Relationship of specific vaginal bacteria and bacterial vaginosis treatment failure in women who have sex with women

Vaginal Lactobacillus fatty acid response mechanisms reveal a metabolite-targeted strategy for bacterial vaginosis treatment

Bacterial vaginosis (BV), a common syndrome characterized by Lactobacillus-deficient vaginal microbiota, is associated with adverse health outcomes. BV often recurs after standard antibiotic therapy in part because antibiotics promote microbiota dominance by Lactobacillus iners instead of Lactobacillus crispatus, which has more beneficial health associations. Strategies to promote L. crispatus and inhibit L. iners are thus needed. We show that oleic acid (OA) and similar long-chain fatty acids simultaneously inhibit L. iners and enhance L. crispatus growth. These phenotypes require OA-inducible genes conserved in L. crispatus and related lactobacilli, including an oleate hydratase (ohyA) and putative fatty acid efflux pump (farE). FarE mediates OA resistance, while OhyA is robustly active in the vaginal microbiota and enhances bacterial fitness by biochemically sequestering OA in a derivative form only ohyA-harboring organisms can exploit. OA promotes L. crispatus dominance more effectively than antibiotics in an in vitro BV model, suggesting a metabolite-based treatment approach.

Comparison of the urinary microbiome in men who have sex with men with and without Chlamydia trachomatis infection

PURPOSE

The urinary tract is colonized by microbial communities that impact urinary health. Previous studies have suggested that the bacterial composition of the male urinary microbiota is related to STIs. This study assessed the bacterial composition of the urinary microbiome in South African MSM with and without C. trachomatis.

METHODS

This study used urine samples from MSM attending care at the King Edward VIII hospital and the Aurum Institute in Durban, South Africa. A total of 200 samples were tested for C. trachomatis infection using the Applied Biosystems™ TaqMan® Assays. Urinary microbiomes of 23 samples were characterized using 16 S rRNA (V3 and V4) gene sequencing on the Illumina MiSeq platform.

RESULTS

Bacterial taxonomic analysis showed a high abundance of Streptococcus, Corynebacterium, and Staphylococcus in all the sequenced samples. Moreover, Prevotella and Lactobacillus were detected in urine samples of MSM. Alpha diversity metrics showed a slight increase in microbial diversity in C. trachomatis positive samples; however, this was not significant (ANOVA, P > 0.05). Principal coordinates analysis (PCoA) showed that the microbiome of C. trachomatis infected MSM was not clearly different from those uninfected. Distinct bacterial communities were not detected between positive and negative samples (PERMANOVA F1,22= 1.0284, R2 = 0.047%, P = 0.385).

CONCLUSION

Most microbiome studies on MSM to date have focused on the gut microenvironment. Few studies, however, have provided data regarding the normal composition of the male urethral microbiomes or if these microbiomes are associated with male STIs. This study adds to the growing body of knowledge highlighting the urinary microbiome in MSM.

Anaerobic bacteria in chronic wounds: Roles in disease, infection and treatment failure

Infection is among the most common factors that impede wound healing, yet standard treatments routinely fail to resolve chronic wound infections. The chronic wound environment is largely hypoxic/anoxic, and wounds are predominantly colonised by facultative and obligate anaerobic bacteria. Oxygen (O2) limitation is an underappreciated driver of microbiota composition and behaviour in chronic wounds. In this perspective article, we examine how anaerobic bacteria and their distinct physiologies support persistent, antibiotic-recalcitrant infections. We describe the anaerobic energy metabolisms bacteria rely on for long-term survival in the wound environment, and why many antibiotics become less effective under hypoxic conditions. We also discuss obligate anaerobes, which are among the most prevalent taxa to colonise chronic wounds, yet their potential roles in influencing the microbial community and wound healing have been overlooked. All of the most common obligate anaerobes found in chronic wounds are opportunistic pathogens. We consider how these organisms persist in the wound environment and interface with host physiology to hinder wound healing processes or promote chronic inflammation. Finally, we apply our understanding of anaerobic physiologies to evaluate current treatment practices and to propose new strategies for treating chronic wound infections.

Vaginal Lactobacillus fatty acid response mechanisms reveal a novel strategy for bacterial vaginosis treatment

Bacterial vaginosis (BV), a common syndrome characterized by Lactobacillus-deficient vaginal microbiota, is associated with adverse health outcomes. BV often recurs after standard antibiotic therapy in part because antibiotics promote microbiota dominance by Lactobacillus iners instead of Lactobacillus crispatus, which has more beneficial health associations. Strategies to promote L. crispatus and inhibit L. iners are thus needed. We show that oleic acid (OA) and similar long-chain fatty acids simultaneously inhibit L. iners and enhance L. crispatus growth. These phenotypes require OA-inducible genes conserved in L. crispatus and related species, including an oleate hydratase (ohyA) and putative fatty acid efflux pump (farE). FarE mediates OA resistance, while OhyA is robustly active in the human vaginal microbiota and sequesters OA in a derivative form that only ohyA-harboring organisms can exploit. Finally, OA promotes L. crispatus dominance more effectively than antibiotics in an in vitro model of BV, suggesting a novel approach for treatment.

Association of Chlamydia trachomatis burden with the vaginal microbiota, bacterial vaginosis, and metronidazole treatment

Bacterial vaginosis (BV), a dysbiosis of the vaginal microbiota, is a common coinfection with Chlamydia trachomatis (Ct), and BV-associated bacteria (BVAB) and their products have been implicated in aiding Ct evade natural immunity. Here, we determined if a non-optimal vaginal microbiota was associated with a higher genital Ct burden and if metronidazole, a standard treatment for BV, would reduce Ct burden or aid in natural clearance of Ct infection. Cervicovaginal samples were collected from women at enrollment and, if testing positive for Ct infection, at a follow-up visit approximately one week later. Cervical Ct burden was assessed by inclusion forming units (IFU) and Ct genome copy number (GCN), and 16S rRNA gene sequencing was used to determine the composition of the vaginal microbiota. We observed a six-log spectrum of IFU and an eight-log spectrum of GCN in our study participants at their enrollment visit, but BV, as indicated by Amsel's criteria, Nugent scoring, or VALENCIA community state typing, did not predict infectious and total Ct burden, although IFU : GCN increased with Amsel and Nugent scores and in BV-like community state types. Ct burden was, however, associated with the abundance of bacterial species in the vaginal microbiota, negatively with Lactobacillus crispatus and positively with Prevotella bivia. Women diagnosed with BV were treated with metronidazole, and Ct burden was significantly reduced in those who resolved BV with treatment. A subset of women naturally cleared Ct infection in the interim, typified by low Ct burden at enrollment and resolution of BV. Abundance of many BVAB decreased, and Lactobacillus increased, in response to metronidazole treatment, but no changes in abundances of specific vaginal bacteria were unique to women who spontaneously cleared Ct infection.

The Oral Microbiome Profile of Water Polo Players Aged 16-20

OBJECTIVES

Chlorine has a strong antibacterial property and is the disinfectant most frequently used in swimming pools. Therefore, the microbiota community in the oral cavity of those who practice water sports is assumed to be special due to their regular immersion in water. Adverse changes in the composition of oral cavity microbiota may have serious health consequences. We aimed to compare the oral microbiome between water polo players and non-athletes. We hypothesized that the oral cavity microbiota community differed between water polo players and non-athletes.

MATERIALS AND METHODS

Altogether, 124 water polo players (62 males and 62 females, aged between 9 and 20 years) and 16 non-athlete youths (control group, eight males and eight females, aged between 16 and 20 years, mean age + SD = 17.1 + 1.4 years) who participated in body structure examinations voluntarily agreed to participate in the study. In a randomly selected subsample of water polo players (n: 29, aged between 16 and 20 years, mean age + SD = 17.3 + 1.0 years), saliva samples were also collected. Saliva samples were collected from all non-athlete youths (n: 16, aged between 16 and 20 years). The oral microbiome was determined from a saliva sample, and DNA was isolated using the QIAmp DNA Blood Mini Kit. The 16S rRNA gene amplicon sequencing method was used to analyze the microbiome community. PCR primers were trimmed from the sequence reads with Cutadapt. R library DADA2 was used to process reads in the abundance analysis.

