Extended antimicrobial treatment of bacterial vaginosis combined with human lactobacilli to find the best treatment and minimize the risk of relapses

Pilot Study on Next-Generation Sequencing Analysis of Vaginal Microbiota in Clinically Infertile Patients Treated with Probiotics

Background: In this investigation, we aimed to understand the influence of oral probiotic supplementation on the vaginal microbiota of women preparing for assisted reproductive technology (ART) procedures. Given the importance of a healthy microbiome for reproductive success, this study sought to explore how probiotics might alter the bacterial composition in the vaginal environment. Methods: We recruited a cohort of 30 women, averaging 37 years of age (ranging from 31 to 43 years), who were scheduled to undergo ART. Using 16S ribosomal RNA (rRNA) sequencing, we meticulously analyzed the vaginal microbiota composition before and after the administration of oral probiotic supplements. Results: Our analysis identified 17 distinct microorganisms, including 8 species of Lactobacillus. Following probiotic supplementation, we observed subtle yet notable changes in the vaginal microbiota of some participants. Specifically, there was a decrease in Gardnerella abundance by approximately 20%, and increases in Lactobacillus and Bifidobacterium by 10% and 15%, respectively. Additionally, we noted a significant reduction in the Firmicutes/Bacteroidetes (F/B) ratio in the probiotic group, indicating potential shifts in the overall bacterial composition. Conclusions: These preliminary findings suggest that oral probiotic supplementation can induce significant changes in the vaginal microbiota of middle-aged women undergoing ART, potentially improving their overall bacterial profile. Future studies should consider a larger sample size and a narrower age range to validate these results. Investigating factors related to female hormone production could also provide deeper insights. Understanding the effects of probiotics on the vaginal microbiota in patients with ovarian aging may lead to personalized interventions and better reproductive outcomes.

Antibiotics therapy combined with probiotics administered intravaginally for the treatment of bacterial vaginosis: A systematic review and meta-analysis

The objective was to examine the pooled effects of antibiotic-probiotic combinations by examining the cure rate and recurrence rate for bacterial vaginosis (BV). A systematic literature search was conducted from electronic databases. All parallel randomized controlled trials (RCTs) that focused on the effects of antibiotics combined with intravaginal probiotics were included. Cure rate and recurrence rate were the primary and secondary outcomes to be analyzed. Meta-analysis was conducted following the Cochrane handbook for Systematic Reviews of Interventions. As a result, of 923 studies identified, 11 articles involving 1,493 BV patients met the inclusion criteria and nine were available for meta-analysis. A meta-analysis of two studies evaluated the recurrence rate 12-16 weeks after treatment. Results showed a statistically significant difference favoring the antibiotics plus probiotics group vs the antibiotics plus placebo group (relative risk 0.62, 95% confidence interval [CI]: 0.45-0.85). The narrative review in one study indicated that the cure rate was higher in the antibiotics plus probiotics group, giving a significant HR ratio of 0.73 (95% CI 0.54-0.98) (p = 0.042). In conclusion, vaginal application of Lactobacillus in combination with antibiotics for the treatment of BV could be a promising method for both reducing the recurrence rate and relieving symptoms of BV.

Lactobacilli and Their Probiotic Effects in the Vagina of Reproductive Age Women

In the present narrative review, the probiotic effects of vaginal Lactobacillus spp. are described in detail, covering the importance of the differential production of lactic acid, the lactic acid D/L isoforms, the questionable in vivo effect of hydrogen peroxide, as well as bacteriocins and other core proteins produced by vaginal Lactobacillus spp. Moreover, the microbe–host interaction is explained with emphasis on the vaginal mucosa. To understand the crucial role of Lactobacillus spp. dominance in the vaginal microbiota, different dysbiotic states of the vagina are explained including bacterial vaginosis and aerobic vaginitis. Finally, this review takes on the therapeutic aspect of live lactobacilli in the context of bacterial vaginosis. Until recently, there was very low-quality evidence to suggest that any probiotic might aid in reducing vaginal infections or dysbiosis. Therefore, clinical usage or over the counter usage of probiotics was not recommended. However, recent progress has been made, moving from probiotics that are typically regulated as food supplements to so-called live biotherapeutic products that are regulated as medical drugs. Thus, recently, a phase 2b trial using a Lactobacillus crispatus strain as a therapeutic add-on to standard metronidazole showed significant reduction in the recurrence of bacterial vaginosis by 12 weeks compared to placebo. This may constitute evidence for a brighter future where the therapeutic use of lactobacilli can be harnessed to improve women’s health.

Effectivity and efficacy probiotics for Bacterial Vaginosis treatments: Meta-analysis

Introduction

Bacterial Vaginosis (BV) is the most common cause of vaginal discharge. However, in some cases, side effects and resistance rates have been reported when antibiotics are administered. This problem has prompted several investigations on the administration of probiotics as an adjunct therapy to treat this infection.

Objection

This study aims to conduct a meta-analysis based on evidence to determine the efficacy and safety of probiotic and antibiotic treatments.

Methods

The meta-analysis was performed using PRISMA guidelines. The literature review was conducted in December 2020 using PubMed, Science Direct, Cochrane Library, and RevMan V.5.3.

Result

The results showed a high and significant cure rate from the analysis of 1006 and 528 samples of probiotics and non-probiotics or control in 16 studies. The recurrence rate was statistically significant with probiotic treatment. Furthermore, neither procedures nor therapy failure showed a significantly lower adverse event rate than the control group.

Conclusion

Probiotic shows better results compared to the control group. However, both have the same occurrence of adverse event.

Formulation and Optimization of Metronidazole and Lactobacillus spp. Layered Suppositories via a Three-Variable, Five-Level Central Composite Design for the Management of Bacterial Vaginosis

Bacterial vaginosis, a polymicrobial clinical syndrome characterized by a shift in healthy vaginal microbiota due to bacterial colonization, is characterized by high recurrence rates after conventional treatment with an antimicrobial agent. This has necessitated the need to develop a formulation that has the potential to ensure Lactobacilli viability and bacterial clearance. This study seeks to develop and optimize a layered suppository using a five-level central composite design to ensure optimized metronidazole release and lactic acid viability. Layered suppositories were formulated using the fusion method using polyethylene glycol blend 1500/4000 and Ovucire^® as suppository bases. Lactobacillus fermentum was incorporated in the molten mass before molding the solid body suppositories into the cavity of hollow-type suppositories and sealing the molten excipients. Artificial neural network model predictions for product optimization showed high predictive capacity, closely resembling experimental observations. The highest disintegration time recorded was 12.76 ± 0.37 min, with the optimized formulations showing lower times of 5.93 ± 0.98 min and an average weight of 1.17 ± 0.07 g. Histopathological observations determined high compatibility of suppositories with vaginal cells with no distortion or wearing of the vagina epithelium. This optimized formulation provides a safe and promising alternative to conventional suppositories in the treatment and prevention of the recurrence of bacterial vaginosis.

