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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 -
Frontiers in Cellular and Infection... 2021The vaginal microbiome plays a critical role in determining the progression of female genital tract infections; however, little is known about the vaginal microbiota of...
The vaginal microbiome plays a critical role in determining the progression of female genital tract infections; however, little is known about the vaginal microbiota of Indian women. We aimed to investigate the vaginal microbial architecture of women with asymptomatic bacterial vaginosis (BV) (n=20) and normal microbiota (n=19). Microbial diversity was analyzed in vaginal swabs from regularly menstruating women (18-45yrs) by 16S rRNA V3-V4 amplicon (MiSeq Illumina) sequencing. Rarefaction analysis showed a higher number of species in normal flora compared to BV. Alpha diversity as measured by Pielou's evenness revealed microbial diversity was significantly greater in BV samples than normal microbiota (p= 0.0165). Beta diversity comparison using UniFrac metrics indicated distinct microbial communities clustering between normal and BV flora. Firmicutes were the major phyla observed in vaginal specimens of normal microbiota whereas were significantly abundant in BV samples. Notably, the relative abundance of was significantly high in normal microbiota. Conversely , , , , , significantly dominated dysbiotic microbiota. Relative frequency of Lactobacillus decreased significantly in BV (6%) as compared to normal microbiota (35.2%). , more exclusively present in normal microbiota. was detected from both the groups with a relative frequency of 50.4% and 17.2% in normal and BV microbiota respectively. Lefse analysis indicated in the vaginal microbiota as a biomarker for dysbiosis and as a biomarker of a healthy microbiota were negatively correlated to , and . Proteobacteria positively correlated to s, and were shown to be positively correlated to Predicted functional analysis indicated differences in the functional profiles between BV and normal microbiota. Normal microbiota utilized pathways essential for phosphatidylglycerol biosynthesis I & II, peptidoglycan biosynthesis, geranylgeranyl diphosphate biosynthesis I, mevalonate pathway, CoA biosynthesis pathway I and pyrimidine nucleotide salvage; whereas BV bacteria had characteristic aromatic amino acid biosynthesis, pentose phosphate pathway, carbohydrate degradation. In conclusion, women with asymptomatic BV have vaginal microbiota significantly different than women with normal microbiota. Furthermore, the study provides insights into the vaginal microbial structure of Indian women that will enable us to explore the prospective candidates for restoring the vaginal microbiota.
Topics: Dysbiosis; Female; Humans; Microbiota; Prospective Studies; RNA, Ribosomal, 16S; Vagina
PubMed: 35096634
DOI: 10.3389/fcimb.2021.760459 -
Frontiers in Cellular and Infection... 2021Bacterial Vaginosis (BV) involves the presence of a multi-species biofilm adhered to vaginal epithelial cells, but its in-depth study has been limited due to the...
Bacterial Vaginosis (BV) involves the presence of a multi-species biofilm adhered to vaginal epithelial cells, but its in-depth study has been limited due to the complexity of the bacterial community, which makes the design of models challenging. Perhaps the most common experimental technique to quantify biofilms is the crystal violet (CV) staining method. Despite its widespread utilization, the CV method is not without flaws. While biofilm CV quantification within the same strain in different conditions is normally accepted, assessing multi-species biofilms formation by CV staining might provide significant bias. For BV research, determining possible synergism or antagonism between species is a fundamental step for assessing the roles of individual species in BV development. Herein, we provide our perspective on how CV fails to properly quantify an triple-species biofilm composed of , , and , three common BV-associated bacteria thought to play key roles in incident BV pathogenesis. We compared the CV method with total colony forming units (CFU) and fluorescence microscopy cell count methods. Not surprisingly, when comparing single-species biofilms, the relationship between biofilm biomass, total number of cells, and total cultivable cells was very different between each tested method, and also varied with the time of incubation. Thus, despite its wide utilization for single-species biofilm quantification, the CV method should not be considered for accurate quantification of multi-species biofilms in BV pathogenesis research.