RESULTS

In general, Streptococcus, Veilonella, and Prevotella genera constituted more than 50% of the oral microbiome community in the two participant groups combined (n = 45). The oral microbial profile had significant sexual dimorphism and differed between water polo players and the non-athletes. Compared to females, males had a higher (p < 0.05) relative abundance of the Atopobium (medium effect size) and Pravotella_7 (very large effect size) genera and a lower (p < 0.05) relative abundance of the Fusobacterium (large effect size), Gemella (large effect size), and Streptococcus (large effect size) genera. Compared to non-athletes, water polo players had higher (p < 0.05, medium effect size) relative abundance of the genus Veillonella and lower (p < 0.05, large effect size) relative abundance of the genus Gemella.

CONCLUSIONS

The results suggest that regular water training can unfavorably alter the composition of the oral microbial community.

Amygdalobacter indicium gen. nov., sp. nov., and Amygdalobacter nucleatus sp. nov., gen. nov.: novel bacteria from the family Oscillospiraceae isolated from the female genital tract

Four obligately anaerobic Gram-positive bacteria representing one novel genus and two novel species were isolated from the female genital tract. Both novel species, designated UPII 610-JT and KA00274T, and an additional isolate of each species were characterized utilizing biochemical, genotypic and phylogenetic analyses. All strains were non-motile and non-spore forming, asaccharolytic, non-cellulolytic and indole-negative coccobacilli. Fatty acid methyl ester analysis for UPII 610-JT and KA00274T and additional isolates revealed C16 : 0, C18 : 0, C18:1ω9c and C18:2ω6,9c to be the major fatty acids for both species. UPII 610-JT had a 16S rRNA gene sequence similarity of 99.4 % to an uncultured clone sequence (AY724740) designated as Bacterial Vaginosis Associated Bacterium 2 (BVAB2). KA00274T had a 16S rRNA gene sequence similarity of 96.5 % to UPII 610-JT. Whole genomic DNA mol% G+C content was 42.2 and 39.3 % for UPII 610-JT and KA00274T, respectively. Phylogenetic analyses indicate these isolates represent a novel genus and two novel species within the Oscillospiraceae family. We propose the names Amygdalobacter indicium gen. nov., sp. nov., for UPII 610-JT representing the type strain of this species (=DSM 112989T, =ATCC TSD-274T) and Amygdalobacter nucleatus gen. nov., sp. nov., for KA00274T representing the type strain of this species (=DSM 112988T, =ATCC TSD-275T).

Urinary Glycosaminoglycans Are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women

Glycosaminoglycans (GAGs) are linear, negatively charged polysaccharides composed of repeating disaccharide units of uronic acid and amino sugars. The luminal surface of the bladder epithelium is coated with a GAG layer. These urothelial GAGs are thought to provide a protective barrier and serve as a potential interaction site with the urinary microbiome (urobiome). Previous studies have profiled urinary GAG composition in mixed cohorts, but the urinary GAG composition in postmenopausal women remains undefined. To investigate the relationship between GAGs and recurrent urinary tract infection (rUTI), we profiled urinary GAGs in a controlled cohort of postmenopausal women. We found that chondroitin sulfate (CS) is the major urinary GAG in postmenopausal women and that urinary CS was elevated in women with active rUTI. We also associated urinary GAGs with urobiome composition and identified bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas somerae, and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid, and bacterial species associated with vaginal dysbiosis were negatively correlated with urinary CS. Altogether, this work defines changes in urinary GAG composition associated with rUTI and identifies new associations between urinary GAGs and the urobiome that may play a role in rUTI pathobiology.

Urinary Glycosaminoglycans are Associated with Recurrent UTI and Urobiome Ecology in Postmenopausal Women

Glycosaminoglycans (GAGs) are linear, negatively charged polysaccharides composed of repeating disaccharide units of uronic acid and amino sugars. The luminal surface of the bladder epithelium is coated with a GAG layer. These urothelial GAGs are thought to provide a protective barrier and serve as a potential interaction site with the urinary microbiome (urobiome). Previous studies have profiled urinary GAG composition in mixed cohorts, but the urinary GAG composition in postmenopausal women remains undefined. To investigate the relationship between GAGs and recurrent UTI (rUTI), we profiled urinary GAGs in a controlled cohort of postmenopausal women. We found that chondroitin sulfate (CS) is the major urinary GAG in postmenopausal women and that urinary CS was elevated in women with active rUTI. We also associated urinary GAGs with urobiome composition and identified bacterial species that significantly associated with urinary GAG concentration. Corynebacterium amycolatum, Porphyromonas somerae , and Staphylococcus pasteuri were positively associated with heparin sulfate or hyaluronic acid and bacterial species associated with vaginal dysbiosis were negatively correlated to urinary CS. Altogether, this work defines changes in urinary GAG composition associated with rUTI and identifies new associations between urinary GAGs and the urobiome that may play a role in rUTI pathobiology.

Treatment Success Following Standard Antibiotic Treatment for Bacterial Vaginosis Is Not Associated With Pretreatment Genital Immune or Microbial Parameters

Background

Bacterial vaginosis (BV) is a proinflammatory genital condition associated with adverse reproductive health outcomes, including increased HIV incidence. However, BV recurrence rates are high after standard antibiotic treatment. While the composition of the vaginal microbiota before BV treatment may be linked to BV recurrence, it is unclear whether the preceding genital immune milieu is predictive of treatment success.

Methods

Here we assessed whether baseline vaginal soluble immune factors or the composition of the vaginal microbiota predicted treatment success 1 month after metronidazole treatment in 2 separate cohorts of women with BV, 1 in the United States and 1 in Kenya; samples within 48 hours of BV treatment were also available for the US cohort.

Results

Neither soluble immune factors nor the composition of the vaginal microbiota before BV treatment was associated with treatment response in either cohort. In the US cohort, although the absolute abundances of key vaginal bacterial taxa pretreatment were not associated with treatment response, participants with sustained BV clearance had a more pronounced reduction in the absolute abundance of Gardnerella vaginalis immediately after treatment.

Conclusions

Pretreatment immune and microbial parameters were not predictive of BV treatment success in these clinical cohorts.

Recurrent urinary tract infection and estrogen shape the taxonomic ecology and function of the postmenopausal urogenital microbiome

Postmenopausal women are severely affected by recurrent urinary tract infection (rUTI). The urogenital microbiome is a key component of the urinary environment. However, changes in the urogenital microbiome underlying rUTI susceptibility are unknown. Here, we perform shotgun metagenomics and advanced culture on urine from a controlled cohort of postmenopausal women to identify urogenital microbiome compositional and function changes linked to rUTI susceptibility. We identify candidate taxonomic biomarkers of rUTI susceptibility in postmenopausal women and an enrichment of lactobacilli in postmenopausal women taking estrogen hormone therapy. We find robust correlations between Bifidobacterium and Lactobacillus and urinary estrogens in women without urinary tract infection (UTI) history. Functional analyses reveal distinct metabolic and antimicrobial resistance gene (ARG) signatures associated with rUTI. Importantly, we find that ARGs are enriched in the urogenital microbiomes of women with rUTI history independent of current UTI status. Our data suggest that rUTI and estrogen shape the urogenital microbiome in postmenopausal women.

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

Bacterial vaginosis (BV) is associated with a state of vaginal dysbiosis typically involving depletion of otherwise dominant populations of Lactobacillus. The causes of this microbial succession are not known; there may be multiple causes. Standard treatment includes oral metronidazole, which typically restores Lactobacillus species to dominance. However, recurrence rates are high; recurrent BV patients recur 3–4 times annually and are often refractory to treatment. Our previous qPCR-based study of recurrent BV patients pointed to putatively more virulent species of Gardnerella that were associated with refractory responses to oral metronidazole, and less robust recovery of Lactobacillus species associated with recurrence after an initial period of remission. However, these associations did not account for outcomes in all patients, suggesting that other bacterial species were involved. In this follow-up study, we sequenced the V4 domain of 16S rRNA sequences of 41of these same patients pre- and posttreatment. Overall compositions among pretreatment clinical outcome groups were not different, although alpha diversity significantly decreased: refractory > recurrent > remission. Combinations of key species were associated with and prognostic for outcome. Higher pretreatment abundance of Megasphaera lornae together with lower abundance of Gardnerella Gsp07 and Finegoldia magna predicted long term remission after oral metronidazole. Furthermore, a subset of refractory patients that did not have high levels of Gardnerella Gsp07, instead had elevated levels of alternative species including Atopobium vaginae, Mageeibacillus indolicus (BVAB3), and Prevotella timonensis. Patients who recurred after transient remission had elevated abundance of species including Atopobium vaginae, Gardnerella, and Aerococcus christensenii, compared to long-term remission patients. Core bacterial species among refractory patients did not change in abundance after metronidazole, suggesting resistance or tolerance, in contrast to the loss in abundance of the same species among recurrent or remission patients. These findings have potential prognostic and therapeutic implications.

