Treating vaginitis with probiotics in non-pregnant females: A systematic review and meta-analysis

Simultaneous application of oral and intravaginal probiotics for Helicobacter pylori and its antibiotic-therapy-induced vaginal dysbacteriosis

Helicobacter pylori is a prevalent bacterial pathogen globally, implicated in various gastrointestinal disorders. Current recommended antibiotic therapies for H. pylori infection have been proven to be therapeutically insufficient, with low eradication rates and high recurrence rates. Emerging evidence suggests that antibiotic therapy for H. pylori can lead to gastrointestinal and subsequent vaginal dysbiosis, posing challenges for conventional antibiotic approaches. Thus, this article proposes a novel probiotic therapy involving simultaneous oral and intra-vaginal probiotic administration alongside antibiotics for H. pylori treatment, aiming to enhance eradication rates and mitigate dysbiosis. We begin by providing an overview of gastrointestinal and vaginal microbiota and their interconnectedness through the vagina-gut axis. We then review the efficacy of current antibiotic regimens for H. pylori and discuss how antibiotic treatment impacts the vaginal microenvironment. To explore the feasibility of this approach, we evaluate the effectiveness of oral and intra-vaginal probiotics in restoring normal microbiota in the gastrointestinal and vaginal tracts, respectively. Additionally, we analyze the direct mechanisms by which oral and intra-vaginal probiotics act on their respective tracts and discuss potential cross-tract mechanisms. Considering the potential synergistic therapeutic effects of probiotics in both the gastrointestinal and vaginal tracts, dual-channel probiotic therapy holds promise as a more effective approach for H. pylori eradication and dysbiosis mitigation, presenting a novel concept in the collaborative treatment of gastrointestinal and genital disorders.

Efficacy of Dequalinium Chloride vs Metronidazole for the Treatment of Bacterial Vaginosis: A Randomized Clinical Trial

Importance

Bacterial vaginosis (BV) is a common cause of vaginal infection. First-line treatments of BV are metronidazole and clindamycin. Due to the increase in antibiotic resistance, effective nonantibiotic treatments for BV are needed.

Objective

To examine whether dequalinium chloride, a broad-spectrum antiseptic, is noninferior to oral metronidazole for the treatment of BV.

Design, Setting, and Participants

This phase 4, multicenter, triple-blind, double-dummy, parallel, noninferiority randomized clinical trial was conducted from July 29, 2021, to August 25, 2022, with a 1-month follow-up. Participants were premenopausal women 18 years or older with BV from 11 gynecologic practices and 1 hospital in Poland, Slovakia, and the Czech.

Intervention

Patients were randomized to treatment with dequalinium chloride vaginal tablets (10 mg once daily for 6 days) or oral metronidazole (500 mg twice daily for 7 days). Double-dummy medication kits contained vaginal and oral tablets with placebo and active medication.

Main Outcomes and Measures

The main outcome was the noninferiority margin (of 15 percentage points) in the absolute difference in clinical cure rates between dequalinium chloride and metronidazole 7 to 11 days after start of treatment (visit 1). Noninferiority was met if the lower 95% CI for the difference in clinical cure rate was less than 15 percentage points at visit 1.

Results

A total of 147 women (mean [SD] age, 36.7 [9.0] years) were treated with dequalinium chloride (n = 72) or metronidazole (n = 75). The clinical cure rates at visit 1 were 64 of 69 (92.8%) for dequalinium chloride vs 69 of 74 (93.2%) for metronidazole in the intention-to-treat population, whereas in the per-protocol population, cure rates were 54 of 58 (93.1%) for dequalinium chloride vs 48 of 53 (90.6%) for metronidazole. The treatment differences of -0.5 percentage points (95% CI, -10.8 to 9.8 percentage points; P = .002) in the intention-to-treat population and 2.5 percentage points (95% CI, -9.4 to 14.4 percentage points; P = .001) in the per-protocol population confirmed the noninferiority of dequalinium chloride. The tolerability of dequalinium chloride was rated as very good by 30 of 50 patients (60.0%) but only by 21 of 54 (38.9%) for metronidazole. Three patients in the metronidazole group suspended treatment due to an adverse event.

