] or RNA [104], was associated with clinical outcome. Neither of these associations were significant in our cohort, nor in our larger cohort analyzed by qPCR [15]; abundance of total Lactobacillus spp or L. iners at pretreatment or among Amsel-negative posttreatment patients was not prognostic of clinical outcome.…”

Impact of cervicovaginal microbiome on the risk of cervical abnormalities development

“…Our result is controversial since different authors have linked a potential impact of GV in the development of cervical lesions and/or cancer while others fail to show any association 68,71–73 . Furthermore, some authors have been showing that quantification of some microorganisms such as GV may be of potential interest, which should be further explored 74 …”

“…68,[71][72][73] Furthermore, some authors have been showing that quantification of some microorganisms such as GV may be of potential interest, which should be further explored. 74 Regarding other common agents, we found that MH (p = 0.028; RR = 1.51) and Mob were highly associated with HPV-9val (p = 0.025; RR = 1.85). Nevertheless, Mob showed to be associated with protection against the development of any cervical lesion (p = 0.022; OR = 0.29).…”