Cysteine dependence of Lactobacillus iners is a potential therapeutic target for vaginal microbiota modulation

Vaginal microbiota composition affects many facets of reproductive health. Lactobacillus iners-dominated microbial communities are associated with poorer outcomes, including higher risk of bacterial vaginosis (BV), compared with vaginal microbiota rich in L. crispatus. Unfortunately, standard-of-care metronidazole therapy for BV typically results in dominance of L. iners, probably contributing to post-treatment relapse. Here we generate an L. iners isolate collection comprising 34 previously unreported isolates from 14 South African women with and without BV and 4 previously unreported isolates from 3 US women. We also report an associated genome catalogue comprising 1,218 vaginal Lactobacillus isolate genomes and metagenome-assembled genomes from >300 women across 4 continents. We show that, unlike L. crispatus, L. iners growth is dependent on L-cysteine in vitro and we trace this phenotype to the absence of canonical cysteine biosynthesis pathways and a restricted repertoire of cysteine-related transport mechanisms. We further show that cysteine concentrations in cervicovaginal lavage samples correlate with Lactobacillus abundance in vivo and that cystine uptake inhibitors selectively inhibit L. iners growth in vitro. Combining an inhibitor with metronidazole promotes L. crispatus dominance of defined BV-like communities in vitro by suppressing L. iners growth. Our findings enable a better understanding of L. iners biology and suggest candidate treatments to modulate the vaginal microbiota to improve reproductive health for women globally.

Log (Lactobacillus crispatus/ Gardnerella vaginalis): a new indicator of diagnosing bacterial vaginosis

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. Gardnerella vaginalis, Atopobium vaginae, Lactobacillus, Megasphaera 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 Lactobacillus crispatus as the numerator and other BV-related bacteria as the denominator. Four new indicators were found. Of these, log L. crispatus/G. vaginalis (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.

Abbreviation: log L. crispatus/G. vaginalis (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).

Bacterial Vaginosis: What Do We Currently Know?

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 Lactobacilli. 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 Lactobacilli by anaerobic bacteria such as Gardnerella vaginalis, Atopobium vaginae, Ureaplasma urealyticum, Mycoplasma hominis, 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.

Developing an algorithm for the diagnosis of abnormal vaginal discharge in a dutch clinical setting: a pilot study

Abnormal vaginal discharge may be caused by bacterial vaginosis, vulvovaginal candidiasis, trichomoniasis and/or aerobic vaginitis. For the development of a diagnostic algorithm, tree-based classification analysis was performed on symptoms, signs and bedside test results of 56 patients, and laboratory tests (culture, Nugent score, qPCRs) were compared. Amplicon sequencing of the 16S rRNA gene was used as reference test for bacterial vaginosis and aerobic vaginitis, culture for vulvovaginal candidiasis and qPCR for trichomoniasis. For bacterial vaginosis, the best diagnostic algorithm was to screen at the bedside with a pH and odour test and if positive, to confirm by qPCR (sensitivity 94%; specificity 97%) rather than Nugent score (sensitivity of 59%; specificity 97%; P = 0.031). The analysis for the other infections was less conclusive due to the low number of patients with these infections. For bacterial vaginosis, the developed algorithm is sensitive, specific, and reduces the need for laboratory tests in 50% of the patients.

Megasphaera lornae sp. nov., Megasphaera hutchinsoni sp. nov., and Megasphaera vaginalis sp. nov.: novel bacteria isolated from the female genital tract

Six strictly anaerobic Gram-negative bacteria representing three novel species were isolated from the female reproductive tract. The proposed type strains for each species were designated UPII 199-6^T, KA00182^T and BV3C16-1^T. Phylogenetic analyses based on 16S rRNA gene sequencing indicated that the bacterial isolates were members of the genus Megasphaera. UPII 199-6^T and KA00182^T had 16S rRNA gene sequence identities of 99.9 % with 16S rRNA clone sequences previously amplified from the human vagina designated as Megasphaera type 1 and Megasphaera type 2, members of the human vaginal microbiota associated with bacterial vaginosis, preterm birth and HIV acquisition. UPII 199-6^T exhibited sequence identities ranging from 92.9 to 93.6 % with validly named Megasphaera isolates and KA00182^T had 16S rRNA gene sequence identities ranging from 92.6-94.2 %. BV3C16-1^T was most closely related to Megasphaera cerevisiae with a 16S rRNA gene sequence identity of 95.4 %. Cells were coccoid or diplococcoid, non-motile and did not form spores. Genital tract isolates metabolized organic acids but were asaccharolytic. The isolates also metabolized amino acids. The DNA G+C content for the genome sequences of UPII 199-6^T, KA00182^T and BV3C16-1^T were 46.4, 38.9 and 49.8 mol%, respectively. Digital DNA-DNA hybridization and average nucleotide identity between the genital tract isolates and other validly named Megasphaera species suggest that each isolate type represents a new species. The major fatty acid methyl esters include the following: C_12 : 0, C_16 : 0, C_16 : 0 dimethyl acetal (DMA) and summed feature 5 (C_15 : 0 DMA and/or C_14 : 0 3-OH) in UPII 199-6^T; C_16 : 0 and C_16 : 1 cis 9 in KA00182^T; C_12 : 0; C_14 : 0 3-OH; and summed feature 5 in BV3C16-1^T. The isolates produced butyrate, isobutyrate, and isovalerate but there were specific differences including production of formate and propionate. Together, these data indicate that UPII 199-6^T, KA00182^T and BV3C16-1^T represent novel species within the genus Megasphaera. We propose the following names: Megasphaera lornae sp. nov. for UPII 199-6^T representing the type strain of this species (=DSM 111201^T=ATCC TSD-205^T), Megasphaera hutchinsoni sp. nov. for KA00182^T representing the type strain of this species (=DSM 111202^T=ATCC TSD-206^T) and Megasphaera vaginalis sp. nov. for BV3C16-1^T representing the type strain of this species (=DSM 111203^T=ATCC TSD-207^T).

Current and Future Trends in the Laboratory Diagnosis of Sexually Transmitted Infections

Sexually transmitted infections (STIs) continue to exert a considerable public health and social burden globally, particularly for developing countries. Due to the high prevalence of asymptomatic infections and the limitations of symptom-based (syndromic) diagnosis, confirmation of infection using laboratory tools is essential to choose the most appropriate course of treatment and to screen at-risk groups. Numerous laboratory tests and platforms have been developed for gonorrhea, chlamydia, syphilis, trichomoniasis, genital mycoplasmas, herpesviruses, and human papillomavirus. Point-of-care testing is now a possibility, and microfluidic and high-throughput omics technologies promise to revolutionize the diagnosis of STIs. The scope of this paper is to provide an updated overview of the current laboratory diagnostic tools for these infections, highlighting their advantages, limitations, and point-of-care adaptability. The diagnostic applicability of the latest molecular and biochemical approaches is also discussed.

Depiction of Vaginal Microbiota in Women With High-Risk Human Papillomavirus Infection

Persistent infection with the carcinogenic human papillomavirus (HPV) is a prerequisite for the progression of cervical lesions and cancer. A growing body of research has focused on the functional role of the vaginal microbiota in the persistence of HPV infection. Understanding the microbial composition and structure in women with high-risk (hr)-HPV infection may help reveal associations between the vaginal microbiota and HPV infection, and identify potential biomarkers. Our study investigated the vaginal microbial community in women with and without hr-HPV infection, by using 16s rRNA gene sequencing. We found that microbial perturbations occurred in the early phase of hr-HPV infection. Lactobacillus and Sporolactobacillus were decreased, while bacteria related to bacterial vaginosis (BV), such as Gardnerella, Prevotella, Dialister, Slackia, Actinomyces, Porphyromonas, Peptoniphilus, Anaerococcus, Peptostreptococcus, Streptococcus, Ureaplasma, Megasphaera, and Mycoplasma were increased. Our results could offer insights into the correlations between hr-HPV and the vaginal microbiota in the early infection period, and provide indications that the predominance of some BV-associated bacteria during hr-HPV infection may increase the risk for cervical neoplasia.