Topics: Bacteria; Biofilms; Female; Gentian Violet; Humans; Staining and Labeling; Vagina; Vaginosis, Bacterial
PubMed: 35071046
DOI: 10.3389/fcimb.2021.795797 -
Bioengineered Feb 2022To explore a new marker which can detect bacterial vaginosis (BV) with high sensitivity and specificity quantitatively. According to the Nugent Score, vaginal secretions...
To explore a new marker which can detect bacterial vaginosis (BV) with high sensitivity and specificity quantitatively. According to the Nugent Score, vaginal secretions from study participants were divided into BV, healthy, and BV-intermediate groups. First, we compared the obvious differences and high abundance of bacteria in the three groups using 16S rRNA-sequencing, and screened out candidate markers. Then, quantitative detection of these candidate markers from the three groups was done using real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR), followed by evaluation of the sensitivity and specificity. Finally, we verified the new markers using clinical cases. were screened out by 16S rRNA-sequencing. RT-qPCR data were transformed and analyzed through ROC curves. PCR results for these bacteria were log-transformed using as the numerator and other BV-related bacteria as the denominator. Four new indicators were found. Of these, log / (L/G) <0 was the best indicator. The sensitivity, specificity, positive predictive value, and negative predictive value of our system were 93.5%, 97.2%, 96.6 and 94.6%, respectively. Combination of data for 16S rRNA-sequencing and RT-qPCR revealed four indicators for BV detection. Of these, log L/G < 0 was the best indicator. Creating a molecular-diagnostic system independent of the Nugent Score for BV could have an important impact on the clinical management of BV.: log / (logL/G); Bacterial vaginosis (BV); vaginal secretions (VSs); polymerase chain reaction (PCR); rRNA-sequencing (rRNA-seq); real-time reverse transcription-quantitative polymerase chain reaction (RT-qPCR); operational taxonomic unit (OTU); non-metric multidimensional scaling (NMDS); receiver operating characteristic (ROC).
Topics: Adolescent; Adult; China; Cohort Studies; Diagnostic Techniques, Obstetrical and Gynecological; Female; Gardnerella vaginalis; Humans; Lactobacillus crispatus; Middle Aged; RNA, Bacterial; RNA, Ribosomal, 16S; RNA-Seq; Real-Time Polymerase Chain Reaction; Reproducibility of Results; Sensitivity and Specificity; Sequence Analysis, RNA; Vaginosis, Bacterial; Young Adult
PubMed: 35038957
DOI: 10.1080/21655979.2022.2027059 -
NPJ Biofilms and Microbiomes Dec 2021Bacterial vaginosis (BV) is an enigmatic polymicrobial condition characterized by a depletion of health-associated Lactobacillus and an overgrowth of anaerobes....
Bacterial vaginosis (BV) is an enigmatic polymicrobial condition characterized by a depletion of health-associated Lactobacillus and an overgrowth of anaerobes. Importantly, BV is linked to adverse gynecologic and obstetric outcomes: an increased risk of sexually transmitted infections, preterm birth, and cancer. We hypothesized that members of the cervicovaginal microbiota distinctly contribute to immunometabolic changes in the human cervix, leading to these sequelae. Our 3D epithelial cell model that recapitulates the human cervical epithelium was infected with clinical isolates of cervicovaginal bacteria, alone or as a polymicrobial community. We used Lactobacillus crispatus as a representative health-associated commensal and four common BV-associated species: Gardnerella vaginalis, Prevotella bivia, Atopobium vaginae, and Sneathia amnii. The immunometabolic profiles of these microenvironments were analyzed using multiplex immunoassays and untargeted global metabolomics. A. vaginae and S. amnii exhibited the highest proinflammatory potential through induction of cytokines, iNOS, and oxidative stress-associated compounds. G. vaginalis, P. bivia, and S. amnii distinctly altered physicochemical barrier-related proteins and metabolites (mucins, sialic acid, polyamines), whereas L. crispatus produced an antimicrobial compound, phenyllactic acid. Alterations to the immunometabolic landscape correlate with symptoms and hallmarks of BV and connected BV with adverse women's health outcomes. Overall, this study demonstrated that 3D cervical epithelial cell colonized with cervicovaginal microbiota faithfully reproduce the immunometabolic microenvironment previously observed in clinical studies and can successfully be used as a robust tool to evaluate host responses to commensal and pathogenic bacteria in the female reproductive tract.