Conclusions and Relevance

This randomized clinical trial showed that dequalinium chloride was not inferior to metronidazole for the treatment of BV. Dequalinium chloride had a similarly high cure rate but with better tolerability and fewer adverse events. With a similar efficacy to metronidazole and clindamycin, dequalinium chloride warrants consideration as first-line treatment for BV to help reduce antibiotic consumption.

Trial Registration

EudraCT: 2020-002489-15.

Vaginal colonization of women after oral administration of Lactobacillus crispatus strain NTCVAG04 from the human microbiota

BACKGROUND

The genomic approach has deeply changed the microbiology perspective, mainly concerning the microbioma identification. In this regard, some microbes colonize the healthy vagina. Vaginitis is a common gynecological ailment and includes bacterial vaginosis (BV), usually caused by local dysbiosis, such as a microbiota imbalance. Lactobacilli are the most prevalent bacteria colonizing the healthy vagina, so guaranteeing local eubiosis. In particular, vaginal colonization by L. crispatus is associated with low susceptibility to BV. Therefore, probiotics, such as life bacteria providing health advantages, are a current strategy in the prevention or treatment of vaginitis, including BV. However, there is a low level of evidence that probiotics after ingestion could really colonize the vagina. In particular, no study evidenced that L. crispatus after ingestion can colonize vagina. Therefore, the current study explored the capacity of Biovaginil® (NTC, Milan, Italy) dietary supplement containing Lactobacillus crispatus NTCVAG04 and vitamin A to colonize the gut and vagina in women with a history of vaginitis/vaginosis.

METHODS

Twenty fertile females (mean age 34.0 years) were enrolled in the study. Rectal and vaginal swabs were collected at baseline and after the first and second cycle of Biovaginil®. Each cycle lasted 14 days within two consecutive menstrual periods.

RESULTS

Seven women were excluded from the analysis because the samples were technically not evaluable. One woman dropped out because of mild adverse event. At the end of the study, nine women (75%) had positive rectal swab for L. crispatus NTCVAG04, and 8 of them also had positive vaginal swab.

CONCLUSIONS

The current study provided the first evidence that L. crispatus NTCVAG04, administered by two Biovaginil® courses, colonized both the gut and vagina. Moreover, the L. crispatus NTCVAG04 strain could be considered the archetype of a new class of oral probiotics that actively colonize the vagina, and that could be called "colpobiotics."

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.

In Vitro Assessment of Lactobacillus crispatus UBLCp01, Lactobacillus gasseri UBLG36, and Lactobacillus johnsonii UBLJ01 as a Potential Vaginal Probiotic Candidate

In this study, Lactobacillus crispatus UBLCp01, Lactobacillus gasseri UBLG36, and Lactobacillus johnsonii UBLJ01 isolated from the vagina of healthy reproductive age Indian women were screened for beneficial probiotic properties. These strains showed the ability to survive acidic and simulated vaginal fluid conditions and could adhere to mucin. Lact. gasseri UBLG36, and Lact. johnsonii UBLJ01 produced D- and L-lactic acid, whereas Lact. crispatus UBLCp01 produced hydrogen peroxide and D- and L-lactic acid. All strains inhibited the growth of pathogens (Escherichia coli, Gardnerella vaginalis, Proteus mirabilis, and Candida albicans) and were capable of co-aggregating with them with varying degrees. Strains secreted exopolysaccharides and formed biofilms under in vitro conditions. Safety assessment showed that these strains had a usual antibiotic susceptibility profile, did not produce hemolysins, gelatinases, and mucin degrading enzymes. Based on strain characteristics and beneficial properties, we believe that these strains are promising candidates for human trials to confirm their ability to prevent/treat vaginal dysbiosis and maintain a healthy vaginal eco-system.