Vaginal Microbiome-Based Bacterial Signatures for Predicting the Severity of Cervical Intraepithelial Neoplasia

Although emerging evidence revealed that the gut microbiome served as a tool and as biomarkers for predicting and detecting specific cancer or illness, it is yet unknown if vaginal microbiome-derived bacterial markers can be used as a predictive model to predict the severity of CIN. In this study, we sequenced V3 region of 16S rRNA gene on vaginal swab samples from 66 participants (24 CIN 1−, 42 CIN 2+ patients) and investigated the taxonomic composition. The vaginal microbial diversity was not significantly different between the CIN 1− and CIN 2+ groups. However, we observed Lactobacillus amylovorus dominant type (16.7%), which does not belong to conventional community state type (CST). Moreover, a minimal set of 33 bacterial species was identified to maximally differentiate CIN 2+ from CIN 1− in a random forest model, which can distinguish CIN 2+ from CIN 1− (area under the curve (AUC) = 0.952). Among the 33 bacterial species, Lactobacillus iners was selected as the most impactful predictor in our model. This finding suggests that the random forest model is able to predict the severity of CIN and vaginal microbiome may play a role as biomarker.

Asymptomatic Bacterial Vaginosis: To Treat or Not to Treat?

Purpose of Review

The purpose of this review is to summarize current evidence for and against the treatment of asymptomatic bacterial vaginosis (BV) in women.

Recent Findings

Asymptomatic BV is common although its pathogenesis remains incompletely understood. In favor of treating asymptomatic BV is the large body of data supporting that it is sexually transmitted. Along these lines and similar to other STIs, treatment of BV, regardless of symptom status, should be considered to reduce adverse outcomes of infection (i.e. adverse birth outcomes, infertility, post-gynecologic surgery infections, etc.) and prevent further sexual transmission of BV pathogen(s) to sexual partners. One study has found that treatment of women with asymptomatic BV led to a significant reduction in incident chlamydial infections over a 6 month follow-up period, compared to observation-only women. Additionally, some women with asymptomatic BV actually have symptomatic BV but do not recognize these symptoms as an infection. Nevertheless, limitations of the trial regarding treatment of asymptomatic BV as well as the 2020 United States Preventative Task Force recommendation against screening and treatment of asymptomatic BV in pregnant women dampen enthusiasm for recommending treatment in this setting.

Summary

Treatment of asymptomatic BV remains controversial. Additional studies are needed to further investigate the pathogenesis of BV, which will directly influence advances in its diagnosis, treatment, and prevention.

Bacterial Communities Associated With Abnormal Nugent Score in Postmenopausal Versus Premenopausal Women

The Nugent score is the reference standard for bacterial vaginosis (BV) diagnosis but has not been validated in postmenopausal women. We compared relative abundances from 16S ribosomal RNA gene sequencing of vaginal microbiota with Nugent score in cohorts of premenopausal (n = 220) and postmenopausal (n = 144) women. In premenopausal women, 33 taxa were significantly correlated with Nugent score, including the classic BV-associated taxa Gardnerella, Atopobium, Sneathia, Megasphaera, and Prevotella. In postmenopausal women, 11 taxa were significantly associated with Nugent score, including Prevotella but no other BV-associated genera. High Nugent scores should not be used to infer BV in postmenopausal women.

Comparative analysis of Bacterial Vaginosis microbiota among pregnant and non-pregnant females and isolation of phages against Enterococcus faecalis, Enterococcus faecium, and Shigella flexneri strains

BACKGROUND AND OBJECTIVES

Bacterial vaginosis (BV) is the most common vaginal infection in women of reproductive age. It shifts the paradigms of the vagina from healthy, beneficial microbiota to facultative and strict anaerobes. BV remains one of the most arduous and controversial challenges in modern-day clinical microbiology because of its high prevalence and relapse rates. A lot of research has been carried out on it. Still, its etiology is unknown, which gave this infection global importance. The current study was designed to investigate and compare the microbiota of pregnant and non-pregnant females suffering from BV, and phages were isolated against BV microbiota.

MATERIAL AND METHODS

The samples were collected from the vagina by using a speculum, and swabs were streaked on different media to isolate bacteria. The microbiological analysis was performed by microscopy, biochemical testing, and antibiotic susceptibility was determined by using Metronidazole and Clindamycin. Furthermore, the phages were isolated and characterized against BV strains.

RESULTS AND CONCLUSION

The Gram staining showed high prevalence of Staphylococcus (36% vs. 33%), followed by Streptococcus (31% vs. 14%) and Enterococcus (7% vs. 14%) in non-pregnant and pregnant females' respectively. However, the exception was observed in non-pregnant BV positive females, who had Shigella flexneri in their samples. The antibiotic sensitivity showed Metronidazole was resistant against all BV microbiota, and Clindamycin showed susceptibility against 3 strains. Phages were isolated against three bacterial strains, i.e. E. faecalis, E. faecium, and S. flexneri. Bacterial reduction assay showed bacterial growth decreases in the presence of phage suspension, pH stability showed phages' maximum lytic activity at pH 7 for E. faecalis and E. faecium and pH 9 for S. flexneri. However, the thermal stability showed phages' highest lytic activity at 55 °C for E. faecalis, 70 °C for E. faecium, and 40 °C for S. flexneri. Phage genome isolation showed that all phages nucleic acid was DNA in nature and between 15 and 20kbp. SEM analysis showed they were circular in shape and might belong to the Podoviridae family. This study provides an understanding of pathogens involved in BV and helps the doctors to treat the patients accordingly. Furthermore, this study showed that Bacterial Vaginosis and BV secondary bacteria have associations. BV secondary microbiota is also involved in the pathogenesis of this infection, whereas bacteriophage therapy has the potential to be used as an alternative treatment to antibiotics.

Analysis of CRISPR-Cas systems in Gardnerella suggests its potential role in the mechanisms of bacterial vaginosis

Bacterial vaginosis (BV) is the principal cause of vaginal discharge among women, and it can lead to many comorbidities with a negative impact in women's daily activities. Despite the fact that the pathophysiological process of BV remains unclear, great advances had been achieved in determining consequences of the shift in the vaginal community, and it was defined that Gardnerella spp., plays a key role in the pathogenesis of BV. Interactions of vaginal phage communities and bacterial hosts may be relevant in eubiosis/dysbiosis states, so defense mechanisms in Gardnerella spp., against phage infections could be relevant in BV development. In this study, we analyzed CRISPR-Cas systems among the 13 Gardnerella species recently classified, considering that these systems act as prokaryotic immune systems against phages, plasmids, and other mobile genetic elements. In silico analyses for CRISPR-Cas systems mining over the 81 Gardnerella spp., strains genomes analyzed led to the identification of subtypes I-E and II-C. Spacers analyses showed a hypervariable region across species, providing a high resolution level in order to distinguish clonality in strains, which was supported with phylogenomic analyses based on Virtual Genomic Fingerprinting. Moreover, most of the spacers revealed interactions between Gardnerella spp., strains and prophages over the genus. Furthermore, virulence traits of the 13 species showed insights of potential niche specificity in the vaginal microbiome. Overall, our results suggest that the CRISPR-Cas systems in the genus Gardnerella may play an important role in the mechanisms of the development and maintenance of BV, considering that the Gardnerella species occupies different niches in the vaginal community; in addition, spacer sequences can be used for genotyping studies.

Behavioral Counseling Interventions to Prevent Sexually Transmitted Infections: Updated Evidence Report and Systematic Review for the US Preventive Services Task Force

IMPORTANCE

Increasing rates of preventable sexually transmitted infections (STIs) in the US pose substantial burdens to health and well-being.

OBJECTIVE

To update evidence for the US Preventive Services Task Force (USPSTF) on effectiveness of behavioral counseling interventions for preventing STIs.

