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Frontiers in Cellular and Infection... 2021The vaginal microbiome is a well-defined compartment of the human microbiome. It has unique conditions, characterized by the dominance of one bacterial species, the... (Review)
Review
The vaginal microbiome is a well-defined compartment of the human microbiome. It has unique conditions, characterized by the dominance of one bacterial species, the This microbiota manifests itself by a low degree of diversity and by a strong dynamic of change in its composition under the influence of various exogenous and endogenous factors. The increase in diversity may paradoxically be associated with dysbiosis, such as bacterial vaginosis (BV). BV is the result of a disturbance in the vaginal ecosystem; i.e., a sudden replacement of by anaerobic bacteria such as , and others. It is the most common cause of vaginal discharge in women of childbearing age, approximately 30% of all causes. The etiology of this dysbiosis remains unknown, but its health consequences are significant, including obstetrical complications, increased risk of sexually transmitted infections and urogenital infections. Its diagnosis is based on Amsel's clinical criteria and/or a gram stain based on the Nugent score. While both of these methods have been widely applied worldwide for approximately three decades, Nugent score are still considered the "gold standard" of BV diagnostic tools. Given the limitations of these tools, methods based on molecular biology have been developed as alternative rational strategies for the diagnosis of BV. The treatment of BV aims at restoring the balance of the vaginal flora to stop the proliferation of harmful microorganisms. Prescription of antibiotics such as metronidazole, clindamycin, etc. is recommended. Faced with the considerable uncertainty about the cause of BV, the high rate of recurrence, the unacceptable treatment options, and clinical management which is often insensitive and inconsistent, research on this topic is intensifying. Knowledge of its composition and its associated variations represents the key element in improving the therapeutic management of patients with the most suitable treatments possible.
Topics: Ecosystem; Female; Gardnerella vaginalis; Humans; Lactobacillus; Vagina; Vaginosis, Bacterial
PubMed: 35118003
DOI: 10.3389/fcimb.2021.672429 -
American Journal of Obstetrics and... Mar 2021Bacterial vaginosis, pelvic inflammatory disease, and endometritis are infections of the genital tract that can lead to many adverse health outcomes, including... (Review)
Review
Bacterial vaginosis, pelvic inflammatory disease, and endometritis are infections of the genital tract that can lead to many adverse health outcomes, including infertility. Bacterial vaginosis is characterized by a lower prevalence of lactobacilli and a higher prevalence of anaerobic bacteria, including Gardnerella vaginalis, Megasphaera spp., and Atopobium vaginae. Endometritis and pelvic inflammatory disease are caused by the ascension of pathogenic bacteria to the uterus, although the mechanisms by which they do so are unclear. Bacterial vaginosis, chronic endometritis, and pelvic inflammatory disease have been linked to infertility in retrospective and prospective trials. Similarly, the causes of bacterial vaginosis and endometritis-related infertility are likely multifactorial and stem from inflammation, immune targeting of sperm antigens, the presence of bacterial toxins, and increased risk of sexually transmitted infections. Diagnosis and treatment of bacterial vaginosis, chronic endometritis, and pelvic inflammatory disease before attempting conception may be important components of preconceptional care for symptomatic women to improve outcomes of natural and assisted reproduction.