Lacticaseibacillus rhamnosus CA15 (DSM 33960) strain as a new driver in restoring the normal vaginal microbiota: A randomized, double-blind, placebo-controlled clinical trial

Probiotics play a key role in maintaining the health of the female reproductive tract, representing a promising alternative to safeguard or restore the homeostasis of the vaginal microbiota. The present randomized double-blind placebo-controlled study was performed to evaluate the ability of the potential probiotic Lacticaseibacillus rhamnosus CA15 (DSM 33960) strain, orally administrated, to balance the vaginal microbiota of women with vaginal dysbiosis. Sixty women, with signs and symptoms of vaginal dysbiosis, were recruited and randomly allocated to receive oral capsules containing the L. rhamnosus CA15 (DSM 33960) strain at 1.0 × 10¹⁰ colony-forming units or placebo once daily for 10 days. Clinical and microbiological parameters were evaluated in three scheduled appointments: at baseline (T0), 10 days after the start of the treatment (T1), and 30 days after the end of the treatment (T2). In addition, the quality of life, through the WHO quality of life assessment questionnaire, was assessed at baseline (T0) and 30 days after the end of the treatment (T2). The probiotic was well tolerated and no side effects were reported. The oral consumption of the potential probiotic L. rhamnosus CA15 (DSM 33960) strain determined a significant improvement of both clinical signs and symptoms not only 10 days after the start of the treatment (T1) but also 30 days after the end of the treatment (T2). A significant reduction of potential pathogens and a concomitant increase of lactobacilli was revealed, by microbial count, at both T1 and T2 sampling times. In addition, the enhancement of the perceived physical health, social relations, and environment was reported. Differently, in placebo group clinical and microbiological parameters as well as quality of life remained almost unchanged. The potential probiotic L. rhamnosus CA15 (DSM 33960) strain could be a safe and effective approach to restore and maintain a balanced vaginal microbiota.

Microbial Diversity and Pathogenic Properties of Microbiota Associated with Aerobic Vaginitis in Women with Recurrent Pregnancy Loss

Recurrent pregnancy loss (RPL) is a major reproductive problem that affects approximately 5% of couples. The objective of this study was to assess vaginal flora dysbiosis in women suffering from unexplained RPL and to investigate the pathogenic properties of the microbiota associated with aerobic vaginitis (AV). The study included one hundred fifteen women, 65 with RPL and 50 controls. The diversity of vaginal microbiota isolated was evaluated by molecular sequencing. Then, pathogenic factors, such as acid-resistance, antibiotics susceptibility, and biofilm formation were evaluated. The prevalence of AV was five-fold higher in the RPL group than in the controls (64.6% vs. 12.0%). The most prevalent isolates in the case group were Enterococcus spp. (52%) and Staphylococcus spp. (26%). All bacterial strains tolerate low pH. The prevalence of multidrug resistance (MDR) among all bacteria was 47.7%. Of all strains, 91.0% were biofilm producers. The presence of MDR was found to be related to biofilm formation. The results provide evidence supporting an increased presence of dysbiosis of the vaginal flora, especially AV, in women with RPL in Tunisia. The viability of the AV-associated bacteria and their persistence in the genitals may be due to their ability to resist low pH and to produce a biofilm.

Probiotics, a promising therapy to reduce the recurrence of bacterial vaginosis in women? a systematic review and meta-analysis of randomized controlled trials

Introduction

The evidence for probiotic efficacy in preventing bacterial vaginosis (BV) recurrences among women aged 18 years and above is sparse. We aimed to ascertain the efficacy of probiotics in preventing BV recurrences after at least one menstrual cycle in this population.