DATA SOURCES

Studies from the previous USPSTF review (2014); literature published January 2013 through May 31, 2019, in MEDLINE, PubMed (for publisher-supplied records only), PsycINFO, and Cochrane Central Register of Controlled Trials. Ongoing surveillance through May 22, 2020.

STUDY SELECTION

Good- and fair-quality randomized and nonrandomized controlled intervention studies of behavioral counseling interventions for adolescents and adults conducted in primary care settings were included. Studies with active comparators only or limited to individuals requiring specialist care for STI risk-related comorbidities were excluded.

DATA EXTRACTION AND SYNTHESIS

Dual risk of bias assessment, with inconsistent ratings adjudicated by a third team member. Study data were abstracted into prespecified forms. Pooled odds ratios (ORs) were estimated using the DerSimonian and Laird method or the restricted maximum likelihood method with Knapp-Hartung adjustment.

MAIN OUTCOMES AND MEASURES

Differences in STI diagnoses, self-reported condom use, and self-reported unprotected sex at 3 months or more after baseline.

RESULTS

The review included 37 randomized trials and 2 nonrandomized controlled intervention studies (N = 65 888; 13 good-quality, 26 fair-quality) recruited from primary care settings in the US. Study populations were composed predominantly of heterosexual adolescents and young adults (12 to 25 years), females, and racial and ethnic minorities at increased risk for STIs. Nineteen trials (n = 52 072) reported STI diagnoses as outcomes (3 to 17 months' follow-up); intervention was associated with reduced STI incidence (OR, 0.66 [95% CI, 0.54-0.81; I2 = 74%]). Absolute differences in STI acquisition between groups varied widely depending on baseline population STI risk and intervention effectiveness, ranging from 19% fewer to 4% more people acquiring STI. Thirty-four trials (n = 21 417) reported behavioral change outcomes. Interventions were associated with self-reported behavioral change (eg, increased condom use) that reduce STI risk (OR, 1.31 [95% CI, 1.10-1.56; I2 = 40%, n = 5253). There was limited evidence on persistence of intervention effects beyond 1 year. No harms were identified in 7 studies (n = 3458) reporting adverse outcomes.

CONCLUSIONS AND RELEVANCE

Behavioral counseling interventions for individuals seeking primary health care were associated with reduced incidence of STIs. Group or individual counseling sessions lasting more than 2 hours were associated with larger reductions in STI incidence, and interventions of shorter duration also were associated with STI prevention, although evidence was limited on whether the STI reductions associated with these interventions persisted beyond 1 year.

Changes in the vaginal microbiota across a gradient of urbanization

The vaginal microbiota of healthy women typically has low diversity, which increases after perturbations. Among these, lifestyle associated with certain sexual and antimicrobial practices may be associated with higher diversity. To test this hypothesis, we characterized the vaginal microbiota in the cervicovaginal and introital sites in sexually active Amerindians (N = 82) spanning urbanization, and in urban mestizos (N = 29), in the Venezuelan Amazonas. HPV status was also considered. Sampling was performed in an urban gradient from remote villages to a town, and women were individually classified by the degree of urbanization (low, medium, and high). Amerindian cervicovaginal and introital microbiota diversity were not associated with major changes in urbanization or ethnicity. There was a non-significant trend of increased diversity with urbanization, with a few taxa found overrepresented in urban Amerindians (Brevibacterium linens and Peptoniphilus lacrimalis) or mestizos (Mobiluncus mulieris and Prevotella sp.). Among all women, cervicovaginal and introital samples clustered, respectively, in four and two community state types (CSTs), where most profiles were dominated by Lactobacillus iners, Gardnerella vaginalis or were highly diverse profiles. HPV status did not associate with microbial diversity. In conclusion, no association was found between urban level and the vaginal microbiome in Amerindian women, and little difference was found between ethnicities. L. iners and high diversity profiles, associated with vaginal health outcomes, prevail in these populations.

[Literature review on studies of women who have sex with women]

Women who have sex with other women are a group that has been mostly invisible from public health policies. This category includes the group of lesbians, bisexual women, heterosexual behaviour, and homosexual practices, who have sexual relations with transsexual and transgender (trans) women and trans men who have sex with women. In the absence of a Spanish literature review of a study that addresses women who have sex with other women, a narrative bibliographic review was done using the PubMed/MEDLINE, Scopus, Dialnet, and Taylor and Francis databases. From a universe of 679 articles and after applying the inclusion criteria, 40 documents were analysed, from 1998 to 2019. Three meta-categories were identified (sexual education, the incidence of certain sexually transmitted infections, and aspects related to sexual practices), concerning prevention and risky behaviours. Women who have sex with other women are a particularly vulnerable group when it comes to sexually transmitted infections. These may include bacterial vaginitis, human papillomavirus and acquired immunodeficiency virus. Likewise, there is a lack of specific training and information in health and education professionals, as well as in women who have sex with other women.

Lessons from Suppressive Therapy and Periodic Presumptive Treatment for Bacterial Vaginosis

PURPOSE OF REVIEW

Suppressive therapy and periodic presumptive treatment (PPT) are distinct but related strategies that have been used to reduce the incidence of bacterial vaginosis (BV). Here, we review clinical trial evidence of the effectiveness of suppressive therapy and PPT to reduce BV, and discuss their roles for women who frequently experience symptomatic or asymptomatic BV.

RECENT FINDINGS

Among women who were recently and successfully treated for symptomatic BV, suppressive therapy with twice-weekly metronidazole gel for 16 weeks reduces the likelihood of recurrent symptomatic BV and is currently recommended by the Centers for Disease Control and Prevention for prevention of recurrent BV. The premise of PPT is to provide regimens used to treat BV at regular intervals to reduce the overall frequency of BV, regardless of symptoms. Three PPT trials were conducted using different routes (oral or intravaginal), doses, and frequencies of administration. Each trial demonstrated a significant reduction in BV over the course 12 months, ranging from a 10 to 45% decrease. PPT regimens that substantially reduce the frequency of BV over time could be evaluated in clinical trials to assess whether a reduced frequency of BV leads to subsequent reductions in BV-associated sequelae. While both suppressive therapy and PPT reduce BV, their impact wanes following cessation of the regimen. Given the high prevalence of BV globally and burden of adverse reproductive health outcomes among women with BV, there is a critical need for more effective treatments that produce durable shifts in the microbiota towards vaginal health.

Association Analysis on Recurrence of Bacterial Vaginosis Revealed Microbes and Clinical Variables Important for Treatment Outcome

To investigate the parameters associated with post-treatment recurrence of bacterial vaginosis (BV), clinical factors and vaginal microbiota were examined and analyzed for BV patients who received standard metronidazole therapy. The variables associated with BV recurrence included clinical factors of past BV history, use of intravaginal device, and D7 Nugent score as well as many microbial genera, with Lactobacillus, Enterococcus, Ureaplasma, and Aerococcus being the top contributors. Co-occurrence network analysis showed that whereas overwhelming majority of interbacterial interactions were positive, negative interactions were present and connected mostly to Lactobacillus, Enterococcus, and to a less extent Ureaplasma, suggesting the importance of interbacterial antagonism for treatment outcome. The patients who were cured and recurrent also exhibited clear differences in the species composition of Lactobacillus: although L. iners remained the dominant species at all time points, L. crispatus, L. gasseri, and L. jensenii displayed apparent differences in relative abundance between the cure and recurrent groups. Based on these results, we developed a 5-component panel comprising Enterococcus, L. crispatus, Ureaplasma, Aerococcus, and L. jensenii for predicting recurrence using D7 data and showed that it generated the specificity, sensitivity, and AUC values of 0.80, 0.66, and 0.73 for the discovery cohort and 0.80, 0.67, and 0.69 for the validation cohort. Our findings highlighted key microbial components for BV recurrence and suggested that they could be used to monitor the treatment outcome.

