Skip to main page content
U.S. flag

An official website of the United States government

Dot gov

The .gov means it’s official.
Federal government websites often end in .gov or .mil. Before sharing sensitive information, make sure you’re on a federal government site.

Https

The site is secure.
The https:// ensures that you are connecting to the official website and that any information you provide is encrypted and transmitted securely.

Access keys NCBI Homepage MyNCBI Homepage Main Content Main Navigation
. 2019 Feb;23(1):139-147.
doi: 10.1007/s40291-019-00382-5.

Quantitation of all Four Gardnerella vaginalis Clades Detects Abnormal Vaginal Microbiota Characteristic of Bacterial Vaginosis More Accurately than Putative G. vaginalis Sialidase A Gene Count

Elena Shipitsyna  1 , Anna Krysanova  1 , Guzel Khayrullina  2 , Kira Shalepo  1 , Alevtina Savicheva  1 , Alexander Guschin  2 , Magnus Unemo  3
Affiliations

Quantitation of all Four Gardnerella vaginalis Clades Detects Abnormal Vaginal Microbiota Characteristic of Bacterial Vaginosis More Accurately than Putative G. vaginalis Sialidase A Gene Count

Elena Shipitsyna et al. Mol Diagn Ther. 2019 Feb.

Abstract

Background: Bacterial vaginosis (BV) is a vaginal disorder characterized by a depletion of the normal lactobacillus-dominant microbiota and overgrowth of mainly anaerobic bacteria.

Objectives: The study aimed to evaluate the distribution and abundance of the Gardnerella vaginalis clades and sialidase A gene in vaginal samples from Russian women, and investigate if the G. vaginalis sialidase A gene count detects an abnormal vaginal microbiota characteristic of BV more accurately than G. vaginalis load.

Methods: Vaginal samples from 299 non-pregnant patients of gynecological clinics were examined using Nugent scores and G. vaginalis clade and sialidase A gene quantitative real-time polymerase chain reactions (PCRs). Discriminatory power for BV microbiota was evaluated with receiver operating characteristic (ROC) analysis.

Results: The vaginal microbiota was characterized by Nugent scores as normal, intermediate, and BV microbiota in 162, 58, and 79 women, respectively. G. vaginalis clades 1, 2, 3, 4, and the sialidase A gene were detected in 56% (51-62%), 40% (34-45%), 20% (16-25%), 94% (91-96%), and 70% (64-75%) of vaginal samples, respectively. The frequency and abundance of clades 1, 2, 4, and the sialidase A gene as well as clade multiplicity were significantly associated with abnormal microbiota. The sialidase A gene was present in all multi-clade samples, in all single-clade samples comprising clades 1, 2, and 3, and in four of 84 (5% [2-12%]) samples comprising clade 4 only. Total G. vaginalis load showed significantly higher discriminatory power for abnormal microbiota than sialidase A gene count (areas under ROC curves 0.933 vs. 0.881; p = 0.0306).

Conclusions: Quantifying all four G. vaginalis clades discriminates between BV microbiota and normal microbiota more accurately than measuring G. vaginalis sialidase A gene. Clade 4 is strongly associated with BV microbiota, despite most clade 4 strains lacking the sialidase A gene.

PubMed Disclaimer

Conflict of interest statement

Conflict of interest

Elena Shipitsyna, Anna Krysanova, Guzel Khayrullina, Kira Shalepo, Alevtina Savicheva, Alexander Guschin, and Magnus Unemo declare that they have no conflicts of interest that are directly relevant to the content of this study.

Ethical approval

The study was approved by the Ethical Committee at the D.O. Ott Research Institute of Obstetrics, Gynaecology and Reproductology, St Petersburg (approval number 73/2015).

Informed consent

Informed consent was obtained from all individual participants included in the study.

Figures

Fig. 1
Fig. 1
Single versus multiple Gardnerella vaginalis clades in women with normal microbiota, intermediate microbiota, and abnormal vaginal microbiota characteristic of bacterial vaginosis (BV)
Fig. 2
Fig. 2
Areas under the receiver operating characteristic curves (values provided in parentheses) for the Gardnerella vaginalis clades and sialidase A gene. FPF false positive fraction, TPF true positive fraction
See this image and copyright information in PMC

References

    1. Koumans EH, Sternberg M, Bruce C, McQuillan G, Kendrick J, Sutton M, et al. The prevalence of bacterial vaginosis in the United States, 2001–2004; associations with symptoms, sexual behaviors, and reproductive health. Sex Transm Dis. 2007;34:864–869. doi: 10.1097/OLQ.0b013e318074e565. - DOI - PubMed
    1. Taylor BD, Darville T, Haggerty CL. Does bacterial vaginosis cause pelvic inflammatory disease? Sex Transm Dis. 2013;40:117–122. doi: 10.1097/OLQ.0b013e31827c5a5b. - DOI - PubMed
    1. Allsworth JE, Peipert JF. Severity of bacterial vaginosis and the risk of sexually transmitted infection. Am J Obstet Gynecol. 2011;205(113):e1–e6. - PMC - PubMed
    1. Donati L, Di Vico A, Nucci M, Quagliozzi L, Spagnuolo T, Labianca A, et al. Vaginal microbial flora and outcome of pregnancy. Arch Gynecol Obstet. 2010;281:589–600. doi: 10.1007/s00404-009-1318-3. - DOI - PubMed
    1. Denney JM, Culhane JF. Bacterial vaginosis: a problematic infection from both a perinatal and neonatal perspective. Semin Fetal Neonatal Med. 2009;14:200–203. doi: 10.1016/j.siny.2009.01.008. - DOI - PubMed

Publication types