High Atopobium vaginae and Gardnerella vaginalis vaginal loads are associated with preterm birth

Urinary symptoms are associated with certain urinary microbes in urogynecologic surgical patients

INTRODUCTION AND HYPOTHESIS

Persistent and de novo symptoms decrease satisfaction after urogynecologic surgery. We investigated whether the preoperative bladder microbiome is associated with urinary symptoms prior to and after urogynecologic surgery.

METHODS

One hundred twenty-six participants contributed responses to the validated OABq symptom questionnaire. Catheterized (bladder) urine samples and vaginal and perineal swabs were collected immediately preoperatively. Bacterial DNA in the urine samples and swabs was sequenced and classified.

RESULTS

Preoperative symptom severity was significantly worse in sequence-positive patients. Higher OABq Symptom Severity (OABqSS) scores (more symptomatic) were associated with higher abundance in bladder urine of two bacterial species: Atopobium vaginae and Finegoldia magna. The presence of Atopobium vaginae in bladder urine also was correlated with its presence in either the vagina or perineum.

CONCLUSIONS

Two specific bacterial species detected in bladder urine, Atopobium vaginae and Finegoldia magna, are associated with preoperative urinary symptom severity in women undergoing POP/SUI surgery. The reservoir for Atopobium vaginae may be adjacent pelvic floor niches. This observation should be validated in a larger cohort to determine whether there is a microbiologic etiology for certain preoperative urinary symptoms.

Inhibition of sialidase activity and cellular invasion by the bacterial vaginosis pathogen Gardnerella vaginalis

Bacterial vaginosis is a genital tract infection, thought to be caused by transformation of a lactobacillus-rich flora to a dysbiotic microbiota enriched in mixed anaerobes. The most prominent of these is Gardnerella vaginalis (GV), an anaerobic pathogen that produces sialidase enzyme to cleave terminal sialic acid residues from human glycans. Notably, high sialidase activity is associated with preterm birth and low birthweight. We explored the potential of the sialidase inhibitor Zanamavir against GV whole cell sialidase activity using methyl–umbelliferyl neuraminic acid (MU-NANA) cleavage assays, with Zanamavir causing a 30% reduction in whole cell GV sialidase activity (p < 0.05). Furthermore, cellular invasion assays using HeLa cervical epithelial cells, infected with GV, demonstrated that Zanamivir elicited a 50% reduction in cell association and invasion (p < 0.05). Our data thus highlight that pharmacological sialidase inhibitors are able to modify BV-associated sialidase activity and influence host–pathogen interactions and may represent novel therapeutic adjuncts.

Unraveling Gardnerella vaginalis Surface Proteins Using Cell Shaving Proteomics

Gardnerella vaginalis is one of the main etiologic agents of bacterial vaginosis (BV). This infection is responsible for a wide range of public health costs and is associated with several adverse outcomes during pregnancy. Improving our understanding of G. vaginalis protein cell surface will assist in BV diagnosis. This study represents the first proteomic approach that has analyzed the exposed proteins on G. vaginalis cell surface using a shaving approach. The 261 G. vaginalis proteins identified using this approach were analyzed with bioinformatic tools to detect characteristic motifs from surface-exposed proteins, such as signal peptides (36 proteins), lipobox domains (17 proteins), LPXTG motifs (5 proteins) and transmembrane alpha-helices (66 proteins). One third of the identified proteins were found to have at least one typical motif of surface-exposed proteins. Furthermore, the subcellular location was examined using two predictors (PSORT and Gpos-mPLoc). These bioinformatic tools classified 17% of the identified proteins as surface-associated proteins. Interestingly, we identified 13 members of the ATP-binding cassette (ABC) superfamily, which were mainly involved in the translocation of various substrates across membranes. To validate the location of the G. vaginalis surface-exposed proteins, an immunofluorescence assay with antibodies against Escherichia coli GroEL was performed to reveal the extracellular location of the moonlighting GroEL. In addition, monoclonal antibodies (mAb) against G. vaginalis Cna protein were produced and used to validate the location of Cna on the surface of the G. vaginalis. These high affinity anti-Cna mAb represent a useful tool for the study of this pathogenic microorganism and the BV.