Prognostic Indicators of Recurrence of Bacterial Vaginosis

Following all forms of therapy for bacterial vaginosis (BV), recurrence rates are extremely high. Many diagnostic tests are available that differentiate bacterial vaginosis from other types of vaginal disorders, but none predict recurrence after treatment, nor are any vetted for monitoring ongoing responses to treatment. Our goal was to determine which tests, and at what optimal times, have prognostic value in predicting recurrence. This prospective cohort study monitored 74 highly recurrent BV patients for up to 9 months. Symptomatic BV patients were treated with oral metronidazole and were evaluated at cessation of treatment and monthly. Index tests included Amsel, Nugent, BV Blue, and Affirm VPIII, as well as a quantitative PCR (qPCR)-based test under initial evaluation here. The qPCR-based LbRC ( LactobacillusRelative Composition) assay predicted BV recurrence when performed shortly after oral metronidazole treatment, with both 90% positive predictive values (PPV) and 74% negative predictive values (NPV); the Nugent scores had 93% PPV but poor NPV (57%). No test, at any other visit, was prognostic. The LbRC assay and, to a lesser extent, Nugent tests scored a week after oral metronidiazole predicted recurrence, suggesting that the recurrence in this cohort was predominantly by relapse due to incomplete restoration of eubiosis soon after therapy. This is the first study in an under evaluated population of recurrent BV patients that emphasizes the need for and a pathway to a possible prognostic modality. Given the high recurrence rates of BV, prognostic tests that could influence individualized treatment alternatives are urgently needed.

Interaction of Gardnerella vaginalis and Vaginolysin with the Apical versus Basolateral Face of a Three-Dimensional Model of Vaginal Epithelium

Studies have implicated Gardnerella vaginalis as an important etiological agent in bacterial vaginosis (BV). It produces a cholesterol-dependent cytolysin, vaginolysin (VLY). In this study, we sought to characterize the interaction between vaginal epithelium, G. vaginalis, and VLY using EpiVaginal tissues from MatTek. These tissues are three-dimensional and have distinct apical and basolateral sides, enabling comparison of the effects of G. vaginalis and VLY following exposure to either side. We measured cytotoxicity, cytokine production, and bacterial growth, following apical versus basolateral exposure. G. vaginalis exhibited more-rapid growth in coculture with the tissue model when it was exposed to the apical side. VLY permeabilized cells on the basolateral side of the tissues but failed to permeabilize apical epithelial cells. Cytokine secretion in response to VLY and G. vaginalis also depended on the polarity of exposure. VLY did not cause significant changes in cytokine levels when exposed apically. Apical tissue challenge by G. vaginalis appeared to dampen the inflammatory response, as decreases in granulocyte-macrophage colony-stimulating factor (GM-CSF) (6.6-fold), RANTES (14.8-fold), and interferon gamma inducible protein 10 kDa (IP-10) (53-fold) and an increase in interleukin-1 receptor antagonist (IL-1ra) (5-fold) were observed. In vivo, G. vaginalis normally colonizes the apical face of the vaginal epithelium. Results from this study suggest that while G. vaginalis may grow on the apical face of the vaginal epithelium, its VLY toxin does not target these cells in this model. This phenomenon could have important implications regarding colonization of the vagina by G. vaginalis and may suggest an explanation for the lack of an overt immune response to this organism.

Combined oral contraceptive pill-exposure alone does not reduce the risk of bacterial vaginosis recurrence in a pilot randomised controlled trial

We conducted a pilot open-label randomised controlled trial of combined (oestrogen-progesterone) oral contraceptive pill (COCP)-exposure aimed to examine its effect on BV-recurrence following first-line antibiotics compared to antibiotics alone. Ninety-five women with symptomatic BV were prescribed antibiotic therapy, randomised to COCP-exposure (intervention) or current non-hormonal contraceptive practices (control) and followed monthly for six-months or until BV-recurrence. Modified intention-to-treat methods requiring either ≥1 clinical (primary/Amsel-outcome) or ≥1 microbiological (secondary/Nugent-outcome) BV-recurrence assessment were applied to determine cumulative recurrence rates. Secondary Cox regression analyses assessed factors associated with recurrence in all women. 92/95 women randomised provided baseline requirements. BV-recurrence rates were similar in women randomised to the COCP (primary/Amsel-outcome: 10/100PY, 95%CI: 6,19/100PY) compared to controls (14/100PY, 95%CI: 9, 21/100PY, p = 0.471). In secondary analyses sex with the same pre-treatment regular sexual partner (RSP; Amsel: Adjusted Hazard Ratio [AHR] = 3.13, 95%CI: 1.41, 6.94, p = 0.005; Nugent: AHR = 2.97, 95%CI: 1.49, 5.83, p = 0.002) and BV-history (Amsel: AHR = 3.03, 95%CI: 1.14, 6.28; Nugent: AHR = 2.78, 95%CI: 1.22, 6.33) were associated with increased BV-recurrence. This pilot RCT of COCP-exposure did not improve BV cure but found sex with an RSP and BV-history were associated with recurrence, although impacted by sample size and attrition. These data indicate reinfection from an untreated RSP and persistence of BV-associated bacteria are integral to the pathogenesis of recurrence and may overwhelm potential beneficial effects of hormonal contraception on the vaginal microbiota.

Bacterial vaginosis: An insight into the prevalence, alternative treatments regimen and it's associated resistance patterns

Bacterial Vaginosis (BV) is a complex polymicrobial infection of vagina that shifts the paradigms of vaginal flora from lactobacilli to opportunistic pathogens. BV is catagorized by greyish white discharge, pH greater than 4.5. It results in the preterm labor, abortion, pelvic inflammatory disorders, post cesarean infections. BV is associated with Sexually Transmitted Diseases (STDs) or immune deficiency disorders like Human Immunodeficiency Virus, Human Papilloma Virus, Herpes Simplex Virus 1 and 2, and Neisseria gonorrhoeae. The prevalence rate is about 21.2 million (29.2%) worldwide. BV is more frequent in black females as compared to white females, independent of geographical distribution. Globally, BV is treated with the current recommended antibiotic therapy including Metronidazole and Clindamycin. The recurrence rates are 76% and occur within 06 months of treatment due to antibiotic resistance against pathogenic bacteria and their biofilms. The antibiotic resistance is a global health issue which directs the attentions towards other treatments. One of these is the treatment of sex partners, thus helping to stop the recurrence rates in females. However, this method does not show any positive results. Probiotic therapy is an incorporation of Lactobacilli orally or intravaginally for the recolonization of healthy microbes. This therapy has exhibited promising results but some studies revealed that Probiotic therapy does not control the recurrence rate. The other methods are in trials period and none of them are used clinically or commercially available for the treatment. The thermoplastic polyurethane (TPU) intravaginal rings contain lactic acid and metronidazole showed promising results in trials of BV treatment. The vaginal acidifiers are used as an alternative method to maintain the vaginal pH but the process of douching is a major limitation. The activated charcoal is used to treat BV patients in clinical trials showed decrease in the pH with only 3.1% loss of lactobacilli. Phage therapy is a reemerging field to overcome the bacterial resistance. They are host specific and easier to handle. They can be used naturally, synthetically; phage cocktails and phage-antibiotics combination can be used. Phages show auspicious results for the treatment of bacterial infections as compared to antibiotics as they also treat biofilms. This is one of the promising therapy in future to treat infections with no side effects. Phage therapy can be used in pharmaceuticals according to Food and Drug Administration (FDA) guidelines. Taken together, it is suggested that large funding is required by pharmaceutical sector or government for further investigation of bacteriophages to be used against BV pathogenesis.

Use of the mtrR Gene for Rapid Molecular Diagnosis of Neisseria gonorrhoeae and Identification of the Reduction of Susceptibility to Antibiotics in Endocervical Swabs

BACKGROUND

Neisseria gonorrhoeae is one of the main etiological agents of sexually transmitted diseases. The asymptomatic course of the infection and its resistance to antibiotics can lead to pelvic inflammatory disease and infertility.

OBJECTIVES

We developed a polymerase chain reaction (PCR) test using the methyltetrahydrofolate homocysteine methyltransferase reductase (mtrR) gene to identify N. gonorrhoeae and detect reduced susceptibility to antibiotics.

MATERIAL AND METHODS

We analysed 250 samples of endocervical exudate from infertile women with a negative diagnosis of N. gonorrhoeae. We designed NGmtr primers to detect N. gonorrhoeae and identify the antibiotic-resistant strain.

RESULTS

Of the 250 samples, 60 (24%) tested positive for N. gonorrhoeae using real-time PCR. Our study was validated using the HO primers and the Seeplex STD6 ACE System, with a 100% correlation. Furthermore, the NGmtr primers are specific for N. gonorrhoeae and not for other species. Additionally, the curves generated by real-time PCR differed between wild and variant strains (10.93%). The dissociation temperatures for the wild and variant strains were 86.5 and 89 °C, respectively.