Methods

We conducted a systematic literature search using PubMed, MEDLINE (Ovid interface), Web of Science (WoS), Scopus, Embase, ProQuest Dissertations and Theses Global, Cochrane Library databases and registries comprised of Open Science Framework (OSF) preprints registry, the ClinicalTrials.gov (USA), WHO International Clinical Trials Registry Platform (WHO-ICTRP), International Standard RCT Number (ISRCTN) registry, limited to randomized clinical trials (RCTs) in English published between January 2000 and December 2021. The inclusion criteria were trials that administered probiotics to BV-positive women in an experimental arm of at least 20 samples. The usage of probiotics should be preceded with standard antibiotic regimen and followed by a reassessment of BV status after at least a single menstrual cycle. Risk of bias assessment was completed using revised Cochrane risk-of-bias tool for randomized trials (RoB 2). The PROSPERO registration number of the review is CRD42022302044.

Results

From 8,162 identified records, we included 10 studies (n = 1,234 participants) for final analysis; 7 trials compared probiotics vs. placebo, whereas 3 trials compared probiotics vs. metronidazole alone. Using random-effects meta-analysis, probiotics were shown to reduce the risk of BV recurrences by 45% compared to either placebo or metronidazole [14.8 vs. 25.5%, RR: 0.55 (95%CI: 0.33, 0.91), p = 0.03, I2 = 45.4% (95%CI: 0, 73.7%)]. Sensitivity analysis revealed the robustness of results upon removal of studies with high risk of bias [RR: 0.54 (95%CI: 0.38, 0.77), p = 0.006] and reporting bias (RR: 0.53, 95%CI: 0.39, 0.74, p = 0.002). Meta-regression demonstrated that the route of administration (pvaginal = 0.67; poral = 0.44), the total dosage of probiotics (p = 0.17), cumulative days of probiotic administration (p = 0.76), and the number of species in probiotic preparation (p = 0.40) were not linked to BV recurrences.

Interpretation

Probiotics were associated with more than twofold reduction in BV recurrences when BV status was assessed after at least 1-month postintervention. Further high-quality and methodologically standardized RCTs should evaluate probiotic efficacy for BV prevention in a diverse community setting.

Systematic review registration

[https://www.crd.york.ac.uk/prospero/display_record.php?ID=CRD42021290613], identifier [CRD42021290613].

The role of probiotics in vaginal health

Probiotics have been widely used in the treatment of intestinal diseases, but the effect of probiotics on female reproductive tract health is still controversial. Lactobacillus is the most abundant microorganism in the vagina, which is related to the vaginal mucosal barrier. Lactobacillus adheres to the vaginal epithelium and can competitively antagonize the colonization of pathogens. The factors produced by Lactobacillus, such as bacteriocin and hydrogen peroxide (H₂O₂), can inhibit the growth of pathogenic microorganisms and maintain the low pH environment of the vagina. Probiotics play an important role in maintaining the stability of vaginal microenvironment, improving immune defense and blocking the progression of cervical cancer. We review the research progress of probiotics represented by Lactobacillus in gynecological diseases such as human papilloma virus (HPV) infection, bacterial vaginosis (BV) and Genitourinary Syndrome of Menopause (GSM), so as to provide basis for further exerting the role of probiotics in women’s health.

Lactobacillus acidophilus, L. plantarum, L. rhamnosus, and L. reuteri Cell-Free Supernatants Inhibit Candida parapsilosis Pathogenic Potential upon Infection of Vaginal Epithelial Cells Monolayer and in a Transwell Coculture System In Vitro