Characterization of a novel Gram-stain-positive anaerobic coccus isolated from the female genital tract: Genome sequence and description of Murdochiella vaginalis sp. nov

Strain Marseille-P2341^T , a nonmotile, nonspore-forming, Gram-stain-positive anaerobic coccus, was isolated in the vaginal specimen of a patient with bacterial vaginosis using culturomics. Its growth occurred at temperatures ranging from 25 to 42°C, with pH between 6.5 and 8.5, and at NaCl concentrations lower than 5%. The major fatty acids were C_18:1n9 (27.7%) and C_16:0 (24.4%). Its genome is 1,671,491 bp long with 49.48 mol% of G+C content. It is composed of 1,501 genes: 1,446 were protein-coding genes and 55 were RNAs. Strain Marseille-P2341^T shared 97.3% of 16S rRNA gene sequence similarity with Murdochiella asaccharolytica, the phylogenetically closest species. These results enabled the classification of strain Marseille-P2341^T as a new species of the genus Murdochiella for which we proposed the name Murdochiella vaginalis sp. nov. The type strain is strain Marseille-P2341^T (=DSM 102237, =CSUR P2341).

Bacterial identification of the vaginal microbiota in Ecuadorian pregnant teenagers: an exploratory analysis

Background

Bacterial vaginosis (BV) is a microbial imbalance (i.e., dysbiosis) that can produce serious medical effects in women at childbearing age. Little is known, however, about the incidence of BV or vaginal microbiota dysbiosis in pregnant teenagers in low and middle-income countries such as Ecuador. The scope of this exploratory analysis was to study the relationship between epidemiologic and microbial risk factors. Among the microbiology risk factors this study investigated five Lactobacillus species, two of them know in preview studies as microbiology risk factors for BV development (Lactobacillus acidophilus and Lactobacillus iners), and the last three known for being associated with a healthy vaginal tract (Lactobacillus crispatus, Lactobacillus gasseri and Lactobacillus jensenii). In addition, fastidious anaerobes known to be microbial risk factors for BV development in pregnant teenagers were searched as well, more exactly, Gardnerella vaginalis, Atopobium vaginae and Mobiluncus mulieris.

Methods

Ninety-five healthy adolescent pregnant women, visiting a secondary level hospital in Quito, Ecuador, were enrolled into the study in 2015. The enrolled patients were between 10 to 13 weeks of pregnancy. Four epidemiological risk factors were collected in a survey: age, civil status, sexual partners and condom use. Also, vaginal pH was measured as a health risk factor. DNA was extracted from endocervical and exocervical epithelia from all the patients’ samples. PCR analysis was performed in order to characterize the presence of the eight bacterial species known as risk factors for BV development, targeting three anaerobes and five Lactobacillus species. Univariate and multivariate analysis were performed to identify associated factors for the presence of anaerobic species using logistic regression.

Results

The 95 vaginal microflora samples of these teenagers were analyzed. Two of the bacterial species known to cause BV: A. vaginae (100%) and G. vaginalis (93.7%) were found in high prevalence. Moreover, the most predominant bacterial Lactobacillus species found in the pregnant teenagers’ vaginal tract were L. crispatus (92.6%), L. iners (89.5%) and L. acidophilus (87.4%). In addition, the average vaginal pH measured in the study population was 5.2, and high pH was associated with the presence of the three-anaerobic species (p = 0.001). Finally, L. jensenii’s presence in the study decreased in 72% the occupation of the three anaerobes.

Discussion

This work identified a high pH as a risk factor for BV anaerobes’ presence in adolescent pregnant women. Moreover, this study identified L. crispatus, L. iners and L. acidophilus to be the most abundant species in our study population. From all fastidious anaerobes analyzed in this study, A. vaginae was present in all pregnant teenagers. To conclude, L. jensenii could be a potential healthy vaginal microbiota candidate in pregnant teenagers and should be further analyzed in future studies.

Prevalence of bacterial vaginosis in Portuguese pregnant women and vaginal colonization by Gardnerella vaginalis

Background

We aimed to determine the prevalence of vaginal colonization by Gardnerella vaginalis and of bacterial vaginosis (BV) in Portuguese pregnant women, and to identify risk factors for BV and G. vaginalis colonization in pregnancy.

