Probiotics in the treatment of vaginal infections: efficacy from the perspective of evidence-based medicine

The problem of vaginal infections in women (BV and VVC) remains relevant due to both the high prevalence and the lack of effectiveness of antimicrobial therapy and the risk of recurrence. One solution is to use probiotics, in particular probiotic lactobacilli that protect the vaginal environment from pathogens. The group of vaginal lactobacteria is dominated by L. crispatus, L. iners, L. jensenii, L. gasseri. Lactobacteria in the vaginal environment provide important protective functions against pathogens due to the production of lactic and other organic acids that maintain pH < 4.5, high ability to adhere to epithelium and aggregation, with the formation of biofilm and biosurfactants, inhibition of binding and adhesion of pathogenic bacteria, as well as products of antimicrobial substances such as H2O2, bacteriocins, and regulation of local epithelial immunity. Probiotic lactobacteria can be used both vaginally and orally, effectively colonizing the vaginal environment. Several meta-analyses of randomized clinical trials (RCTs) were performed to evaluate the efficacy of probiotics in combination with antibiotics and in monotherapy. The efficacy of probiotics in BV was confirmed in 4 meta-analyses, which showed a significant increase in the frequency of treatment (RR more than 1.53), including in monotherapy without antibiotics (RR more than 2.57). The efficiency of probiotics in oral use exceeded vaginal forms. In one meta-analysis of RCTs the efficacy of probiotic lactobacteria in VVC was confirmed both in achieving a higher cure rate in oral and vaginal use (RR 1,41 and RR 1,11 respectively), and in reducing the frequency of relapse (RR 0,34). Probiotics are included in clinical recommendations of the USA, Canada with the level of evidence I-II, as well as in domestic recommendations as the second stage of treatment after antimicrobial therapy.

Thus, the use of probiotics represents an alternative strategy and helps to improve treatment results through the restoration of the vaginal ecosystem.

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