Vulvovaginal candidiasis (VVC) is a common clinical condition with symptoms and signs of vaginal inflammation in the presence of Candida species. At least one episode of VVC is experienced in up to 75% of women in the reproductive age group during their lifetime, and 5% to 8% of such women suffer from the chronic form. Most cases of VVC are still caused by C. albicans. However, the incidence of VVC cases by non-albicans Candida (NAC) species, such as C. parapsilosis, is continuously increasing. Despite the prevalence of VVC from NAC, little is known about these species and almost nothing about the mechanisms that trigger the VVC. Lactobacillus spp. are the most widely before represented microorganisms in the vaginal microbiota of healthy women. Here, cell-free supernatants (CFS) obtained from L. acidophilus, L. plantarum, L. rhamnosus, and L. reuteri were assessed for their effect on C. parapsilosis virulence traits. Moreover, we assessed if such an effect persisted even after the removal of the CFS (CFS preincubation effect). Moreover, a transwell coculture system was employed by which the relevant antifungal effect was shown to be attributable to the compounds released by lactobacilli. Our results suggest that lactobacilli can work (i) by reducing C. parapsilosis virulence traits, as indicated by the reduced fungal proliferation, viability, and metabolic activity, and (ii) by improving epithelial resistance to the fungus. Overall, these data suggest that, in the context of the vaginal microbiota, the lactobacilli may play a role in preventing the onset of mucosal C. parapsilosis infection. IMPORTANCE The incidence of VVC by non-albicans Candida (NAC) species, such as C. parapsilosis, is increasing. Treatment failure is common in NAC-VVC because some species are resistant or poorly susceptible to the antifungal agents normally employed. Research on C. parapsilosis's pathogenic mechanisms and alternative treatments are still lacking. C. albicans triggers the VVC by producing hyphae, which favor the loss of epithelial tolerance. Differently, C. parapsilosis only produces pseudohyphae. Hence, different virulence factors may trigger the VVC. Likewise, the therapeutic options could also involve different fungal targets. Substantial in vitro and in vivo studies on the pathogenicity mechanisms of C. parapsilosis are lacking. The data presented here ascribe a novel beneficial role to different Lactobacillus spp., whose CFS provides a postbiotic-like activity against C. parapsilosis. Further studies are needed to unravel the mechanisms involved in the bioactivities of such compounds, to better understand the role of single postbiotics in the CFS.

The Antibiofilm Role of Biotics Family in Vaginal Fungal Infections

“Unity in strength” is a notion that can be exploited to characterize biofilms as they bestow microbes with protection to live freely, escalate their virulence, confer high resistance to therapeutic agents, and provide active grounds for the production of biofilms after dispersal. Naturally, fungal biofilms are inherently resistant to many conventional antifungals, possibly owing to virulence factors as their ammunitions that persistently express amid planktonic transition to matured biofilm state. These ammunitions include the ability to form polymicrobial biofilms, emergence of persister cells post-antifungal treatment and acquisition of resistance genes. One of the major disorders affecting vaginal health is vulvovaginal candidiasis (VVC) and its reoccurrence is termed recurrent VVC (RVVC). It is caused by the Candida species which include Candida albicans and Candida glabrata. The aforementioned Candida species, notably C. albicans is a biofilm producing pathogen and habitually forms part of the vaginal microbiota of healthy women. Latest research has implicated the role of fungal biofilms in VVC, particularly in the setting of treatment failure and RVVC. Consequently, a plethora of studies have advocated the utilization of probiotics in addressing these infections. Specifically, the excreted or released compounds of probiotics which are also known as postbiotics are being actively researched with vast potential to be used as therapeutic options for the treatment and prevention of VVC and RVVC. These potential sources of postbiotics are harnessed due to their proven antifungal and antibiofilm. Hence, this review discusses the role of Candida biofilm formation in VVC and RVVC. In addition, we discuss the application of pro-, pre-, post-, and synbiotics either individually or in combined regimen to counteract the abovementioned problems. A clear understanding of the role of biofilms in VVC and RVVC will provide proper footing for further research in devising novel remedies for prevention and treatment of vaginal fungal infections.