Methods

A cross-sectional study was conducted among pregnant women aged ≥ 18 years who were attending in two public hospitals of the Northwest region of Portugal. Epidemiological data was collected by anonymous questionnaire. BV was diagnosed by Nugent criteria and G. vaginalis presence was identified by polymerase chain reaction. Crude associations between the study variables and BV or G. vaginalis colonization were quantified by odds ratios (ORs) and their 95% confidence intervals (CIs).

Results

The prevalences of BV and of G. vaginalis colonization among Portuguese pregnant women were 3.88% and 67.48%, respectively. Previous preterm delivery and colonization by G. vaginalis were factors with very high OR, but only statistically significant for a 90% CI. Conversely, higher rates of G. vaginalis colonization were found in women with basic educational level (OR = 2.77, 95% CI [1.33–5.78]), during the second trimester of pregnancy (OR = 6.12, 95% CI [1.80–20.85]) and with BV flora (OR = 8.73, 95% CI [0.50–153.60]).

Discussion

Despite the lower number of women with BV, prevalence ratios and association with risk factors were similar to recent European studies. However, the percentage of healthy women colonized by G. vaginalis was significantly higher than many previous studies, confirming that G. vaginalis colonization does not always lead to BV development.

Vaginal self-sampling as a diagnosis tool in low-income countries and potential applications for exploring the infectious causes of miscarriage

Gynecological health is a challenge in low-income countries. Personal opposition to perineal examination has been overcome by the use of vaginal self-sampling. Here, we review the use of this procedure notably in low-income countries and the main infectious causes of miscarriage. Vaginal self-sampling was mainly used for human papillomavirus detection but also to detect microorganisms causing sexually transmitted infections or bacterial vaginosis. 58 studies have been performed in low-resource countries, mainly studies performed to detect human papillomavirus in urban and peri-urban areas and demonstrating excellent acceptability. Several infectious causes of miscarriage could be tested using self-vaginal samples. In the future, such strategies coupled with a rapid-identification point-of-care method could allow the development of screening and treatment programs in rural areas in low-resource countries.

Multiplex Peptide Nucleic Acid Fluorescence In Situ Hybridization (PNA-FISH) for Diagnosis of Bacterial Vaginosis

Fluorescence in situ hybridization (FISH) is a molecular method used to identify and quantify microorganisms in a wide range of samples. This technique combines the simplicity of microscopic observation and the specificity of DNA/rRNA hybridization, allowing detection of selected bacterial species and morphologic visualization. Here, we describe a quantitative molecular diagnosis of bacterial vaginosis, based on the classical Nugent score. Our probes are able to differentiate Lactobacillus spp. and Gardnerella vaginalis from the other undefined bacterial species considered in the Nugent score.

Taxonogenomics and description of Vaginella massiliensis gen. nov., sp. nov., strain Marseille P2517T, a new bacterial genus isolated from the human vagina

An obligate aerobic, Gram-negative, nonmotile and nonsporulating rod designated Marseille P2517 was isolated from the vaginal flora. We describe its features, annotate the genome and compare it to the closest species. The 16S rRNA analysis shows 93.03% sequence similarity with Weeksella virosa, the phylogenetically closest species. Its genome is 2 434 475 bp long and presents 38.16% G+C. On the basis of these data, it can be considered as a new genus in the Flavobacteriaceae family, for which we proposed the name Vaginella massiliensis gen. nov., sp. nov. The type strain is Marseille P2517T.

The Point-of-Care Laboratory in Clinical Microbiology

Point-of-care (POC) laboratories that deliver rapid diagnoses of infectious diseases were invented to balance the centralization of core laboratories. POC laboratories operate 24 h a day and 7 days a week to provide diagnoses within 2 h, largely based on immunochromatography and real-time PCR tests. In our experience, these tests are conveniently combined into syndrome-based kits that facilitate sampling, including self-sampling and test operations, as POC laboratories can be operated by trained operators who are not necessarily biologists. POC laboratories are a way of easily providing clinical microbiology testing for populations distant from laboratories in developing and developed countries and on ships. Modern Internet connections enable support from core laboratories. The cost-effectiveness of POC laboratories has been established for the rapid diagnosis of tuberculosis and sexually transmitted infections in both developed and developing countries.