Cervicovaginal microbiota isolated from healthy women exhibit probiotic properties and antimicrobial activity against pathogens isolated from cervical cancer patients

Abnormal cervicovaginal microbiota play an important role in HPV persistence and progression to cervical cancer. The present study aimed at isolating and identifying potential probiotics from vaginal swabs of healthy women and evaluating their activity against vaginal pathogens isolated from cervical cancer patients. Based on probiotic, acid-bile tolerance and antimicrobial properties, 13 lactic acid bacteria (LAB) from the healthy group were identified by MALDI TOF MS (Matrix Assisted Laser Desorption and Ionisation, Time Of Flight Mass Spectrometry). Among these, four strains, Lactobacillus gasseri P36Mops, Limosilactobacillus fermentum P37Mws, Lactobacillus delbrueckii P31Mcs and Enterococcus faecium P26Mcm, exhibited significant antimicrobial activity against 8 vaginal pathogens (Staphylococcus haemolyticus P41Tcs, Escherichia coli P30Tcs, E. coli P79Bcm, Enterococus faecalis P29Mops, E. faecalis P50Tws, E. faecalis P68Tcb, S. haemolyticus P48Bcb and S. haemolyticus P58Bcb) isolated from precancerous and cervical cancer patients. 16S rRNA sequencing of four potential probiotics revealed congruency with the MALDI-TOF MS identification and phylogenetic analysis showed genetic relationship with previously reported LAB strains. The selected LAB showed strain specific hydrophobicity (35.88-56.70%), auto-aggregation (35.26-61.39%) and antibiotic susceptibility. Interestingly, L. gasseri P36Mops was resistant to five standard antibiotics routinely used against urogenital or vaginal infections. LCMS (Liquid Chromatography Mass Spectrometry) analyses of the CFS (cell-free supernatant) of the four potential probiotics revealed the presence of metabolites such as N-(1-deoxy-1-fructosyl)valine, hygroline, acetoxy-2-hydroxy-16-heptadecen-4-one, avocadyne 4-acetate, avocadyne 2-acetate, taraxinic acid glucosyl ester, 6-hydroxypentadecanedioic acid, with reported antimicrobial activity. The overall data suggest the bio-therapeutic potential of the identified vaginal probiotics against cervical cancer-associated pathogens.

The vaginal microbiome following orally administered probiotic

INTRODUCTION

Here we present a longitudinal shotgun sequencing metagenomics study of 16 healthy, Danish women in the reproductive age. The aim of the study was to investigate whether lactobacilli, orally consumed, had any impact on the vaginal microbiome and its functional potential.

MATERIALS AND METHODS

The 16 women aged 19-45 years were recruited from Copenhagen, Denmark. One baseline vaginal sample (day 0) and two study samples (day 25-30 and day 55-60, respectively) were sampled. The vaginal samples were analyzed by shotgun metagenomics.

RESULTS

We detected 26 species in the vaginal microbiota of the 16 women, of which six belonged to the Lactobacillus genus. We observed three vaginal microbiome clusters mainly dominated by Gardnerella vaginalis, Lactobacillus iners or Lactobacillus crispatus. The oral probiotic had no detectable effect on either the composition or the functional potential of the vaginal microbiota.

DISCUSSION

Most of the study subjects (11 out of 16 women) exhibited only minor changes in the vaginal microbiome during the treatment with probiotics. Any compositional changes could not be associated to the probiotic treatment. Future studies may benefit from an increased number of participants, and administration of the probiotics during conditions with bacterial imbalance (e.g. during/after antibiotic treatment) or the use of different Lactobacillus spp. known to colonize the vagina.

Comparative Effectiveness of Treatments for Bacterial Vaginosis: A Network Meta-Analysis

Bacterial vaginosis (BV) is a common vaginal dysbiosis in women of reproductive age. However, the cure rate for BV varies considerably and many women experience a relapse after the initial treatment. The present meta-analysis aimed to evaluate the clinical cure rates (CCRs) in randomized controlled trials (RCTs) through different therapies and administration routes. This meta-analysis included a final set of 25 eligible studies with a total of 57 RCTs and compared the effectiveness of BV treatments among non-pregnant and pregnant women. The initial range of CCRs varied greatly from 46.75% to 96.20% and the final pooled CCR was 75.5% (CI: 69.4-80.8) using the random model. The heterogeneity indices were Q = 418.91, I2 = 94.27%, and τ = 0.7498 (p < 0.0001). No publication bias was observed according to Funnel plot symmetry and Egger's linear regression test (p = 0.1097). To evaluate different variables, sub-group analysis, meta-regressions, and network meta-analysis were also realized. The highest P-scores in CCR were obtained by: (1) a combined therapy with local probiotic treatment and application of antibiotics by both administration route (oral clindamycin and local 5-nitroimidazole; P-score = 0.92); (2) a combined therapy with oral administration of 5-nitroimidazole and probiotic treatment (P-score = 0.82); (3) and a combined therapy with local administration of 5-nitroimidazole and oral probiotic treatment (P-score = 0.68). A clear-cut decision of the best BV treatment was not possible due to the heterogeneity of outcomes reported in the trials, indicating the necessity for a better characterization of RCTs. Finally, combined therapies suggested the reduction of the optimal concentration of antibiotics, and double phase treatments of antibiotics indicated an increment of CCRs in BV.

The Female Vaginal Microbiome in Health and Bacterial Vaginosis

The vaginal microbiome is an intricate and dynamic microecosystem that constantly undergoes fluctuations during the female menstrual cycle and the woman's entire life. A healthy vaginal microbiome is dominated by Lactobacillus which produce various antimicrobial compounds. Bacterial vaginosis (BV) is characterized by the loss or sharp decline in the total number of Lactobacillus and a corresponding marked increase in the concentration of anaerobic microbes. BV is a highly prevalent disorder of the vaginal microbiota among women of reproductive age globally. BV is confirmed to be associated with adverse gynecologic and obstetric outcomes, such as sexually transmitted infections, pelvic inflammatory disease, and preterm birth. Gardnerella vaginalis is the most common microorganism identified from BV. It is the predominant microbe in polymicrobial biofilms that could shelter G. vaginalis and other BV-associated microbes from adverse host environments. Many efforts have been made to increase our understanding of the vaginal microbiome in health and BV. Thus, improved novel and accurate diagnosis and therapeutic strategies for BV have been developed. This review covers the features of vaginal microbiome, BV, BV-associated diseases, and various strategies of diagnosis and treatment of BV, with an emphasis on recent research progresses.

