Bacterial Communities in Women with Bacterial Vaginosis: High Resolution Phylogenetic Analyses Reveal Relationships of Microbiota to Clinical Criteria

Sujatha Srinivasan,Frederick A Matsen,David N Fredricks,Frederick J Ross,Roger Bumgarner,Tina L Fiedler,Martin T Morgan,Jeanne M Marrazzo,Connor O Mccoy,Robert W Hall,Noah G Hoffman,Adam J Ratner

doi:10.1371/journal.pone.0037818

Sujatha Srinivasan, Frederick A Matsen + Show 10 more

Open Access

https://doi.org/10.1371/journal.pone.0037818

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Journal: PLoS ONE	Publication Date: Jun 18, 2012
Citations: 554	License type: CC BY 4.0

Affiliation: Fred Hutch Cancer Center, University of Washington

Abstract

BackgroundBacterial vaginosis (BV) is a common condition that is associated with numerous adverse health outcomes and is characterized by poorly understood changes in the vaginal microbiota. We sought to describe the composition and diversity of the vaginal bacterial biota in women with BV using deep sequencing of the 16S rRNA gene coupled with species-level taxonomic identification. We investigated the associations between the presence of individual bacterial species and clinical diagnostic characteristics of BV.Methodology/Principal FindingsBroad-range 16S rRNA gene PCR and pyrosequencing were performed on vaginal swabs from 220 women with and without BV. BV was assessed by Amsel’s clinical criteria and confirmed by Gram stain. Taxonomic classification was performed using phylogenetic placement tools that assigned 99% of query sequence reads to the species level. Women with BV had heterogeneous vaginal bacterial communities that were usually not dominated by a single taxon. In the absence of BV, vaginal bacterial communities were dominated by either Lactobacillus crispatus or Lactobacillus iners. Leptotrichia amnionii and Eggerthella sp. were the only two BV-associated bacteria (BVABs) significantly associated with each of the four Amsel’s criteria. Co-occurrence analysis revealed the presence of several sub-groups of BVABs suggesting metabolic co-dependencies. Greater abundance of several BVABs was observed in Black women without BV.Conclusions/SignificanceThe human vaginal bacterial biota is heterogeneous and marked by greater species richness and diversity in women with BV; no species is universally present. Different bacterial species have different associations with the four clinical criteria, which may account for discrepancies often observed between Amsel and Nugent (Gram stain) diagnostic criteria. Several BVABs exhibited race-dependent prevalence when analyzed in separate groups by BV status which may contribute to increased incidence of BV in Black women. Tools developed in this project can be used to study microbial ecology in diverse settings at high resolution.

Highlights

The microbiota of the human vagina can significantly impact the health of women, their fetuses and newborn infants [1,2,3]
We explored whether the presence of particular bacterial species or community types was different in Black women with and without Bacterial vaginosis (BV) when compared with White women
Of the 220 women studied by molecular evaluation of their microbiota, 98 (43%) had BV by Amsel’s criteria, and 117 (53%) by Gram stain (Table 1)

Summary

Introduction

The microbiota of the human vagina can significantly impact the health of women, their fetuses and newborn infants [1,2,3]. Bacterial vaginosis (BV) is a highly prevalent condition, affecting 29% of reproductive age women in the United States [4]. BV can be diagnosed using Amsel’s clinical criteria comprising a set of four characteristics including vaginal discharge, amine odor, elevated pH, and the presence of clue cells, wherein 3 of 4 criteria must be present to make a positive diagnosis [8]. Bacterial vaginosis (BV) is a common condition that is associated with numerous adverse health outcomes and is characterized by poorly understood changes in the vaginal microbiota.

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