[Bacterial vaginosis and spontaneous preterm birth]

OBJECTIVE

To determine if bacterial vaginosis is a marker for risk of spontaneous preterm delivery and if its detection and treatment can reduce this risk.

METHODS

Consultation of the database Pubmed/Medline, Science Direct, and international guidelines of medical societies.

RESULTS

Bacterial vaginosis (BV) is a dysbiosis resulting in an imbalance in the vaginal flora through the multiplication of anaerobic bacteria and jointly of a disappearance of well-known protective Lactobacilli. His diagnosis is based on clinical Amsel criteria and/or a Gram stain with establishment of the Nugent score. The prevalence of the BV extraordinarily varies according to ethnic and/or geographical origin (4-58 %), in France, it is close to 7 % in the first trimester of pregnancy (EL2). The link between BV and spontaneous premature delivery is low with an odds ratio between 1.5 and 2 in the most recent studies (EL3). Metronidazole or clindamycin is effective to treat BV (EL3). It is recommended to prescribe one of these antibiotics in the case of symptomatic BV (Professional Consensus). The testing associated with the treatment of BV in the global population showed no benefit in the prevention of the risk of spontaneous preterm delivery (EL2). Concerning low-risk asymptomatic population (defined by the absence of antecedent of premature delivery), it has been failed profit to track and treat the BV in the prevention of the risk of spontaneous preterm delivery (EL1). Concerning the high-risk population (defined by a history of preterm delivery), it has been failed profit to track and treat the VB in the prevention of the risk of spontaneous preterm delivery (EL3). However, in the sub population of patients with a history of preterm delivery occurred in a context of materno-fetal bacterial infection, there may be a benefit to detect and treat early and systematically genital infection, and in particular the BV (Professional Consensus).

CONCLUSION

The screening and treatment of BV during pregnancy in asymptomatic low-risk population is not recommended in the prevention of the risk of spontaneous preterm delivery (grade A). In the population at high risk with the only notion of antecedent of premature delivery, screening and treatment of the BV is not recommended (grade C).

The role of the bacterial microbiota on reproductive and pregnancy health

Recent assessments have examined the composition of bacterial communities influencing reproductive, pregnancy and infant health. The Microbiome Project has made great strides in sequencing the microbiome and identifying the vast communities of microorganisms that inhabit our bodies and much work continues to examine the individual contribution of bacteria on health and disease to inform future therapies. This review explores the current literature outlining the contribution of important bacteria on reproductive health among sexually active men and women, outlines gaps in current research to determine causal and interventional relationships, and suggests future research initiatives. Novel treatments options to reduce adverse outcomes must recognize the heterogeneity of the bacteria within the microbiome and adequately assess long-term benefits in reducing disease burden and re-establishing a healthy Lactobacillus-dominant state. Recognizing other reservoirs outside of the lower genital track and within sexual partners as well as genetic and individual moderators may be most important for long-term cure and reduction of disease. It will be important to develop useful screening tools and comprehensively examine novel therapeutic options to promote the long-term reduction of high-risk bacteria and the re-establishment of healthy bacterial levels to considerably improve outcomes among pregnant women and sexually active men and women.

Evaluation of the vaginal flora in pregnant women receiving opioid maintenance therapy: a matched case-control study

Background

Vaginal infections are a risk factor for preterm delivery. In this study, we sought to evaluate the vaginal flora of pregnant women receiving opioid maintenance therapy (OMT) in comparison to non-dependent, non-maintained controls.

Methods

A total of 3763 women with singleton pregnancies who underwent routine screening for asymptomatic vaginal infections between 10 + 0 and 16 + 0 gestational weeks were examined. Vaginal smears were Gram-stained, and microscopically evaluated for bacterial vaginosis, candidiasis, and trichomoniasis. In a retrospective manner, data of 132 women receiving OMT (cases) were matched for age, ethnicity, parity, education, previous preterm delivery, and smoking status to the data of 3631 controls. The vaginal flora at antenatal screening served as the primary outcome measure. Secondary outcome measures were gestational age and birth weight.