Probiotics in Cosmetic and Personal Care Products: Trends and Challenges

Probiotics, defined as "live microorganisms that, when administered in adequate amounts, confer a health benefit on the host," are becoming increasingly popular and marketable. However, too many of the products currently labelled as probiotics fail to comply with the defining characteristics. In recent years, the cosmetic industry has increased the number of products classified as probiotics. While there are several potential applications for probiotics in personal care products, specifically for oral, skin, and intimate care, proper regulation of the labelling and marketing standards is still required to guarantee that consumers are indeed purchasing a probiotic product. This review explores the current market, regulatory aspects, and potential applications of probiotics in the personal care industry.

Lactobacilli Expressing Broadly Neutralizing Nanobodies against HIV-1 as Potential Vectors for HIV-1 Prophylaxis?

In the absence of an active prophylactic vaccine against HIV-1, passively administered, broadly neutralizing antibodies (bnAbs) identified in some chronically infected persons were shown to prevent HIV-1 infection in animal models. However, passive administration of bnAbs may not be suited to prevent sexual HIV-1 transmission in high-risk cohorts, as a continuous high level of active bnAbs may be difficult to achieve at the primary site of sexual transmission, the human vagina with its acidic pH. Therefore, we used Lactobacillus, a natural commensal in the healthy vaginal microbiome, to express bn nanobodies (VHH) against HIV-1 that we reported previously. After demonstrating that recombinant VHHA6 expressed in E. coli was able to protect humanized mice from mucosal infection by HIV-1Bal, we expressed VHHA6 in a soluble or in a cell-wall-anchored form in Lactobacillus rhamnosus DSM14870. This strain is already clinically applied for treatment of bacterial vaginosis. Both forms of VHHA6 neutralized a set of primary epidemiologically relevant HIV-1 strains in vitro. Furthermore, VHHA6 was still active at an acidic pH. Thus, lactobacilli expressing bn VHH potentially represent an attractive vector for the passive immunization of women in cohorts at high risk of HIV-1 transmission.

Vaginal microbiota and the potential of Lactobacillus derivatives in maintaining vaginal health

Human vagina is colonised by a diverse array of microorganisms that make up the normal microbiota and mycobiota. Lactobacillus is the most frequently isolated microorganism from the healthy human vagina, this includes Lactobacillus crispatus, Lactobacillus gasseri, Lactobacillus iners, and Lactobacillus jensenii. These vaginal lactobacilli have been touted to prevent invasion of pathogens by keeping their population in check. However, the disruption of vaginal ecosystem contributes to the overgrowth of pathogens which causes complicated vaginal infections such as bacterial vaginosis (BV), sexually transmitted infections (STIs), and vulvovaginal candidiasis (VVC). Predisposing factors such as menses, pregnancy, sexual practice, uncontrolled usage of antibiotics, and vaginal douching can alter the microbial community. Therefore, the composition of vaginal microbiota serves an important role in determining vagina health. Owing to their Generally Recognised as Safe (GRAS) status, lactobacilli have been widely utilised as one of the alternatives besides conventional antimicrobial treatment against vaginal pathogens for the prevention of chronic vaginitis and the restoration of vaginal ecosystem. In addition, the effectiveness of Lactobacillus as prophylaxis has also been well-founded in long-term administration. This review aimed to highlight the beneficial effects of lactobacilli derivatives (i.e. surface-active molecules) with anti-biofilm, antioxidant, pathogen-inhibition, and immunomodulation activities in developing remedies for vaginal infections. We also discuss the current challenges in the implementation of the use of lactobacilli derivatives in promotion of human health. In the current review, we intend to provide insights for the development of lactobacilli derivatives as a complementary or alternative medicine to conventional probiotic therapy in vaginal health.

Gardnerella and vaginal health: the truth is out there

The human vagina is a dynamic ecosystem in which homeostasis depends on mutually beneficial interactions between the host and their microorganisms. However, the vaginal ecosystem can be thrown off balance by a wide variety of factors. Bacterial vaginosis (BV) is the most common vaginal infection in women of childbearing age but its etiology is not yet fully understood, with different controversial theories being raised over the years. What is generally accepted is that BV is often characterized by a shift in the composition of the normal vaginal microbiota, from a Lactobacillus species dominated microbiota to a mixture of anaerobic and facultative anaerobic bacteria. During BV, a polymicrobial biofilm develops in the vaginal microenvironment, being mainly composed of Gardnerella species. The interactions between vaginal microorganisms are thought to play a pivotal role in the shift from health to disease and might also increase the risk of sexually transmitted infections acquisition. Here, we review the current knowledge regarding the specific interactions that occur in the vaginal niche and discuss mechanisms by which these interactions might be mediated. Furthermore, we discuss the importance of novel strategies to fight chronic vaginal infections.

An exploratory pilot study evaluating the supplementation of standard antibiotic therapy with probiotic lactobacilli in south African women with bacterial vaginosis

Background

To reduce acquisition and relapse of bacterial vaginosis (BV), lactobacilli must be maintained in the vaginal microbiome. Probiotic lactobacilli may aid this purpose. We investigated whether vaginal probiotics (containing Lactobacillus rhamnosus DSM 14870 and Lactobacillus gasseri DSM 14869) would result in vaginal colonisation with lactobacilli in women with and without BV.

Methods

This prospective, partially randomised, exploratory pilot study was conducted in Soweto, South Africa. Thirty-nine sexually-active, HIV negative women were enrolled from October 2014 to May 2016 into three arms. Women who did not have BV (Group 1, n = 13) self-administered probiotic capsules vaginally once daily for 30 days, then once a week until Day 190. Women diagnosed with BV were randomized into Group 2 (n = 12) or Group 3 (n = 14) and treated with the triple oral antibiotic combination for vaginal discharge syndrome per South African guidelines (cefixime 400 mg stat, doxycycline 100 mg BD for 7 days and metronidazole 2 g stat). Immediately after antibiotic treatment, women in Group 2 self-administered probiotic capsules vaginally once daily for 30 days then vaginally once a week until Day 190. Women in Group 3 were not given lactobacilli.

Results

During the study, L. rhamnosus DSM 14870 or L. gasseri DSM 14869, were isolated in 5/13 (38.5%) women in Group 1 compared to 10/12 (83.3%) women in Group 2 (p = 0.041). The 1-month and 6-month BV cure rates were similar (P >  0.05) between Group 2 (42 and 25%) compared to Group 3 (36 and 25%). In Group 2, no correlation was observed between the frequency of isolation of the two Lactobacillus strains and the 1-month or 6-month cure rate.

