Evidence-based mixture containing Lactobacillus strains and lactoferrin to prevent recurrent bacterial vaginosis: a double blind, placebo controlled, randomised clinical trial

Characterization of vaginal microbiota in women with preterm labor with intra-amniotic inflammation

This study aims to investigate the relation between vaginal microbiota and exposition to intra-amniotic inflammation (IAI). We conducted a prospective cohort study in women with preterm labor <34 weeks who had undergone amniocentesis to rule out IAI. Vaginal samples were collected after amniocentesis. Women with IAI included those with positive amniotic fluid (AF) for a microorganism identified by specific culture media and Sanger sequencing 16S ribosomal RNA gene and/or high AF interleukin (IL)-6 levels. Vaginal microbiota was characterized by 16S ribosomal RNA gene amplicon sequencing. Specific quantitative PCR targeted to Lactobacillus spp. was also performed. Regression models were used to evaluate associations between vaginal microbiota and exposition to IAI. Concerning our results, 64 women were included. We observed an inverse association between AF IL-6 levels and load of Lactobacillus spp. Depletion in Lactobacillus spp. load was significantly associated with an early gestational age at delivery and a short latency to delivery. Microbial-diversity was found to be a risk factor for the subsequent occurrence of clinical chorioamnionitis. To the contrary, higher Lactobacillus spp. load had a protective role. In conclusion, the study identifies reduced bacterial load of Lactobacillus spp. in women exposed to IAI and found microbial-diversity and Lactobacillus spp. depletion to be associated with a worse perinatal outcome.

Probiotics for the treatment of women with bacterial vaginosis: A systematic review and meta-analysis of randomized clinical trials

This systematic review and meta-analysis systematically evaluated the efficacy of probiotic monotherapy and combination therapy for bacterial vaginosis (BV). Published randomized controlled trials were searched in the Cochrane Library, PubMed, EMBASE, OVID Database and ClinicalTrials.gov from the inception dates to 12 July 2019. The literature was screened and evaluated according to the inclusion criteria, and the data were analysed by a random effect model. A chi-square test was used to test heterogeneity between trials. This study included 13 randomized controlled trials (RCTs), which included 1258 patients, and the cure rate of BV was analysed. Three RCTs compared probiotics with a placebo (control) [risk ratios (RR) = 4.39, 95% CI (2.05, 9.41), P = 0.0001]. Two RCTs compared probiotics with antibiotics (control) [RR = 1.03, 95% CI (0.38, 2.81), P = 0.95]. Nine of 13 RCTs compared the combination of probiotics and antibiotics with antibiotics alone [RR = 1.28, 95% CI (1.05, 1.56), P = 0.02]. Despite the high heterogeneity of the pooled analysis, neither the subgroup analysis results nor the sensitivity analysis results were statistically significant. Probiotics may have a positive effect on the treatment of BV, but there is a lack of strong evidence.

The Impact of Lactoferrin on the Growth of Intestinal Inhabitant Bacteria

Lactoferrin (Lf) is an iron-binding milk glycoprotein that promotes the growth of selected probiotic strains. The effect of Lf on the growth and diversification of intestinal microbiota may have an impact on several issues, including (i) strengthening the permeability of the epithelial cell monolayer, (ii) favoring the microbial antagonism that discourages the colonization and proliferation of enteric pathogens, (iii) enhancing the growth and maturation of cell-monolayer components and gut nerve fibers, and (iv) providing signals to balance the anti- and pro-inflammatory responses resulting in gut homeostasis. Given the beneficial role of probiotics, this contribution aims to review the current properties of bovine and human Lf and their derivatives in in vitro probiotic growth and Lf interplay with microbiota described in the piglet model. By using Lf as a component in pharmacological products, we may enable novel strategies that promote probiotic growth while conferring antimicrobial activity against multidrug-resistant microorganisms that cause life-threatening diseases, especially in neonates.

Variations in Vaginal, Penile, and Oral Microbiota After Sexual Intercourse: A Case Report

Background: Bacterial vaginosis is the most common infection in women and it has been proved that dysbiosis of vaginal microbiota can promote the infectious status. This case report shows the effect of oral and vaginal sex over the microbiota of a heterosexual couple who reported repeated problems of vaginal and oral infections after sexual intercourse. Case Presentation: A woman (32) reported to have vaginal infections and gingivitis after she had started a relationship with a man (34) and associated them with unprotected sex. No treatments successfully removed the problem and it repeated every time they had sexual encounters. Vaginal, penile and oral swabs were collected before and after sexual encounters in order to analyze changes in the respective microbiotas. DNA was extracted from all samples and the bacterial 16S rRNA gene was sequenced using Illumina MiSeq. Conclusions: Lactobacillus occupied the great majority of the vaginal microbiota in all scenarios except after unprotected sex, which caused a bacterial dysbiosis that lasted at least for a week. Similarly, the penile microbiota changed significantly after unprotected sexual relationships. Interestingly, both oral and vaginal sex increased the abundance of Lactobacillus in the male oral and penile microbiota, respectively. In conclusion, unprotected sexual intercourse influenced the genital microbiota in the couple studied and future studies with larger sample sizes should study if sex may be a factor promoting vaginal infection through dysbiosis and hampered protection by the resident microbiota.

Conventional oral and secondary high dose vaginal metronidazole therapy for recurrent bacterial vaginosis: clinical outcomes, impacts of sex and menses

Purpose

Oral metronidazole therapy is the standard of care for bacterial vaginosis (BV), yet it has alarming rates of recurrence and refractory responses among recurrent BV (RBV) patients. This study addresses whether high dose vaginal metronidazole therapy (HDM) is beneficial in RBV patients who fail after standard of care (SOC) therapy, whether diagnostic test scores proximal to the HDM predict clinical outcome, and whether menses, coitus, or race influences therapy outcome.

Patients and methods

A total of 90 patients with RBV were given SOC and tracked 74 for up to 9 months. Refractory or recurrent patients (57) with symptomatic BV were given HDM and followed for up to 8 months. Patients were evaluated by Amsel criteria, Nugent score, and a qPCR assay that assesses the Lactobacillus content.

Results

HDM achieved at least short-term remission in 68% of the patients who were refractory to or recurred after SOC and provided a 10-day increase in the mean duration of remission among patients who eventually recurred (p=0.027). Patients with prolonged dysbiosis (pH >5 or Amsel 4) before symptomatic recurrence were more likely to recur after subsequent HDM. Most recurrence happened within 10 days of menses, but sex in this cohort was not associated with clinical outcome. Mean diagnostic BV scores of African American patients in remission were inferior to scores of a small cohort of Caucasian patients in remission.

Conclusion

Encouraging results obtained with HDM justify a prospective, randomized study to determine if follow-up HDM is beneficial among a broader cohort of women failing conventional oral metronidazole therapy.