Topics: Endometritis; Female; Humans; Infertility, Female; Pelvic Inflammatory Disease; Vaginosis, Bacterial
PubMed: 33091407
DOI: 10.1016/j.ajog.2020.10.019 -
Advances in Experimental Medicine and... 2016The knowledge about the normal and abnormal vaginal microbiome has changed over the last years. Culturing techniques are not suitable any more for determination of a... (Review)
Review
The knowledge about the normal and abnormal vaginal microbiome has changed over the last years. Culturing techniques are not suitable any more for determination of a normal or abnormal vaginal microbiota. Non culture-based modern technologies revealed a complex and dynamic system mainly dominated by lactobacilli.The normal and the abnormal vaginal microbiota are complex ecosystems of more than 200 bacterial species influenced by genes, ethnic background and environmental and behavioral factors. Several species of lactobacilli per individuum dominate the healthy vagina. They support a defense system together with antibacterial substances, cytokines, defensins and others against dysbiosis, infections and care for an normal pregnancy without preterm birth.The numbers of Lactobacillus (L.) iners increase in the case of dysbiosis.Bacterial vaginosis (BV) - associated bacteria (BVAB), Atopobium vaginae and Clostridiales and one or two of four Gardnerella vaginalis - strains develop in different mixtures and numbers polymicrobial biofilms on the vaginal epithelium, which are not dissolved by antibiotic therapies according to guidelines and, thus, provoke recurrences.Aerobic vaginitis seems to be an immunological disorder of the vagina with influence on the microbiota, which is here dominated by aerobic bacteria (Streptococcus agalactiae, Escherichia coli). Their role in AV is unknown.Vaginal or oral application of lactobacilli is obviously able to improve therapeutic results of BV and dysbiosis.
Topics: Biofilms; Clostridiales; Dysbiosis; Escherichia coli; Female; Gardnerella vaginalis; Humans; Lactobacillus; Microbiota; Pregnancy; Premature Birth; Probiotics; Streptococcus agalactiae; Vagina; Vaginosis, Bacterial
PubMed: 27161352
DOI: 10.1007/978-3-319-31248-4_6 -
Current Opinion in Infectious Diseases Feb 2020The cause of bacterial vaginosis, the most common cause of vaginal discharge in women, remains controversial. We recently published an updated conceptual model on... (Review)
Review
PURPOSE OF REVIEW
The cause of bacterial vaginosis, the most common cause of vaginal discharge in women, remains controversial. We recently published an updated conceptual model on bacterial vaginosis pathogenesis, focusing on the roles of Gardnerella vaginalis and Prevotella bivia as early colonizers and Atopobium vaginae and other bacterial vaginosis-associated bacteria (BVAB) as secondary colonizers in this infection. In this article, we extend the description of our model to include a discussion on the role of host-vaginal microbiota interactions in bacterial vaginosis pathogenesis.
RECENT FINDINGS
Although G. vaginalis and P. bivia are highly abundant in women with bacterial vaginosis, neither induce a robust inflammatory response from vaginal epithelial cells. These early colonizers may be evading the immune system while establishing the bacterial vaginosis biofilm. Secondary colonizers, including A. vaginae, Sneathia spp., and potentially other BVAB are more potent stimulators of the host-immune response to bacterial vaginosis and likely contribute to its signs and symptoms as well as its adverse outcomes.
SUMMARY
Elucidating the cause of bacterial vaginosis has important implications for diagnosis and treatment. Our current bacterial vaginosis pathogenesis model provides a framework for key elements that should be considered when designing and testing novel bacterial vaginosis diagnostics and therapeutics.
Topics: Bacteria; Biofilms; Female; Host-Pathogen Interactions; Humans; Microbiota; Vagina; Vaginosis, Bacterial
PubMed: 31789672
DOI: 10.1097/QCO.0000000000000620 -
The Journal of Infectious Diseases Aug 2021Pelvic inflammatory disease (PID) is a clinical syndrome that has been associated with a wide range of potential causal pathogens. Three broad groups of organisms have...
Pelvic inflammatory disease (PID) is a clinical syndrome that has been associated with a wide range of potential causal pathogens. Three broad groups of organisms have been isolated from the genital tract of people with PID: sexually transmitted organisms such as Neisseria gonorrhoeae, Chlamydia trachomatis, Mycoplasma genitalium, and Trichomonas vaginalis; bacterial vaginosis (BV)-associated species and genera such as Atopobium vaginae, Sneathia, and Megasphaera; and genera and species usually associated with the gastrointestinal or respiratory tracts such as Bacteroides, Escherichia coli, Streptococcus, or Haemophilus influenza. Although PID is often considered to be synonymous with gonorrhea or chlamydia, these pathogens are found in only one quarter to one third of people with PID, suggesting that broader screening and diagnostic and treatment strategies need to be considered to reduce the burden of PID and its associated sequelae.