Conclusions

Supplementation with vaginal probiotic capsules resulted in colonisation of the vagina by the Lactobacillus strains (L. rhamnosus DSM 14870 and L. gasseri DSM 14869) contained in the capsules. We observed low initial cure rates of BV after a stat dose of metronidazole and that the probiotic did not improve BV cure rates or alleviate recurrence which could be due to treatment failure or very limited power of the study.

Trial registration

Registered at the Pan African Clinical Trial Registry (www.pactr.org) on April 13, 2018 (retrospectively registered). Trial identification number: PACTR201804003327269.

Electronic supplementary material

The online version of this article (10.1186/s12879-019-4425-1) contains supplementary material, which is available to authorized users.

Putative Adhesion Factors in Vaginal Lactobacillus gasseri DSM 14869: Functional Characterization

Lactobacilli play an important role in the maintenance of a healthy vaginal microbiota, and some select species are widely used as probiotics. Vaginal isolates of Lactobacillus gasseri DSM 14869 and Lactobacillus rhamnosus DSM 14870 were previously selected to develop the probiotic EcoVag capsules and showed therapeutic effects in women with bacterial vaginosis (BV). However, the molecular mechanisms involved in their probiotic activity are largely unknown. In this study, we identified three cell surface molecules in L. gasseri DSM 14869 that promote adhesion to vaginal epithelial cells (VEC) by constructing dedicated knockout mutants, including exopolysaccharides (EPSs), a protein containing MucBP-like domains (N506_1778), and a putative novel adhesin (N506_1709) with rib/alpha-like domain repeats. EPS knockout mutants revealed 20-fold and 14-fold increases in adhesion to Caco-2 and HeLa cells, respectively, compared with wild type, while the adhesion to VEC was reduced 30% by the mutation, suggesting that EPSs might mediate tissue tropism for vaginal cells. A significant decrease in adhesion to Caco-2 cells, HeLa cells, and VEC was observed in the N506_1778 knockout mutant. The N506_1709 mutant showed no significant difference for the adhesion to Caco-2 and HeLa cells compared with wild type (WT); in contrast, the adhesion to VEC revealed a significant decrease (42%), suggesting that N506_1709 might mediate specific binding to stratified squamous epithelial cells, and this putative novel adhesin was annotated as Lactobacillus vaginal epithelium adhesin (LVEA). Thus, we have discovered an important role for EPSs and a novel adhesin, LVEA, in the adhesive capacity of a vaginal probiotic Lactobacillus strain.IMPORTANCE Lactobacilli are known to contribute to the maintenance of a healthy vaginal microbiota and some are selected as probiotics for the prevention or treatment of urogenital diseases, such as bacterial vaginosis. However, the molecular mechanisms for these health-promoting effects are not fully understood. Here, we functionally identified three cell surface factors of a Lactobacillus gasseri strain potentially involved in its adhesion to vaginal epithelial cells, including exopolysaccharides (EPSs) and two sortase-dependent proteins (N506_1778 and N506_1709). We could demonstrate the tissue-specific adhesion of EPSs to vaginal cells and that N506_1709 might be a novel adhesin specifically mediating bacterial binding to stratified squamous epithelial cells. The results provide important new information on the molecular mechanisms of vaginal Lactobacillus spp. adhesion.

Community ecology as a framework for human microbiome research

The field of human microbiome research has revealed the intimate co-association of humans with diverse communities of microbes in various habitats in the human body, and the necessity of these microbes for the maintenance of human health. Microbial heterogeneity between humans and across spatial and temporal gradients requires multidimensional datasets and a unifying set of theories and statistical tools to analyze the human microbiome and fully realize the potential of this field. Here we consider the utility of community ecology as a framework for the interrogation and interpretation of the human microbiome.

Forty-five-year evolution of probiotic therapy

In the past forty-five years, the field of probiotics has grown from a handful of laboratory studies and clinical ideas into a legitimate research and translational entity conferring multiple benefits to humans around the world. This has been founded upon three principles: (i) the need for alterna-tives to drugs that either have sub-optimal efficacy or severe adverse effects; (ii) a growing interest in natural products and microbes, in particular cata-lyzed by studies showing the extent of microbes within humans and on our planet; and (iii) evidence on the genetics and metabolic properties of probi-otic strains, and clinical studies showing their effectiveness. While some man-ufacturers have sadly taken advantage of the market growth to sell supple-ments and foods they term probiotic, without the necessary human study evidence, there are more and more companies basing their formulations on science. Adherence to the definition of what constitutes a probiotic, conclu-sions based on tested products not generalizations of the whole field, and applications emanating from microbiome research identifying new strains that provide benefits, will make the next forty-five years significantly changed approaches to health management. Exciting applications will emerge for car-diovascular, urogenital, respiratory, brain, digestive and skin health, detoxifi-cation, as well as usage across the world's ecosystems.

Cross-Domain and Viral Interactions in the Microbiome

The importance of the microbiome to human health is increasingly recognized and has become a major focus of recent research. However, much of the work has focused on a few aspects, particularly the bacterial component of the microbiome, most frequently in the gastrointestinal tract. Yet humans and other animals can be colonized by a wide array of organisms spanning all domains of life, including bacteria and archaea, unicellular eukaryotes such as fungi, multicellular eukaryotes such as helminths, and viruses. As they share the same host niches, they can compete with, synergize with, and antagonize each other, with potential impacts on their host. Here, we discuss these major groups making up the human microbiome, with a focus on how they interact with each other and their multicellular host.

Bacterial vaginosis: A practical review

Bacterial vaginosis is a common vaginal infection that causes discharge, odor, and irritation. It can predispose women to sexually transmitted infections (STIs) including HIV. Recurrent bacterial vaginosis may require prolonged treatment to return the vaginal flora to a normal predominately lactobacilli-dominated environment.

Intrinsic and extrinsic carbohydrates in the vagina: A short review on vaginal glycogen

The reasons for (i) the presence and (ii) mechanisms of utilisation of glycogen by the lactic acid bacteria in the human vaginal tract are not well understood. It is probable that the vaginal epithelia produce both glycogen and α-amylase where the enzyme depolymerises the polysaccharide within the vagina itself. Only these depolymerised residues are then utilised for growth by the lactic acid bacteria. The lactic acid bacteria cannot metabolise the glycogen directly due to their incapacity to produce the α-amylase enzyme. These bacteria may, however, metabolise exogenous carbohydrates (such as prebiotics) selectively for growth effectively. These carbohydrate utilisation issues within the vagina are considered in this short review.