Results

In the OMT group, 62/132 (47 %) pregnant women received methadone, 39/132 (29.5 %) buprenorphine, and 31/132 (23.5 %) slow-release oral morphine. Normal or intermediate flora was found in 72/132 OMT women (54.5 %) and 2865/3631 controls [78.9 %; OR 0.49 (95 % CI, 0.33–0.71); p < 0.001]. Candidiasis occurred more frequently in OMT women than in controls [OR 2.11 (95 % CI, 1.26–3.27); p < 0.001]. Findings were inconclusive regarding bacterial vaginosis (± candidiasis) and trichomoniasis. Compared to infants of the control group, those of women with OMT had a lower mean birth weight [MD −165.3 g (95 % CI, −283.6 to −46.9); p = 0.006].

Conclusions

Pregnant women with OMT are at risk for asymptomatic vaginal infections. As recurrent candidiasis is associated with preterm delivery, the vulnerability of this patient population should lead to consequent antenatal infection screening at early gestation.

Electronic supplementary material

The online version of this article (doi:10.1186/s12884-016-1003-z) contains supplementary material, which is available to authorized users.

Cervicovaginal Microbiomes-Threats and Possibilities

The microbiome of the vagina has universal traits that override race, diet, lifestyle, and socioeconomic status. While five community state types have been proposed, the actual number is likely closer to ten. Nevertheless, while lactobacilli dominate in health for most women, a highly diverse community or single pathogens are associated with morbidity. The fact that four or five Lactobacillus species are dominant in healthy women worldwide, raises questions of why they evolved in this niche, what they are doing, and how their apparent protective properties can be harnessed? This opinion article explores this universality, elements of lactobacilli that may imprint women's health and that of their offspring, and proposes key areas for future study.

Relationship between Intrauterine Bacterial Infection and Early Embryonic Developmental Arrest

Background:

Early embryonic developmental arrest is the most commonly understudied adverse outcome of pregnancy. The relevance of intrauterine infection to spontaneous embryonic death is rarely studied and remains unclear. This study aimed to investigate the relationship between intrauterine bacterial infection and early embryonic developmental arrest.

Methods:

Embryonic chorion tissue and uterine swabs for bacterial detection were obtained from 33 patients who underwent artificial abortion (control group) and from 45 patients who displayed early embryonic developmental arrest (trial group).

Results:

Intrauterine bacterial infection was discovered in both groups. The infection rate was 24.44% (11/45) in the early embryonic developmental arrest group and 9.09% (3/33) in the artificial abortion group. Classification analysis revealed that the highest detection rate for Micrococcus luteus in the early embryonic developmental arrest group was 13.33% (6/45), and none was detected in the artificial abortion group. M. luteus infection was significantly different between the groups (P < 0.05 as shown by Fisher's exact test). In addition, no correlation was found between intrauterine bacterial infection and history of early embryonic developmental arrest.

Conclusions:

M. luteus infection is related to early embryonic developmental arrest and might be one of its causative factors.

Impact of Bacterial Vaginosis on Perineal Tears during Delivery: A Prospective Cohort Study

Objective

Long term effects of perineal tears pose a major worldwide health issue for women during delivery. Since bacterial vaginosis is related to major obstacles in obstetrics the aim of this study was to determine the relationship between bacterial vaginosis and the occurrence of perineal tears during vaginal delivery.

Methods

Between June 2013 and December 2013 pregnant women delivering after 37 weeks were recruited at one University hospital / tertiary care referral center in the course of this single-center, prospective cohort study. Bacterial vaginosis was assessed according to Nugent score method. Logistic-regression model was used to estimate odds ratios, adjusted for other risk factors to test the relationship between bacterial vaginosis and the occurrence of 1st to 4th degree perineal tears in women undergoing vaginal delivery.