Topics: Chlamydia Infections; Chlamydia trachomatis; Female; Gonorrhea; Humans; Mycoplasma Infections; Mycoplasma genitalium; Neisseria gonorrhoeae; Pelvic Inflammatory Disease; Sexually Transmitted Diseases; Vagina
PubMed: 34396407
DOI: 10.1093/infdis/jiab067 -
Genome Medicine Nov 2016Endometrial cancer studies have led to a number of well-defined but mechanistically unconnected genetic and environmental risk factors. One of the emerging modulators...
BACKGROUND
Endometrial cancer studies have led to a number of well-defined but mechanistically unconnected genetic and environmental risk factors. One of the emerging modulators between environmental triggers and genetic expression is the microbiome. We set out to inquire about the composition of the uterine microbiome and its putative role in endometrial cancer.
METHODS
We undertook a study of the microbiome in samples taken from different locations along the female reproductive tract in patients with endometrial cancer (n = 17), patients with endometrial hyperplasia (endometrial cancer precursor, n = 4), and patients afflicted with benign uterine conditions (n = 10). Vaginal, cervical, Fallopian, ovarian, peritoneal, and urine samples were collected aseptically both in the operating room and the pathology laboratory. DNA extraction was followed by amplification and high-throughput next generation sequencing (MiSeq) of the 16S rDNA V3-V5 region to identify the microbiota present. Microbiota data were summarized using both α-diversity to reflect species richness and evenness within bacterial populations and β-diversity to reflect the shared diversity between bacterial populations. Statistical significance was determined through the use of multiple testing, including the generalized mixed-effects model.
RESULTS
The microbiome sequencing (16S rDNA V3-V5 region) revealed that the microbiomes of all organs (vagina, cervix, Fallopian tubes, and ovaries) are significantly correlated (p < 0.001) and that there is a structural microbiome shift in the cancer and hyperplasia cases, distinguishable from the benign cases (p = 0.01). Several taxa were found to be significantly enriched in samples belonging to the endometrial cancer cohort: Firmicutes (Anaerostipes, ph2, Dialister, Peptoniphilus, 1-68, Ruminococcus, and Anaerotruncus), Spirochaetes (Treponema), Actinobacteria (Atopobium), Bacteroidetes (Bacteroides and Porphyromonas), and Proteobacteria (Arthrospira). Of particular relevance, the simultaneous presence of Atopobium vaginae and an uncultured representative of the Porphyromonas sp. (99 % match to P. somerae) were found to be associated with disease status, especially if combined with a high vaginal pH (>4.5).
CONCLUSIONS
Our results suggest that the detection of A. vaginae and the identified Porphyromonas sp. in the gynecologic tract combined with a high vaginal pH is statistically associated with the presence of endometrial cancer. Given the documented association of the identified microorganisms with other pathologies, these findings raise the possibility of a microbiome role in the manifestation, etiology, or progression of endometrial cancer that should be further investigated.
Topics: Adult; Aged; Bacteria; DNA, Bacterial; DNA, Ribosomal; Endometrial Hyperplasia; Endometrial Neoplasms; Fallopian Tubes; Female; Humans; Middle Aged; Ovary; Phylogeny; RNA, Ribosomal, 16S; Risk Factors; Sequence Analysis, DNA; Urine; Uterus; Vagina
PubMed: 27884207
DOI: 10.1186/s13073-016-0368-y -
F1000Research 2017Bacterial vaginosis is the most prevalent cause of abnormal vaginal discharge in women of childbearing age. It can have a major impact on quality of life and... (Review)
Review
Bacterial vaginosis is the most prevalent cause of abnormal vaginal discharge in women of childbearing age. It can have a major impact on quality of life and psychological wellbeing if frequently recurrent and strongly symptomatic. The use of molecular techniques to study the vaginal microbiome is increasing our understanding of the dynamic changes in flora that occur in health and disease. It might soon be possible to separate into different pathogenic and non-pathogenic species. Many groups are studying compounds that can disrupt the biofilm which is dominated by and . Several studies in the last decade support the concept of bacterial vaginosis as a sexually transmitted infection.