Treatment of Abnormal Vaginal Microbiota before Frozen Embryo Transfer: Case-Report and Minireview to Discuss the Longitudinal Treatment Efficacy of Oral Clindamycin

Abnormal vaginal microbiota (AVM) or bacterial vaginosis (BV) might negatively impact reproductive outcomes of in vitro fertilization (IVF). However, before randomized controlled trials are initiated to investigate cause and effect, it is necessary to establish the optimal treatment for AVM. Metronidazole seems ineffective to treat the biofilm in AVM; thus, clindamycin could be suggested as a relevant antibiotic agent for future intervention based studies. In the present case report, we present the first longitudinal follow-up of the vaginal microbiota with molecular methods during and after oral clindamycin treatment. Furthermore, we review the recent literature with the aim to discuss the optimal AVM treatment in a fertility setting. The patient was 40 years old suffering from unexplained secondary infertility. Prior to the present transfer cycle, she had had two failed IVF cycles. The tentative explanation of failed treatment was age-related aneuploidy. However, the patient asked for AVM diagnosis and she was subsequently diagnosed and treated successfully. Unfortunately, the patient did not achieve pregnancy after clindamycin treatment and two subsequent frozen embryo transfer cycles. Taken together, we report an excellent AVM treatment efficacy both short-term and long-term following oral clindamycin treatment. We discuss the potential impact on the vaginal microbiota of co-treatment with estrogen patches in the stimulated frozen embryo transfer cycle. Furthermore, we discuss future aspects of AVM treatment such as the potential impact of estrogen and live biotherapeutic products to positively modulate the microbiota of the reproductive tract.

Bacterial biota of women with bacterial vaginosis treated with lactoferrin: an open prospective randomized trial

Background: Bacterial vaginosis is the most frequent condition associated to the vaginal microbiota imbalance, affecting about the 40-50% of women in the world. Even if antibiotics are effcetive for bacterial vaginosis treatment a long-term recurrence rates, higher than 70%, is recorded. Lactoferrin is an iron-binding glycoprotein with bacteriostatic and bactericidal properties. It owns the ability to protect the host against infection, by binding and regulating the iron needed for the bacterial proliferation. Objective: The present study was an open prospective randomized trial (registration no. SHI-EVE-2014.01) aimed at characterizing the bacterial biota of women affected by bacterial vaginosis (BV) and assessing the effects of two different lactoferrin concentrations (100 mg and 200 mg vaginal pessaries) on the composition and dynamics of the vaginal bacterial biota. Design: Sixty women with BV were recruited and randomized into two groups to receive lactoferrin pessaries for 10 days. Clinical evaluation was based on Amsel criteria and Nugent scores. Culture-dependent methods and Ion Torrent PGM sequencing of the 16S rRNA gene were applied to study in depth the overall structure of the vaginal bacterial biota and its dynamics during the treatment. Results: Vaginal lactoferrin administration modified the vaginal microbiota composition in patients with BV. During treatment, both 100 mg and 200 mg lactoferrin vaginal pessaries significantly decreased the occurrence of bacteria associated with BV, such as Gardnerella, Prevotella, and Lachnospira, and increased the occurrence of Lactobacillus species. The bacterial biota balance was maintained up to 2 weeks after treatment only in women treated with 200 mg lactoferrin pessaries. Conclusions: This study indicates that lactoferrin could be proposed as an alternative therapeutic approach for BV. Our data showed, for the first time, the dominance of Lactobacillus helveticus species during and after vaginal lactoferrin treatment.

[Use of probiotics in bacterial vaginosis]

INTRODUCTION

Bacterial vaginosis (BV) is a change in the vaginal microbiota due to bacterial overgrowth of normal microorganisms, which produces symptoms of vaginal discomfort, increased malodorous vaginal discharge, etc. Although they been seen to improve recurrence rates in clinical practice, the role of probiotics is questioned in these situations. A literature review on BV is presented in order to evaluate the effectiveness of using probiotics as adjuvant therapy in BV.

METHOD

PubMed, Cochrane and SCOPUS review of the last 5 years publications using probiotics to treat women diagnosed with BV.

RESULTS

An analysis was performed on the 10 items that refer to the use of probiotics in addition to antibiotic treatments.

CONCLUSIONS

All items conclude that the use of probiotics is beneficial in cases of BV in addition to conventional treatments. However, the conclusions are not categorical due to there being a wide variety of studies and probiotics used.

Randomized, double-blind, comparative study of oral metronidazole and tinidazole in treatment of bacterial vaginosis

OBJECTIVE

To compare the efficacy and tolerability of oral metronidazole and tinidazole in patients with bacterial vaginosis (BV) using Amsel's criteria.

PATIENTS AND METHODS

This was a randomized double-blind study, conducted by the Departments of Pharmacology and Gynecology of a tertiary care teaching hospital. Patients diagnosed with BV received either tablet metronidazole 500 mg twice daily for 5 days or tablet tinidazole 500 mg once daily + one placebo for 5 days and instructed to come for follow-up at the 1st week and 4th week. They were categorized as cured, partially cured, and not cured based on Amsel's criteria at the end of the study and compared between two groups using Chi-square test.

RESULTS

A total 120 women were enrolled in the study, of which 114 completed the study. The treatment arms were comparable. The cure rate with low-dose tinidazole was significantly more compared to metronidazole at 4th week (P = 0.0013), but not at 1st week (P = 0.242). The adverse drug reactions were less with tinidazole compared to metronidazole.

CONCLUSION

Tinidazole at lower dose offers a better efficacy than metronidazole in long-term cure rates and in preventing relapses with better side effect profile.

Antibiotic treatment for the sexual partners of women with bacterial vaginosis

BACKGROUND

Bacterial vaginosis (BV) is an infection that has a prevalence between 10% to 50% worlwide. BV results in an imbalance of the normal vaginal flora. Microorganisms associated with BV have been isolated from the normal flora of the male genital tract, and their presence could be related to the recurrence of BV after antibiotic treatment. Therefore, the treatment of sexual partners could decrease the recurrence of infection and possibly the burden of the disease.

OBJECTIVES

To assess the effectiveness in women and the safety in men of concurrent antibiotic treatment for the sexual partners of women treated for BV.

SEARCH METHODS

We searched the Cochrane Sexually Transmitted Infections Group Specialized Register (23 July 2016), CENTRAL (1991 to 23 July 2016), MEDLINE (1946 to 23 July 2016), Embase (1974 to 23 July 2016), LILACS (1982 to 23 July 2016), the World Health Organization (WHO) International Clinical Trials Registry Platform (ICTRP) (23 July 2016), ClinicalTrials.gov (23 July 2016) and the Web of Science™ (2001 to 23 July 2016). We also handsearched conference proceedings, contacted trial authors and reviewed the reference lists of retrieved studies.

SELECTION CRITERIA

Randomized controlled trials (RCTs) that compared the concurrent use of any antibiotic treatment with placebo, no intervention or any other intervention by the sexual partners of women treated for BV.