Topics: Bacteria; Cervix Uteri; Female; Gardnerella vaginalis; Humans; Infant, Newborn; Premature Birth; Vaginosis, Bacterial
PubMed: 34903740
DOI: 10.1038/s41522-021-00259-8 -
Frontiers in Cellular and Infection... 2021Bacterial vaginosis (BV) is the most common vaginal infection in women of reproductive age and has been associated with serious health complications, mainly in pregnant...
Bacterial vaginosis (BV) is the most common vaginal infection in women of reproductive age and has been associated with serious health complications, mainly in pregnant women. It is characterized by a decrease in the number of species in the healthy vaginal microbiota and an overgrowth of strict and facultative anaerobic bacteria that develop a polymicrobial biofilm. Despite over 60 years of research investigating BV, its etiology is not fully understood. spp. is a crucial microorganism that contributes to the formation of the biofilm and the development of BV, but the role of other BV-associated bacteria is not clear. Nevertheless, (previously known as ) is a highly specific species for BV, and co-colonization with is thought to be a very specific diagnostic marker. The diagnosis of BV still presents some limitations, since currently used methods often fail to accurately detect BV. This work aims to develop a novel peptide nucleic acid (PNA) probe targeting . This probe was further validated in a multiplex assay, which included a specific PNA probe, as a possible method for diagnosis of BV, and was compared with quantification by qPCR. The new PNA probe showed excellent sensitivity and specificity and could discriminate - biofilms, confirming the potential to be used for the detection of BV-associated pathogens.
Topics: Actinobacteria; Female; Gardnerella vaginalis; Humans; Pregnancy; Vagina; Vaginosis, Bacterial
PubMed: 34869078
DOI: 10.3389/fcimb.2021.779376 -
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 -
Frontiers in Immunology 2021The standard treatment for bacterial vaginosis (BV) with oral metronidazole is often ineffective, and recurrence rates are high among African women. BV-associated...
The standard treatment for bacterial vaginosis (BV) with oral metronidazole is often ineffective, and recurrence rates are high among African women. BV-associated anaerobes are closely associated with genital inflammation and HIV risk, which underscores the importance of understanding the interplay between vaginal microbiota and genital inflammation in response to treatment. In this cohort study, we therefore the effects of metronidazole treatment on the vaginal microbiota and genital cytokines among symptomatic South African women with BV [defined as Nugent score (NS) ≥4] using 16S rRNA gene sequencing and multiplex bead arrays. Among 56 BV-positive women, we observed short-term BV clearance (NS <4) in a proportion of women six weeks after metronidazole treatment, with more than half of these experiencing recurrence by 12 weeks post-treatment. BV treatment temporarily reduced the relative abundance of BV-associated anaerobes (particularlyand) and increased lactobacilli species (mainly ), resulting in significantly altered mucosal immune milieu over time. In a linear mixed model, the median concentrations of pro-inflammatory cytokines and chemokines were significantly reduced in women who cleared BV compared to pre-treatment. BV persistence and recurrence were strongly associated with mucosal cytokine profiles that may increase the risk of HIV acquisition. Concentrations of these cytokines were differentially regulated by changes in the relative abundance of BVAB1 and. We conclude that metronidazole for the treatment of BV induced short-term shifts in the vaginal microbiota and mucosal cytokines, while treatment failures promoted persistent elevation of pro-inflammatory cytokine concentrations in the genital tract. These data suggest the need to improve clinical management of BV to minimize BV related reproductive risk factors.