Healthy Vaginal Microbiota and Influence of Probiotics Across the Female Life Span

Vaginal microbiota plays a central role in women’s health and reproduction. Vaginal microbiota is dynamic and shaped by hormonal shifts in each stage of a woman’s life from pre-puberty to postmenopause. Current research has mainly focused on vaginal bacterial and fungal members of the community and emphasized their role in disease. However, the impact of balanced vaginal microbiota on health and its interaction with the host is yet poorly understood. High abundance of vaginal lactobacilli is most strongly associated with health, but the concept of health may vary as vaginal dysbiosis may be asymptomatic. Furthermore, there is a lot of variation between ethnic groups in terms of dominating vaginal bacteria. Probiotic lactobacilli could be a safe and natural means to balance and maintain healthy vaginal microbiota. Research evidence is accumulating on their role in supporting women’s health throughout life. This review describes the current literature on vaginal microbiota, the major factors affecting its composition, and how the communities change in different life stages. Furthermore, we focused on reviewing available literature on probiotics and their impact on vaginal microbiota and health.

A New Therapy for Uncomplicated Vulvovaginal Candidiasis and Its Impact on Vaginal Flora

Background: An estimated 75% of women will have one episode of vulvovaginal candidiasis (VCC) during their lifetime, and 40–50% of these will experience further episodes. The high incidence of vulvovaginal candidiasis, combined with the problems of azole resistance and toxicity, highlights the necessity for new strategies for the treatment of this condition. In this context, natural compounds represent promising alternatives. Methods: We enrolled, between January 2020 and April 2021, forty women affected by uncomplicated vulvovaginal candidiasis. Women were divided into two groups. In the first group, we treated 20 women with clotrimazole daily administration for six days. In the second group, 20 women were treated with clotrimazole associated with Unilen^® Microbio+, a new product containing Saccharomyces cerevisiae, melatonin, and GLA-14. Women underwent a check at days 15, 30, and 90. A clinical and cultural examination were performed to establish the effect of the treatments on vaginal flora. Results: In the group treated with Unilen^® Microbio+, clinical and microbiological cure at 15 and 30 days was observed in 18 women (90%), compared with 16 women (80%) in the group treated only with clotrimazole. The efficacy of the association between clotrimazole and Unilen^® Microbio+ in these uncomplicated forms was therefore not inferior to the azole treatment alone. Only four women (20%) in the Unilen^® Microbio+ group presented symptomatic recurrences within the 3 months, compared with eight women (40%) in the clotrimazole-only group. Microscopic wet mount analysis at 1 and 3 months demonstrated a significant increase in lactobacillus count and a reduction in the polymorphonucleate cells in the Unilen^® Microbio+ group. Conclusions: Unilen^® Microbio+ supplementation was demonstrated to cure uncomplicated vulvovaginal candidiasis with clotrimazole, reducing recurrence and improving vaginal flora better than clotrimazole treatment alone.

A clinical pilot study on the effect of the probiotic Lacticaseibacillus rhamnosus TOM 22.8 strain in women with vaginal dysbiosis

Lactobacilli with probiotic features play an essential role in maintaining a balanced vaginal microbiota and their administration has been suggested for the treatment and prevention of vaginal dysbiosis. The present study was aimed to in vitro and in vivo investigate the probiotic potential of the Lacticaseibacillus rhamnosus TOM 22.8 strain, isolated from the vaginal ecosystem of a healthy woman. For this purpose, safety and functional properties were in depth evaluated. The strain exhibited a broad spectrum of antagonistic activity against vaginal pathogens; adhesion capacity to both the vaginal VK2/E6E7 and the intestinal Caco-2 cells; anti-inflammatory and antioxidant activities, suggesting its promising probiotic features. In addition, an in vivo pilot-study was planned. Based on both clinical and microbiological parameters, the oral or vaginal strain administration, determined a significant pathogens reduction after 10 days of administration and a maintenance of eubiosis up to 30 days after the end of the treatment. Therefore, the L. rhamnosus TOM 22.8 strain can be proposed as valuable oral and/or vaginal treatment for vaginal dysbiosis.