Results

A total of 728 woman were included, 662 analyzed with a complete Nugent Score of the vaginal swab. The prevalence of 1st to 4th degree perineal tears was 35.8% (95% Confidence Interval (95%CI) = [32.2; 39.6]). The presence of BV was not significantly associated to the incidence of perineal tears neither in the univariate analysis (crude Odds Ratio = 1.43; 95%CI = [0.79; 2.60]; p = 0.235) nor in the multivariate analysis (adjusted Odds Ratio = 1.65; 95%CI = [0.81; 3.36]; p = 0.167). Instrumental delivery was the most important risk factor for perineal lacerations.

Conclusions

There is no evidence that vaginosis is a risk factor for vaginal tears.

Trial Registration

ClinicalTrials.gov N° NCT01822782

Screen-and-treat program by point-of-care of Atopobium vaginae and Gardnerella vaginalis in preventing preterm birth (AuTop trial): study protocol for a randomized controlled trial

BACKGROUND

International recommendations in favor of screening for vaginal infection in pregnancy are based on heterogeneous criteria. In most developed countries, the diagnosis of bacterial vaginosis is only recommended for women with high-risk of preterm birth. The Nugent score is currently used, but molecular quantification tools have recently been reported with a high sensitivity and specificity. Their value for reducing preterm birth rates and related complications remains unexplored. This trial was designed to assess the cost-effectiveness of a systematic screen-and-treat program based on a point-of-care technique for rapid molecular diagnosis, immediately followed by an appropriate antibiotic treatment, to detect the presence of abnormal vaginal flora (specifically, Atopobium vaginae and Gardnerella vaginalis) before 20 weeks of gestation in pregnant women in France. We hypothesized that this program would translate into significant reductions in both the rate of preterm births and the medical costs associated with preterm birth.

METHODS/DESIGN

A multicenter, open-label randomized controlled trial (RCT) will be conducted in which 20 French obstetrics and gynecology centers will recruit eligible pregnant women at less than 20 weeks gestation with singleton pregnancy and with a low-risk factor for preterm birth. Interventions will include a) an experimental group that will receive a systematic rapid screen-and-treat program from a point-of-care analysis using a molecular quantification method and b) a control group that will receive usual care management. Randomization will be in a 1:1 allocation ratio. The primary endpoint that will be assessed over a period of 12 months will be the incremental cost-effectiveness ratio (ICER) expressed as cost per avoided preterm birth before 37 weeks. Secondary endpoints will include ICER per avoided preterm birth before 24, 28 and 32 weeks, obstetrical outcomes, neonatal outcomes, rates of treatment failure and recurrence episodes for positive women. Uncertainty surrounding these estimates will be addressed using nonparametric bootstrapping and represented using cost-effectiveness acceptability curves. A total of 6,800 pregnant women will be included.

DISCUSSION

This appropriate randomized controlled design will provide insight into the cost-effectiveness and therefore the potential cost savings of a rapid screen-and-treat strategy for molecular abnormal vaginal flora in pregnant women. National and international recommendations could be updated based on the findings of this study.

TRIAL REGISTRATION

ClinicalTrials.gov: NCT02288832 (registration date: 30 October 2014); Eudract: 2014-001559-22.

Influence of Biofilm Formation by Gardnerella vaginalis and Other Anaerobes on Bacterial Vaginosis

Bacterial vaginosis (BV) is the worldwide leading vaginal disorder among women of reproductive age. BV is characterized by the replacement of beneficial lactobacilli and the augmentation of anaerobic bacteria. Gardnerella vaginalis is a predominant bacterial species, but BV is also associated with other numerous anaerobes, such as Atopobium vaginae, Mobiluncus mulieris, Prevotella bivia, Fusobacterium nucleatum, and Peptoniphilus species. Currently, the role of G. vaginalis in the etiology of BV remains a matter of controversy. However, it is known that, in patients with BV, a biofilm is usually formed on the vaginal epithelium and that G. vaginalis is typically the predominant species. So, the current paradigm is that the establishment of a biofilm plays a key role in the pathogenesis of BV. This review provides background on the influence of biofilm formation by G. vaginalis and other anaerobes, from the time of their initial adhesion until biofilm formation, in the polymicrobial etiology of BV and discusses the commensal and synergic interactions established between them to understand the phenotypic shift of G. vaginalis biofilm formation to BV establishment.