DATA COLLECTION AND ANALYSIS

Three review authors independently assessed trials for inclusion, extracted data and assessed the risk of bias in the included studies. We resolved any disagreements through consensus. We assessed the quality of the evidence using the GRADE approach.

MAIN RESULTS

Seven RCTs (1026 participants) met our inclusion criteria, and pharmaceutical industry funded four of these trials. Five trials (854 patients) compared any antibiotic treatment of sexual partners with placebo. Based on high quality evidence, antibiotic treatment does not increase the rate of clinical or symptomatic improvement in women during the first week (risk ratio (RR) 0.99, 95% confidence interval (CI) 0.96 to 1.03; 712 participants, four studies; RR 1.06, 95% CI 1.00 to 1.12; 577 patients, three studies, respectively), between the first and fourth week (RR 1.02, 95% CI 0.94 to 1.11; 590 participants, three studies; RR 0.93, 95% CI 0.84 to 1.03; 444 participants, two studies; respectively) or after the fourth week (RR 0.98, 95% CI 0.90 to 1.07; 572 participants, four studies; RR 1.03, 95% CI 0.90 to 1.17; 296 participants, two studies; respectively). Antibiotic treatment does not led to a lower recurrence during the first and fourth week (RR 1.28, 95% CI 0.68 to 2.43; 218 participants, one study; low quality evidence) or after the fourth week of treatment (RR 1.00, 95% CI 0.67 to 1.52; 372 participants, three studies; low quality evidence) in women, but increases the frequency of adverse events (most frequently gastrointestinal symptoms) reported by sexual partners (RR 2.55, 95% CI 1.55 to 4.18; 477 participants, three studies; low quality evidence). Two trials (172 participants) compared any antibiotic treatment for sexual partners with no intervention. When we compared it with no intervention, the effects of antibiotic treatment on recurrence rate after the fourth week (RR 1.71, 95% CI 0.65 to 4.55; 51 participants, one study), clinical improvement between the first and fourth week (RR 0.93, 95% CI 0.70 to 1.25; 152 participants, two studies) and symptomatic improvement after the fourth week (RR 0.66, 95% CI 0.39 to 1.11; 70 participants, one study) were imprecise and there were no differences between groups. We downgraded the quality of the evidence to low or very low.

AUTHORS' CONCLUSIONS

High quality evidence shows that antibiotic treatment for sexual partners of women with BV, compared with placebo, does not increase the rate of clinical or symptomatic improvement during the first, between the first and fourth or after the fourth week into the women. Low quality evidence suggests that antibiotic treatment does not led to a lower recurrence rate during the first and fourth or after the fourth week of treatment into the women, but increases the frequency of adverse events reported by sexual partners. Finally, compared with no intervention, antibiotic treatment does not decrease the recurrence rate after the fourth week and does not increase the frequency of clinical or symptomatic improvement between the first and fourth or after the fourth week into the women, respectively.

Treatment of bacterial vaginosis in pregnancy in order to reduce the risk of spontaneous preterm delivery - a clinical recommendation

INTRODUCTION

Bacterial vaginosis (BV) is characterized by a dysbiosis of the vaginal microbiota with a depletion of Lactobacillus spp. In pregnancy, prevalence's between 7 and 30% have been reported depending on the study population and the definition. BV may be associated with an increased risk of spontaneous preterm delivery (sPTD). However, it is controversial whether or not BV-positive pregnant women will benefit from treatment to reduce the risk of sPTD. We could not identify any good-quality guideline addressing this issue. Consequently we aimed to produce this clinical recommendation based on GRADE.

MATERIAL AND METHODS

Systematic literature searches were conducted in the following databases: Guidelines International Network: G-I-N, Medline, Embase, The Cochrane Database of Systematic Reviews, Web of Science and http://www.clinicaltrials.gov from 1999 to 3 October 2014. Hence, nine guidelines, 34 reviews, 18 randomized controlled trials and 12 observational studies were included.

RESULTS

The GRADE quality of evidence was consistently low or very low, primarily because none of the risk ratios (RR) for the risk of sPTD at <37 weeks were statistically significant. Concerning treatment with metronidazole, RR was 1.11 (95% CI 0.93-1.34) in low-risk pregnancies and 0.96 (95% CI 0.78-1.18) in high risk pregnancies. Concerning treatment with clindamycin at any gestational age, the RR was 0.87 (95% CI 0.73-1.05).

CONCLUSION

This systematic review gives a strong recommendation against treatment with metronidazole and a weak recommendation against treatment with clindamycin to reduce the sPTD rate in both high-risk and low-risk pregnancies with BV.

Profiles and technological requirements of urogenital probiotics

Probiotics, defined as live microorganisms that, when administered in adequate amounts, confer a health benefit on the host, are considered a valid and novel alternative for the prevention and treatment of female urogenital tract infections. Lactobacilli, the predominant microorganisms of the healthy human vaginal microbiome, can be included as active pharmaceutical ingredients in probiotics products. Several requirements must be considered or criteria fulfilled during the development of a probiotic product or formula for the female urogenital tract. This review deals with the main selection criteria for urogenital probiotic microorganisms: host specificity, potential beneficial properties, functional specifications, technological characteristics and clinical trials used to test their effect on certain physiological and pathological conditions. Further studies are required to complement the current knowledge and support the clinical applications of probiotics in the urogenital tract. This therapy will allow the restoration of the ecological equilibrium of the urogenital tract microbiome as well as the recovery of the sexual and reproductive health of women.

Vaginal colonisation by probiotic lactobacilli and clinical outcome in women conventionally treated for bacterial vaginosis and yeast infection

BACKGROUND

The aim of this study was to investigate the colonisation by lactobacilli and clinical outcome in women with bacterial vaginosis (BV) and recurrent vulvovaginal candidiasis (R-VVC) receiving antibiotic or anti-fungal treatment in combination with the probiotic EcoVag® capsules.

METHODS

A total of 40 Scandinavian women diagnosed with BV or VVC on the basis of Amsel's criteria or clinical symptoms were consecutively recruited in two pilot open label clinical trials. In trial I, women with BV were treated with clindamycin and metronidazole followed by vaginal EcoVag® capsules, containing Lactobacillus rhamnosus DSM 14870 and Lactobacillus gasseri DSM 14869, for 5 consecutive days after each antibiotic treatment. In trial II, women were recruited in three groups as follows: women with BV receiving clindamycin and metronidazole treatment together with a prolonged administration of EcoVag® (10 consecutive days after each antibiotic treatment followed by weekly administration of capsules for next four months), women with R-VVC receiving extended fluconazole and EcoVag® treatment, and women receiving extended fluconazole treatments only. The difference in frequency of isolation of EcoVag® strains or other lactobacilli between groups was compared by Fisher's exact test.