CONCLUSIONS

The NGmtr primers enabled us to identify N. gonorrhoeae strains with or without reduction of susceptibility to antibiotics. Therefore, this work constitutes a tool that will facilitate the diagnosis of this infection for a low cost and improve patient quality of life.

Secnidazole: next-generation antimicrobial agent for bacterial vaginosis treatment

Secnidazole is a next-generation 5-nitroimidazole approved for more than three decades in Europe, Asia, South America and Africa and recently in the USA as a single-dose (2 g) treatment of bacterial vaginosis (BV). Secnidazole is characterized by potent in vitro antimicrobial activity against BV-associated pathogens, as well as prolonged terminal elimination half-life and systemic exposure. These characteristics form the basis of effective and safe treatment of BV with a 2-g single-dose secnidazole regimen, which was recently confirmed in double-blind, placebo-controlled clinical trials conducted in the USA. The option to treat BV with single-dose secnidazole not only cures the primary infection but also may diminish risks of serious sequelae of untreated or undertreated infection.

Prevalence of Bacterial Vaginosis and Its Association with Risk Factors among Nonpregnant Women: A Hospital Based Study

Bacterial vaginosis (BV) is an ecological imbalance of the vaginal microbiota affecting mostly women of reproductive age group. This study was carried out among 160 nonpregnant women registered at the Outpatient Department of Gynaecology/Obstetrics of KIST Medical College Teaching Hospital, Imadol, Lalitpur, Nepal, from November 2014 to May 2015. The aim of the study was to assess the association of the risk factors with BV and analyze the type of bacteria associated with BV. Nugent's scoring method was used for diagnosis of BV in this study. The overall prevalence of BV was 24.4% among symptomatic patients. Douching was statistically related to BV (P = 0.015). Also, BV was significantly associated with consistency (P = 0.0001), odor (P = 0.02), and amount of abnormal vaginal discharge (P = 0.09). Contraceptives users on anatomical sites were found more prone to BV than those who did not use contraceptives on anatomical sites. Pseudomonas spp., Escherichia coli, Acinetobacter spp., Proteus spp., Klebsiella spp., Neisseria gonorrhoeae, Enterobacter spp., Citrobacter spp., Staphylococcus aureus, Coagulase-Negative Staphylococci (CoNS), and Streptococcus agalactiae were associated with BV and out of those Lactobacillus spp. was the predominant organism. The higher prevalence of BV among symptomatic patients indicates interventions should be applied to reduce the incidence of stillbirth, abortion, and sterility.

Microbial Composition Predicts Genital Tract Inflammation and Persistent Bacterial Vaginosis in South African Adolescent Females

Young African females are at an increased risk of HIV acquisition, and genital inflammation or the vaginal microbiome may contribute to this risk. We studied these factors in 168 HIV-negative South African adolescent females aged 16 to 22 years. Unsupervised clustering of 16S rRNA gene sequences revealed three clusters (subtypes), one of which was strongly associated with genital inflammation. In a multivariate model, the microbiome compositional subtype and hormonal contraception were significantly associated with genital inflammation. We identified 40 taxa significantly associated with inflammation, including those reported previously (Prevotella, Sneathia, Aerococcus, Fusobacterium, and Gemella) as well as several novel taxa (including increased frequencies of bacterial vaginosis-associated bacterium 1 [BVAB1], BVAB2, BVAB3, Prevotella amnii, Prevotella pallens, Parvimonas micra, Megasphaera, Gardnerella vaginalis, and Atopobium vaginae and decreased frequencies of Lactobacillus reuteri, Lactobacillus crispatus, Lactobacillus jensenii, and Lactobacillus iners). Women with inflammation-associated microbiomes had significantly higher body mass indices and lower levels of endogenous estradiol and luteinizing hormone. Community functional profiling revealed three distinct vaginal microbiome subtypes, one of which was characterized by extreme genital inflammation and persistent bacterial vaginosis (BV); this subtype could be predicted with high specificity and sensitivity based on the Nugent score (≥9) or BVAB1 abundance. We propose that women with this BVAB1-dominated subtype may have chronic genital inflammation due to persistent BV, which may place them at a particularly high risk for HIV infection.

Sexually transmitted infections: challenges ahead

WHO estimated that nearly 1 million people become infected every day with any of four curable sexually transmitted infections (STIs): chlamydia, gonorrhoea, syphilis, and trichomoniasis. Despite their high global incidence, STIs remain a neglected area of research. In this Commission, we have prioritised five areas that represent particular challenges in STI treatment and control. Chlamydia remains the most commonly diagnosed bacterial STI in high-income countries despite widespread testing recommendations, sensitive and specific non-invasive testing techniques, and cheap effective therapy. We discuss the challenges for chlamydia control and evidence to support a shift from the current focus on infection-based screening to improved management of diagnosed cases and of chlamydial morbidity, such as pelvic inflammatory disease. The emergence and spread of antimicrobial resistance in Neisseria gonorrhoeae is globally recognised. We review current and potential future control and treatment strategies, with a focus on novel antimicrobials. Bacterial vaginosis is the most common vaginal disorder in women, but current treatments are associated with frequent recurrence. Recurrence after treatment might relate to evidence that suggests sexual transmission is integral to the pathogenesis of bacterial vaginosis, which has substantial implications for the development of effective management approaches. STIs disproportionately affect low-income and middle-income countries. We review strategies for case management, focusing on point-of-care tests that hold considerable potential for improving STI control. Lastly, STIs in men who have sex with men have increased since the late 1990s. We discuss the contribution of new biomedical HIV prevention strategies and risk compensation. Overall, this Commission aims to enhance the understanding of some of the key challenges facing the field of STIs, and outlines new approaches to improve the clinical management of STIs and public health.

Current Treatment of Bacterial Vaginosis-Limitations and Need for Innovation

Practitioners and patients alike widely recognize the limitations of current therapeutic approaches to the treatment of bacterial vaginosis (BV). Options remain extremely limited, and our inability to prevent the frequently, often relentless symptomatic recurrences of BV and to reduce serious sequelae such as preterm delivery, remains an acknowledged but unresolved shortcoming. Our incomplete understanding of the pathophysiology of this unique form of vaginal dysbiosis has been a significant impediment to developing optimal treatment and prevention approaches. New drugs have not been forthcoming and are not likely to be available in the immediate future; hence, reliance on the optimal use of available agents has become essential as improvised often unproven regimens are implemented. In this review, we will explore the limitations of currently recommended therapies, with a particular focus on the contribution of reinfection and pathogen persistence to BV recurrence, and the development of interventions that target these mechanisms. Ultimately, to achieve sustained cure and effectiveness against BV-associated sequelae, it is possible that we will need approaches that combine antimicrobials with biofilm-disrupting agents and partner treatments in those at risk of reinfection.

Etiology of bacterial vaginosis and polymicrobial biofilm formation

Microorganisms in nature rarely exist in a planktonic form, but in the form of biofilms. Biofilms have been identified as the cause of many chronic and persistent infections and have been implicated in the etiology of bacterial vaginosis (BV). Bacterial vaginosis is the most common form of vaginal infection in women of reproductive age. Similar to other biofilm infections, BV biofilms protect the BV-related bacteria against antibiotics and cause recurrent BV. In this review, an overview of BV-related bacteria, conceptual models and the stages involved in the polymicrobial BV biofilm formation will be discussed.

Lack of a Pharmacokinetic Interaction Between SYM-1219 Granules Containing 2 Grams of Secnidazole and a Combined Oral Contraceptive in a Phase 1, Randomized, Open-Label Study in Healthy Female Volunteers

INTRODUCTION

Bacterial vaginosis (BV) is a serious infection that is the most common vaginal infection in women of childbearing potential. SYM-1219 is a novel, granule formulation containing 2 g of secnidazole that is being developed as a single, oral dose to treat women with BV. Because many of the women diagnosed with BV use hormonal contraception, the effect of SYM-1219 on the pharmacokinetics (PK) of commonly prescribed oral contraceptive drugs, ethinyl estradiol (EE2), and norethindrone (NET) was evaluated.

