Probiotics are a good choice for the treatment of bacterial vaginosis: a meta-analysis of randomized controlled trial.

BACKGROUND: Bacterial vaginosis (BV) is one of the most common vaginal infectious diseases in female reproductive period. Although the existing view is that probiotic treatment may be one of the feasible methods for the treatment of BV, different intervention methods lead to different treatment results. Therefore, up-to-date and comprehensive evidence in this regard is essential for the development of intervention strategies. OBJECTIVE: This meta-analysis aims to systematically evaluate the role of probiotics in the treatment of BV in adult women. METHODS: We searched the databases of Embase, Cochrane Library, PubMed, Web of Science and ClinicalTrials.gov for Randomized Controlled Trials published until November 7, 2021. Meta-analysis was performed by Revman5.3 software to systematically evaluate the clinical efficacy of probiotics adjunctive therapy in the treatment of BV. The literatures were screened and evaluated according to the inclusion and exclusion criteria. Chi-square test was used to test the heterogeneity between trials. Random or Fixed effect models were used to analyze the cure rate of BV. RESULTS: Fourteen randomized controlled trials compared the efficacy of probiotics with antibiotic therapy (probiotics + antibiotics group) versus antibiotics alone or plus placebo (antibiotics (+ placebo) group) for BV [Risk Ratios (RR) = 1.23, 95% CI (1.05, 1.43), P = 0.009]. Three compared the efficacy of probiotics regimen (probiotics group) and antibiotics (antibiotics group) in the treatment of BV [RR = 1.12, 95% CI (0.60, 2.07), P = 0.72]. Another Three compared the efficacy of probiotics regimen (probiotics group) with placebo (placebo group) [RR = 15.20, 95% CI (3.87, 59.64), P < 0.0001]. CONCLUSION: Our meta-analysis suggests probiotics may play a positive role in the treatment of BV, but more strong evidence is needed.

Our meta-analysis found that probiotics may play an active role in adjuvant treatment of bacterial vaginosis by conventional antibiotic therapy. It was emphasized that oral administration of L. rhamnose was more effective than vaginal application of L. rhamnose in the treatment of bacterial vaginosis. The therapeutic effect of probiotics varies with the administration route and dosage of probiotics.

Species-level resolution for the vaginal microbiota with short amplicons.

Specific bacterial species have been found to play important roles in human vagina. Achieving high species-level resolution is vital for analyzing vaginal microbiota data. However, contradictory conclusions were yielded from different methodological studies. More comprehensive evaluation is needed for determining an optimal pipeline for vaginal microbiota. Based on the sequences of vaginal bacterial species downloaded from NCBI, we conducted simulated amplification with various primer sets targeting different 16S regions as well as taxonomic classification on the amplicons applying different combinations of algorithms (BLAST+, VSEARCH, and Sklearn) and reference databases (Greengenes2, SILVA, and RDP). Vaginal swabs were collected from participants with different vaginal microecology to construct 16S full-length sequenced mock communities. Both computational and experimental amplifications were performed on the mock samples. Classification accuracy of each pipeline was determined. Microbial profiles were compared between the full-length and partial 16S sequencing samples. The optimal pipeline was further validated in a multicenter cohort against the PCR results of common STI pathogens. Pipeline V1-V3_Sklearn_Combined had the highest accuracy for classifying the amplicons generated from both the NCBI downloaded data (84.20% ± 2.39%) and the full-length sequencing data (95.65% ± 3.04%). Vaginal samples amplified and sequenced targeting the V1-V3 region but merely employing the forward reads (223 bp) and classified using the optimal pipeline, resembled the mock communities the most. The pipeline demonstrated high F1-scores for detecting STI pathogens within the validation cohort. We have determined an optimal pipeline to achieve high species-level resolution for vaginal microbiota with short amplicons, which will facilitate future studies.IMPORTANCEFor vaginal microbiota studies, diverse 16S rRNA gene regions were applied for amplification and sequencing, which affect the comparability between different studies as well as the species-level resolution of taxonomic classification. We conducted comprehensive evaluation on the methods which influence the accuracy for the taxonomic classification and established an optimal pipeline to achieve high species-level resolution for vaginal microbiota with short amplicons, which will facilitate future studies.