RESULTS

The 6-month cure rate for BV was 50 % in trial I while both the 6- and 12-month cure rates were 67 % in trial II. The 6- and 12-month cure rates for VVC were 100 % and 89 % in women receiving fluconazole and EcoVag®, and 100 % and 70 % in women receiving fluconazole only. The frequency of isolation of any Lactobacillus species during the course of the study was associated with cure of BV in trial I and II, whereas the frequency of isolation of EcoVag® strains was significantly associated with the cure of BV in trial II only. As previously observed, a change in sexual partner was associated with relapse of BV with an Odds ratio of 77 (95 % CI: 2.665 to 2225).

CONCLUSIONS

The study suggests that the treatment with antibiotics or anti-fungal medication in combination with EcoVag® capsules provide long-term cure against BV and R-VVC as compared to previous reports.

TRIAL REGISTRATION

ClinicalTrials.gov NCT02295579 . Registered November 20, 2014.

Penile Microbiota and Female Partner Bacterial Vaginosis in Rakai, Uganda

Bacterial vaginosis (BV) is a common vaginal bacterial imbalance associated with risk for HIV and poor gynecologic and obstetric outcomes. Male circumcision reduces BV-associated bacteria on the penis and decreases BV in female partners, but the link between penile microbiota and female partner BV is not well understood. We tested the hypothesis that having a female partner with BV increases BV-associated bacteria in uncircumcised men. We characterized penile microbiota composition and density (i.e., the quantity of bacteria per swab) by broad-coverage 16S rRNA gene-based sequencing and quantitative PCR (qPCR) in 165 uncircumcised men from Rakai, Uganda. Associations between penile community state types (CSTs) and female partner's Nugent score were assessed. We found seven distinct penile CSTs of increasing density (CST1 to 7). CST1 to 3 and CST4 to 7 were the two major CST groups. CST4 to 7 had higher prevalence and abundance of BV-associated bacteria, such as Mobiluncus and Dialister, than CST1 to 3. Men with CST4 to 7 were significantly more likely to have a female partner with a high Nugent score (P = 0.03). Men with two or more extramarital partners were significantly more likely to have CST4 to 7 than men with only marital partners (CST4 to 7 prevalence ratio, 1.84; 95% confidence interval [CI], 1.16 to 2.92). Female partner Nugent BV is significantly associated with penile microbiota. Our data support the exchange of BV-associated bacteria through intercourse, which may explain BV recurrence and persistence.

IMPORTANCE

Bacterial vaginosis (BV) is sexually associated but not considered a sexually transmitted disease. Our findings suggest that the uncircumcised penis is an important niche for BV-associated genital anaerobes. In addition, we found a link between extramarital sexual relationships and BV-associated bacteria in men, which parallels earlier findings of the association between sexual activity and BV in women. This suggests the sexual transmissibility of BV-associated bacteria. Reducing bacterial exchange by barrier methods and managing carriage of BV-associated bacteria in men may decrease BV persistence and recurrence in women.

[The influence of balneo- and peloid therapy on the characteristics of the hormonal regulation in the women presenting with bacterial vaginosis]

AIM

The objective of the present work was to study the influence of balneo- and peloid therapy on the characteristics of the hormonal regulation in the women presenting with bacterial vaginosis.

MATERIAL AND METHODS

The immunoenzymatic assay (ELISA) was used to study characteristics of hormonal regulation in 128 women presenting with bacterial vaginosis and normal prolactin level and 58 women with bacterial vaginosis and concomitant hyperprolactinemia. The study included the evaluation of dynamics of the clinical and laboratory parameters under the influence of peloidtherapy.

RESULTS

The application of the sulfide-containing siltypeloids was shown to have positive clinical effect on the adrenal and ovarian function and to exert the modulating action on the levels of the pituitary and sex hormones in women with bacterial vaginosis and normal prolactin levels. In contrast, the same treatment of the women with bacterial vaginosis and hyperprolactinemia causes a further deterioration of hormonal imbalance, increases the initially elevated prolactin level, aggravates disorders in the pituitary and ovarian regulation, and decreases the effectiveness of the treatment.

CONCLUSION

The results of the study suggest the necessity of the differential approach to the prescription of balneo- and peloid therapy to the patients with gynecological problems associated with hormonal disorders taking into account the level of prolactinemia.

The ring plus project: safety and acceptability of vaginal rings that protect women from unintended pregnancy

BACKGROUND

Research is ongoing to develop multipurpose vaginal rings to be used continuously for contraception and to prevent Human Immunodeficiency Virus (HIV) infection. Contraceptive vaginal rings (CVRs) are available in a number of countries and are most of the time used intermittently i.e. three weeks out of a 4-week cycle. Efficacy trials with a dapivirine-containing vaginal ring for HIV prevention are ongoing and plans to develop multi-purpose vaginal rings for prevention of both HIV and pregnancy have been elaborated. In contrast with the CVRs, multi-purpose vaginal rings will have to be used continuously. Women who continuously use a CVR will no longer have menses. Furthermore, some safety aspects of CVR use have never been studied in-depth in the past, such as the impact of the vaginal ring on the vaginal microbiota, biofilm formation and induction of inflammation. We studied acceptability and these novel aspects of safety in Rwandan women. Although significant progress has been made over the past decade, Rwanda still has a high unmet need for contraception (with 47% unplanned births) and a generalized HIV epidemic, and CVRs are not yet available.

METHODS

We will conduct an open label, single centre, randomized controlled trial. A total of 120 HIV-negative women will be randomized to intermittent CVR use (to allow menstruation) or continuous CVR use. Women will be followed for a maximum of 14 weeks. In parallel, we will conduct a qualitative study using in-depth interview and focus group discussion methodology.

DISCUSSION

In addition to evaluating the safety and acceptability of intermittent and continuous CVR use in Rwandan women, we hope that our findings will inform the development of future multipurpose vaginal rings, will prepare Rwandan study populations for future clinical trials of multipurpose vaginal rings, and will pave the way for introduction of CVRs on African markets.

TRIAL REGISTRATION

Clinicaltrials.gov NCT01796613 . Registered 14 February 2013.

Treatment of bacterial vaginosis: what we have and what we miss

INTRODUCTION

The disturbing, foul-smelling discharge of bacterial vaginosis (BV) is a nuisance to women. Treatment possibilities for BV are limited and only achieve complete cure in 65 to 85% of cases. In most women, the condition relapses within weeks to months after treatment.

AREAS COVERED

In search of new therapeutic actions to cure, prevent or delay recurrences of BV, PubMed and web of science were searched for papers with i) decent study layout, ii) proper statistics, iii) comparison group (placebo or standard treatment) and iv) language English, French, Dutch or German. The following keywords were used: bacterial vaginosis and treatment or management or therapy or prophylaxis or prevention. Results were grouped in treatment categories and were discussed.