Topics: Administration, Oral; Adult; Anti-Bacterial Agents; Bacteria; Cytokines; Dysbiosis; Female; Host-Pathogen Interactions; Humans; Inflammation Mediators; Longitudinal Studies; Metronidazole; Mucous Membrane; Prospective Studies; Reinfection; South Africa; Time Factors; Treatment Outcome; Vagina; Vaginosis, Bacterial; Young Adult
PubMed: 34594336
DOI: 10.3389/fimmu.2021.730986 -
Open Forum Infectious Diseases Sep 2021The cervicovaginal microbiota, including sexually transmitted infections (STIs), have not been well described in female genital schistosomiasis (FGS).
BACKGROUND
The cervicovaginal microbiota, including sexually transmitted infections (STIs), have not been well described in female genital schistosomiasis (FGS).
METHODS
Women (aged 18-31, sexually active, nonpregnant) were invited to participate at the final follow-up of the HPTN 071 (PopART) Population Cohort in January-August 2018. We measured key species of the cervicovaginal microbiota (, , , , and ) and STIs (, , , and ) using quantitative PCR (qPCR). We evaluated associations of the microbiota and STI presence and concentration with FGS (qPCR-detected DNA in any of 3 genital specimens).
RESULTS
The presence and concentration of key cervicovaginal species did not differ between participants with (n = 30) or without FGS (n = 158). A higher proportion of participants with FGS had compared with FGS-negative women ( = .08), with further analysis showing that was more prevalent among women with ≥2 qPCR-positive genital specimens (50.0%, 8/16) than among FGS-negative women (21.5%, 34/158; = .01).
CONCLUSIONS
We found weak evidence of an association between the presence of and FGS, with a stronger association in women with a higher-burden FGS infection. Additional research is needed on potential between-parasite interactions, especially regarding HIV-1 vulnerability.
PubMed: 34557562
DOI: 10.1093/ofid/ofab438 -
Anaerobe Dec 2021Gardnerella vaginalis in association with anaerobes has been linked to bacterial vaginosis in women, while urinary tract infections (UTIs) in men have rarely been... (Review)
Review
Gardnerella vaginalis in association with anaerobes has been linked to bacterial vaginosis in women, while urinary tract infections (UTIs) in men have rarely been reported. The aim of the review was to reveal the significance of G. vaginalis UTIs in men. Prevalence of G. vaginalis UTIs in men varied from 0.5 to >27% according to patients' groups. Most patients had comorbidity such as urolithiasis or stents, transplants, tumors and diabetes, however, infections can also affect immunocompetent patients. We observed G. vaginalis-associated bacteriuria and leukocyturia in a kidney transplant man. Complications of the UTIs such as bacteremia (in 9/11 cases), hydronephrosis (4/11) and abscesses or septic emboli have been reported. Bacterial vaginosis in female partners has been a risk factor for UTIs in males. In women, biofilm Gardnerella phenotype, stabilized by Atopobium vaginae and Prevotella bivia was linked to ≥6-fold higher antibiotic resistance rates compared with the planktonic phenotype. Non-susceptibility to metronidazole and levofloxacin was found also in males. Therefore, if aerobic urine cultures are negative, urine and blood samples from male patients with predisposing factors and clinical signs of UTIs and bacteremia, can be taken. Plates should be incubated for 2-4 days in capnophilic/microaerophilic conditions, however only anaerobic incubation can help with detecting G. vaginalis strains which grow only anaerobically. Susceptibility testing of the isolates is highly important. Briefly, adherent G. vaginalis phenotype can be sexually transmissible. Despite the infrequency of G. vaginalis UTIs in men, the infections should be considered since they are often linked to severe complications.
Topics: Disease Management; Disease Susceptibility; Female; Gardnerella vaginalis; Gram-Positive Bacterial Infections; Humans; Male; Prevalence; Risk Factors; Sex Factors; Sexually Transmitted Diseases, Bacterial; Urinary Tract Infections; Vaginosis, Bacterial
PubMed: 34530110
DOI: 10.1016/j.anaerobe.2021.102438