PubMed: 29043070
DOI: 10.12688/f1000research.11417.1 -
Journal of Infection in Developing... Sep 2021The 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...
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.
Topics: Actinobacteria; Adult; Case-Control Studies; Female; Gardnerella vaginalis; Gram-Positive Bacterial Infections; Humans; Lactobacillus; Real-Time Polymerase Chain Reaction; Serbia; Vaginosis, Bacterial; Young Adult
PubMed: 34669599
DOI: 10.3855/jidc.13091 -
Beneficial Microbes Feb 2019Bacterial vaginosis (BV) is the most common cause of vaginal discomfort in women. It is characterised by abnormal vaginal microbiota with a depletion of lactobacilli and... (Randomized Controlled Trial)
Randomized Controlled Trial
Evidence-based mixture containing Lactobacillus strains and lactoferrin to prevent recurrent bacterial vaginosis: a double blind, placebo controlled, randomised clinical trial.
Bacterial vaginosis (BV) is the most common cause of vaginal discomfort in women. It is characterised by abnormal vaginal microbiota with a depletion of lactobacilli and predominance of anaerobic microorganisms, mainly Gardnerella vaginalis and Atopobium vaginae. Although antibiotics represent an effective therapeutic option in the short-term, recurrent infections still remain a serious problem. Nowadays, evidence exists about the efficacy of probiotics for the management of BV. The aim of the current double blind, randomised clinical trial was to assess the efficacy of a probiotic mixture, including Lactobacillus acidophilus GLA-14 and Lactobacillus rhamnosus HN001, in combination with bovine lactoferrin, as adjuvant therapy to metronidazole in women with recurrent BV. In particular, normalisation of Nugent score, remission of symptoms and recurrences during a six-months follow-up were assessed. 48 adult women received metronidazole (500 mg twice daily) for 7 days and randomly assigned to take simultaneously either probiotics plus lactoferrin or placebo (2 capsules/day for 5 days followed by 1 capsule/day for 10 consecutive days; induction phase). The verum or placebo administration (1 capsule/day for 10 consecutive days) was repeated each month (maintenance phase) during the six months of follow-up starting the first day of menstrual cycle since the menstrual blood increases the vaginal pH and contributes to increase the risk of recurrences. The results showed that symptoms (vaginal discharge and itching), Nugent score and recurrence rate were significantly improved by probiotics mixture in association with lactoferrin. This alternative approach may represent a safe and effective remedy for the restoration of healthy vaginal microbiota in preventing recurrent BV.
Topics: Adolescent; Adult; Combined Modality Therapy; Double-Blind Method; Female; Humans; Lactobacillus; Lactoferrin; Metronidazole; Middle Aged; Probiotics; Prospective Studies; Recurrence; Secondary Prevention; Treatment Outcome; Vaginosis, Bacterial; Young Adult
PubMed: 30525953
DOI: 10.3920/BM2018.0075 -
Pathogens (Basel, Switzerland) Feb 2021Bacterial vaginosis (BV) is associated with a highly structured polymicrobial biofilm on the vaginal epithelium where species presumably play a pivotal role. , , and...
Bacterial vaginosis (BV) is associated with a highly structured polymicrobial biofilm on the vaginal epithelium where species presumably play a pivotal role. , , and are vaginal pathogens detected during the early stages of incident BV. Herein, we aimed to analyze the impact of and on a pre-established biofilm using a novel in vitro triple-species biofilm model. Total biofilm biomass was determined by the crystal violet method. We also discriminated the bacterial populations in the biofilm and in its planktonic fraction by using PNA FISH. We further analyzed the influence of and on the expression of key virulence genes of by quantitative PCR. In our tested conditions, and were able to incorporate into pre-established biofilms but did not induce an increase in total biofilm biomass, when compared with 48-h biofilms. However, they were able to significantly influence the expression of , a gene suggested to be associated with biofilm maintenance in . This study suggests that microbial relationships between co-infecting bacteria can deeply affect the biofilm, a crucial marker of BV.
PubMed: 33672647
DOI: 10.3390/pathogens10020247