METHODS

This two-period, randomized, open-label study examined effects in 54 healthy female subjects. During the first period of the study, each subject received EE2 0.035-mg/NET 1-mg tablets. During the second period of the study, subjects were randomized to receive either EE2 0.035-mg/NET 1-mg tablets with concomitant 2-g SYM-1219 or 2-g SYM-1219 followed by EE2 0.035-mg/NET 1-mg tablets 1 day later. The PK of EE2 and NET were analyzed for 24 h following administration.

RESULTS

Coadministration of SYM-1219 and EE2/NET, either on the same day or 1 day apart, had no clinically relevant effects on the bioavailability of EE2 or NET. The combined use of SYM-1219 with EE2/NET was well tolerated. Taken together, these results indicate that contraceptive efficacy should be maintained during coadministration of SYM-1219 and EE2/NET.

CONCLUSION

SYM-1219 is a valuable single-dose treatment option for women with BV that will not interfere with combined oral contraceptive methods.

FUNDING

Symbiomix Therapeutics.

The Human Microbiome during Bacterial Vaginosis

Bacterial vaginosis (BV) is the most commonly reported microbiological syndrome among women of childbearing age. BV is characterized by a shift in the vaginal flora from the dominant Lactobacillus to a polymicrobial flora. BV has been associated with a wide array of health issues, including preterm births, pelvic inflammatory disease, increased susceptibility to HIV infection, and other chronic health problems. A number of potential microbial pathogens, singly and in combinations, have been implicated in the disease process. The list of possible agents continues to expand and includes members of a number of genera, including Gardnerella, Atopobium, Prevotella, Peptostreptococcus, Mobiluncus, Sneathia, Leptotrichia, Mycoplasma, and BV-associated bacterium 1 (BVAB1) to BVAB3. Efforts to characterize BV using epidemiological, microscopic, microbiological culture, and sequenced-based methods have all failed to reveal an etiology that can be consistently documented in all women with BV. A careful analysis of the available data suggests that what we term BV is, in fact, a set of common clinical signs and symptoms that can be provoked by a plethora of bacterial species with proinflammatory characteristics, coupled to an immune response driven by variability in host immune function.

Prevalence of O25b-ST131 clone among Escherichia coli strains producing CTX-M-15, CTX-M-14 and CTX-M-92 β-lactamases

BACKGROUND

Dissemination of multidrug-resistant Escherichia coli is closely associated with the worldwide spread of a single clone ST131, which is the main cause of urinary tract and bloodstream infections in patients from nursing homes and immunocompromised patients. The aim of our study was to determine the prevalence of ST131 clone and the replicons involved in the spread of bla_CTX-M genes among O25b-ST131 CTX-M-producing E. coli isolates in Lithuania.

METHODS

The strains included in this study were screened for CTX-M β-lactamase-encoding genes, phylogenetic groups and ST131 clone by PCR. Bacterial conjugation was performed to identify plasmid replicon types responsible for bla_CTX-M genes dissemination.

RESULTS

A total of 158 E. coli clinical non-duplicate ESBL isolates were analyzed. Nearly half (n = 67, 42.4%) of the investigated E. coli isolates belonged to phylogenetic group B2. The isolates producing CTX-M-92 β-lactamases were identified to be the ST131 clone more frequently than the non-ST131 clone (11.5% vs. 3.1%, p = .035). The CTX-M-15 isolates were identified as ST131 isolates less frequently than non-ST131 isolates (50.8% vs. 71.1%; p = .015). The ST131 clone isolates contained type L/M and A/C replicons; a fused FII/FIB replicon was found in four isolates (23.5%). Type HI1 replicon was identified in ST131 E. coli isolates producing CTX-M-15 β-lactamases.

CONCLUSIONS

This study demonstrates the predominance of the ST131 clone among CTX-M β-lactamase-producing E. coli isolates. Dissemination of bla_CTX-M genes in ST131 strains can be linked not only to highly adapted IncF plasmids such as FII/FIB and FII, but also to plasmid replicon types A/C, L/M and HI1.

Utilization of molecular methods to identify prognostic markers for recurrent bacterial vaginosis

BACKGROUND

Recurrent bacterial vaginosis (BV) after antimicrobial therapy is a major problem, affecting >50% of patients within 1 year. The objective of this study was to determine if prospective identification of patients at risk for recurrence using molecular methods is feasible.

METHODS

Women were evaluated for BV by Amsel criteria and Nugent score. Vaginal specimens were analyzed using a panel of quantitative real-time polymerase chain reactions (qPCRs) at three times: pre-treatment, 7-10days post-treatment and 40-45days post-treatment. The PCRs quantified DNA of the following organisms: Gardnerella vaginalis; Atopobium vaginae; Bacterial Vaginosis-Associated Bacteria-1 (BVAB1), -2 (BVAB2) and -3 (BVAB3); Leptotrichia/Sneathia; Megasphaera Phylotypes 1 and 2; and Lactobacillus spp. (L. crispatus, L. gasseri, L. iners and L. jensenii).

RESULTS

Out of 84 women diagnosed with BV (Amsel ≥3 and Nugent ≥4), 77 (91.7%) were successfully treated after 7-10days (asymptomatic and Amsel of either 0 or 1 with elevated vaginal pH and Nugent ≤6). Of these 77 women, 46 (59.7%) remained cured after 40-45days and 31 (40.3%) developed recurrent BV. In univariate analysis, we found that women who would have recurrent BV during the study had greater concentrations of Megasphaera Phylotype 2 (P=0.001) and BVAB2 (P=0.015) at initial diagnosis and greater vaginal pH (P=0.030), higher Nugent score (P=0.043) and a greater concentration of G. vaginalis (P=0.012) post-treatment, when compared to women who were cured during the study. These differences largely remained when cure was defined as Nugent ≤3 or when only women treated with intravaginal metronidazole were evaluated.

CONCLUSION

Molecular analysis of BV is a useful adjunct to clinical and microscopic analysis to prospectively identify patients at high risk for recurrent BV.

Relationship of Specific Bacteria in the Cervical and Vaginal Microbiotas With Cervicitis

BACKGROUND

Cervicitis is an inflammatory condition of the cervix associated with upper genital tract infection and reproductive complications. Although cervicitis can be caused by several known pathogens, the etiology frequently remains obscure. Here we investigate vaginal bacteria associated with bacterial vaginosis as potential causes of cervicitis.

METHODS

Associations between vaginal bacteria and cervicitis were assessed in a retrospective case-control study of women attending a Seattle sexually transmitted disease clinic. Individual bacterial species were detected using 2 molecular methods: quantitative polymerase chain reaction (qPCR) and broad-range 16S rRNA gene PCR with pyrosequencing. The primary finding from this initial study was evaluated using qPCR in a second cohort of Kenyan women.

RESULTS

The presence of Mageeibacillus indolicus, formerly BVAB3, in the cervix was associated with cervicitis, whereas the presence of Lactobacillus jensenii was inversely associated. Quantities of these bacteria did not differ between cervicitis cases and controls, although in a model inclusive of presence and abundance, M. indolicus remained significantly associated with cervicitis after adjustment for other cervicitis-causing pathogens. M. indolicus was not associated with cervicitis in our study of Kenyan women, possibly due to differences in the clinical definition of cervicitis.

CONCLUSIONS

Colonization of the endocervix with M. indolicus may contribute to the clinical manifestations of cervicitis, but further study is needed to determine whether this finding is repeatable and applicable to diverse groups of women. Colonization of the cervix with L. jensenii could be a marker of health, perhaps reducing inflammation or inhibiting pathogenic infection.

The bacterial etiology of preterm birth

Preterm birth is the leading cause of infant morbidity and mortality. Very preterm births, those occurring before 32 completed weeks of gestation, are associated with the greatest risks. The leading cause of very preterm birth is intrauterine infection, which can lead to an inflammatory response that triggers labor or preterm premature rupture of membranes. How bacteria invade the uterine cavity, which is normally a sterile environment, and the reasons why different species vary in their capacity to induce inflammation and preterm birth are still incompletely understood. However, advanced techniques that circumvent the need for cultivating bacteria, deep sequence analysis that allows for the comprehensive characterization of the microbiome of a given body site and detection of low-prevalence species, and transcriptomics and metabolomics approaches that shed light on the host response to bacterial invasion are all providing a more complete picture of the progression from vaginal colonization to uterine invasion to preterm labor and preterm birth.