EXPERT OPINION

Clindamycin and metronidazole are the standard drugs for BV. As other antibiotic and acidifying treatments are progressively being studied, like tinidazole, rifaximin, nitrofuran, dequalinium chloride, vitamin C and lactic acid, more options have become available for switching therapy, combining therapies and long-term prophylactic use to prevent recurrences. Further studies are needed. Also, adjuvant therapy with probiotics may have a significant role in improving efficacy and in preventing recurrences. However, it is unlikely that probiotics will replace antibiotherapy.

Behavioural and medical predictors of bacterial vaginosis recurrence among female sex workers: longitudinal analysis from a randomized controlled trial

Background

Data on risk factors of recurrent bacterial vaginosis (RBV) are still scarce. We used data from female sex workers (FSW) participating in a randomized controlled microbicide trial to examine predictors of BV recurrence.

Methods

Trial’s participants with at least an episode of BV which was treated and/or followed by a negative BV result and at least one subsequent visit offering BV testing were included in the analysis. Behavioural and medical data were collected monthly while laboratory testing for STI and genital tract infections were performed quarterly. The Andersen-Gill proportional hazards model was used to determine predictors of BV recurrence both in bivariate and multivariate analyses.

Results

440 women were included and the incidence rate for RBV was 20.8 recurrences/100 person-months (95% confidence interval (CI) =18.1–23.4). In the multivariate analysis controlling for the study site, recent vaginal cleansing as reported at baseline with adjusted hazard-ratio (aHR)=1.30, 95% CI = 1.02-1.64 increased the risk of BV recurrence, whereas consistent condom use (CCU) with the primary partner (aHR=0.68, 95% CI=0.49-0.93) and vaginal candidiasis (aHR=0.70, 95% CI=0.53-0.93), both treated as time-dependent variables, were associated with decreased risk of RBV.

Conclusion

This study confirms the importance of counselling high-risk women with RBV about the adverse effects of vaginal cleansing and the protective effects of condom use with all types of partners for the prevention of sexually transmitted infections, including BV. More prospective studies on risk factors of BV recurrence are warranted.

Trial registration

Trial registration: NCT00153777

Quantification of bacterial species of the vaginal microbiome in different groups of women, using nucleic acid amplification tests

Background

The vaginal microbiome plays an important role in urogenital health. Quantitative real time Polymerase Chain Reaction (qPCR) assays for the most prevalent vaginal Lactobacillus species and bacterial vaginosis species G. vaginalis and A. vaginae exist, but qPCR information regarding variation over time is still very limited. We set up qPCR assays for a selection of seven species and defined the temporal variation over three menstrual cycles in a healthy Caucasian population with a normal Nugent score. We also explored differences in qPCR data between these healthy women and an ‘at risk’ clinic population of Caucasian, African and Asian women with and without bacterial vaginosis (BV), as defined by the Nugent score.

Results

Temporal stability of the Lactobacillus species counts was high with L. crispatus counts of 10⁸ copies/mL and L. vaginalis counts of 10⁶ copies/mL. We identified 2 types of ‘normal flora’ and one ‘BV type flora’ with latent class analysis on the combined data of all women. The first group was particularly common in women with a normal Nugent score and was characterized by a high frequency of L. crispatus, L. iners, L. jensenii, and L. vaginalis and a correspondingly low frequency of L. gasseri and A. vaginae. The second group was characterized by the predominance of L. gasseri and L. vaginalis and was found most commonly in healthy Caucasian women. The third group was commonest in women with a high Nugent score but was also seen in a subset of African and Asian women with a low Nugent score and was characterized by the absence of Lactobacillus species (except for L. iners) but the presence of G. vaginalis and A. vaginae.

Conclusions

We have shown that the quantification of specific bacteria by qPCR contributes to a better description of the non-BV vaginal microbiome, but we also demonstrated that differences in populations such as risk and ethnicity also have to be taken into account. We believe that our selection of indicator organisms represents a feasible strategy for the assessment of the vaginal microbiome and could be useful for monitoring the microbiome in safety trials of vaginal products.

Efficacy of oral metronidazole with vaginal clindamycin or vaginal probiotic for bacterial vaginosis: randomised placebo-controlled double-blind trial

BACKGROUND

To determine if oral metronidazole (MTZ-400 mg bid) with 2% vaginal clindamycin-cream (Clind) or a Lactobacillus acidophilus vaginal-probiotic containing oestriol (Prob) reduces 6-month bacterial vaginosis (BV) recurrence.

METHODS

Double-blind placebo-controlled parallel-group single-site study with balanced randomization (1:1:1) conducted at Melbourne Sexual Health Centre, Australia. Participants with symptomatic BV [Nugent Score (NS) = 7-10 or ≥3 Amsel's criteria and NS = 4-10], were randomly allocated to MTZ-Clind, MTZ-Prob or MTZ-Placebo and assessed at 1,2,3 and 6 months. MTZ and Clind were administered for 7 days and Prob and Placebo for 12 days. Primary outcome was BV recurrence (NS of 7-10) on self-collected vaginal-swabs over 6-months. Cumulative BV recurrence rates were compared between groups by Chi-squared statistics. Kaplan-Meier, log rank and Cox regression analyses were used to compare time until and risk of BV recurrence between groups.

RESULTS

450 18-50 year old females were randomized and 408 (91%), equally distributed between groups, provided ≥1 NS post-randomization and were included in analyses; 42 (9%) participants with no post-randomization data were excluded. Six-month retention rates were 78% (n = 351). One-month BV recurrence (NS 7-10) rates were 3.6% (5/140), 6.8% (9/133) and 9.6% (13/135) in the MTZ-Clind, MTZ-Prob and MTZ-Placebo groups respectively, p = 0.13. Hazard ratios (HR) for BV recurrence at one-month, adjusted for adherence to vaginal therapy, were 0.43 (95%CI 0.15-1.22) and 0.75 (95% CI 0.32-1.76) in the MTZ-Clind and MTZ-Prob groups compared to MTZ-Plac respectively. Cumulative 6-month BV recurrence was 28.2%; (95%CI 24.0-32.7%) with no difference between groups, p = 0.82; HRs for 6-month BV recurrence for MTZ-Clind and MTZ-Prob compared to MTZ-Plac, adjusted for adherence to vaginal therapy were 1.09(95% CI = 0.70-1.70) and 1.03(95% CI = 0.65-1.63), respectively. No serious adverse events occurred.

CONCLUSION

Combining the recommended first line therapies of oral metronidazole and vaginal clindamycin, or oral metronidazole with an extended-course of a commercially available vaginal-L.acidophilus probiotic, does not reduce BV recurrence.

TRIAL REGISTRATION

ANZCTR.org.au ACTRN12607000350426.