Utilization of molecular methods to identify prognostic markers for recurrent bacterial vaginosis

Diagn Microbiol Infect Dis. 2016 Oct;86(2):231-42. doi: 10.1016/j.diagmicrobio.2016.07.003. Epub 2016 Jul 7.

Abstract

Background: Recurrent bacterial vaginosis (BV) after antimicrobial therapy is a major problem, affecting >50% of patients within 1 year. The objective of this study was to determine if prospective identification of patients at risk for recurrence using molecular methods is feasible.

Methods: Women were evaluated for BV by Amsel criteria and Nugent score. Vaginal specimens were analyzed using a panel of quantitative real-time polymerase chain reactions (qPCRs) at three times: pre-treatment, 7-10days post-treatment and 40-45days post-treatment. The PCRs quantified DNA of the following organisms: Gardnerella vaginalis; Atopobium vaginae; Bacterial Vaginosis-Associated Bacteria-1 (BVAB1), -2 (BVAB2) and -3 (BVAB3); Leptotrichia/Sneathia; Megasphaera Phylotypes 1 and 2; and Lactobacillus spp. (L. crispatus, L. gasseri, L. iners and L. jensenii).

Results: Out of 84 women diagnosed with BV (Amsel ≥3 and Nugent ≥4), 77 (91.7%) were successfully treated after 7-10days (asymptomatic and Amsel of either 0 or 1 with elevated vaginal pH and Nugent ≤6). Of these 77 women, 46 (59.7%) remained cured after 40-45days and 31 (40.3%) developed recurrent BV. In univariate analysis, we found that women who would have recurrent BV during the study had greater concentrations of Megasphaera Phylotype 2 (P=0.001) and BVAB2 (P=0.015) at initial diagnosis and greater vaginal pH (P=0.030), higher Nugent score (P=0.043) and a greater concentration of G. vaginalis (P=0.012) post-treatment, when compared to women who were cured during the study. These differences largely remained when cure was defined as Nugent ≤3 or when only women treated with intravaginal metronidazole were evaluated.

Conclusion: Molecular analysis of BV is a useful adjunct to clinical and microscopic analysis to prospectively identify patients at high risk for recurrent BV.

Keywords: Bacterial vaginosis; Gardnerella vaginalis; qPCR.

MeSH terms

  • Adolescent
  • Adult
  • Anti-Infective Agents / therapeutic use
  • Bacteria / classification*
  • Bacteria / genetics*
  • Bacterial Load
  • Female
  • Humans
  • Longitudinal Studies
  • Middle Aged
  • Prognosis
  • Real-Time Polymerase Chain Reaction
  • Recurrence
  • Risk Factors
  • Vaginosis, Bacterial / drug therapy
  • Vaginosis, Bacterial / epidemiology*
  • Vaginosis, Bacterial / microbiology*
  • Young Adult

Substances

  • Anti-Infective Agents