title: Assessment ofAtopobium vaginaeandGardnerella vaginalisconcentrations in a cohort of pregnant South African women.
abstract: The purpose of this cross-sectional study was to assessAtopobium vaginaeandGardnerella vaginalisconcentrations in pregnant women of different age groups, gestational age groups, vaginal flora categories and HIV status, and also to determine which DNA concentrations best discriminated between bacterial vaginosis (BV)-positive and non-BV categories.
  
  
  
  Self-collected vaginal swabs were obtained from 220 pregnant women attending an antenatal clinic in Pretoria, Gauteng, South Africa, from July 2012 to December 2012. BV was detected with the Nugent scoring system, andA. vaginaeandG. vaginalisDNA was quantified with a multiplex quantitative real-time PCR assay.
  
  
  
  Median concentrations ofA. vaginaeandG. vaginaliswere not significantly different among various age groups (A. vaginaep=0.98 andG. vaginalisp=0.18) or different trimesters (A. vaginaep=0.31 andG. vaginalisp=0.19), but differed significantly among the vaginal flora categories (A. vaginaep<0.001 andG. vaginalisp<0.001) and HIV status (A. vaginaep<0.001 andG. vaginalisp=0.004). The presence ofA. vaginae(OR=5.8; 95% CI 1.34 to 25.21 and p value=0.02) but not that ofG. vaginalis(OR=1.90; 95% CI 0.81 to 4.43 and p value=0.14) was associated with HIV infection. AnA. vaginaeDNA concentration of ≥107copies/mL together with a positiveG. vaginalisresult (≥100copies/mL) best discriminated between BV-positive (39/220) and non-BV categories (181/220) with a sensitivity of 85% (95% CI 0.70 to 0.94) and a specificity of 82% (95% CI 0.76 to 0.88).
  
  
  
  A. vaginaeandG. vaginaliswere present in high numbers and concentrations in this pregnant cohort. Threshold concentrations should be established for specific populations to ensure sensitive molecular assays for BV detection.
authors.affiliation: Department of Medical Microbiology, University of Pretoria, Pretoria, South Africa.
authors.forename: M J
authors.identifier: 0000-0002-9559-3317
authors.initials: MJ
authors.lastname: Redelinghuys
authors.affiliation: Department of Medical Microbiology, University of Pretoria, Pretoria, South Africa.|Department of Medical Microbiology, Tshwane Academic Division, National Health Laboratory Service, Pretoria, South Africa.
authors.forename: M M
authors.initials: MM
authors.lastname: Ehlers
authors.affiliation: Independent Researcher, Pretoria, Gauteng, South Africa.
authors.forename: J E
authors.initials: JE
authors.lastname: Bezuidenhoudt
authors.affiliation: Biostatistics Unit, University of Pretoria, Pretoria, South Africa.
authors.forename: P J
authors.initials: PJ
authors.lastname: Becker
authors.affiliation: Department of Medical Microbiology, University of Pretoria, Pretoria, South Africa.|Department of Medical Microbiology, Tshwane Academic Division, National Health Laboratory Service, Pretoria, South Africa.
authors.forename: M M
authors.initials: MM
authors.lastname: Kock
mesh_terms: D039903:Actinobacteria / Q000302:isolation & purification*; D000328:Adult; D000890:Anti-Infective Agents / Q000627:therapeutic use; D058491:Bacterial Load; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D005260:Female; D006194:Gardnerella vaginalis / Q000302:isolation & purification*; D006801:Humans; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*; D015995:Prevalence; D060888:Real-Time Polymerase Chain Reaction; D013019:South Africa / Q000453:epidemiology; D014621:Vagina / Q000382:microbiology; D016585:Vaginosis, Bacterial / Q000188:drug therapy / Q000453:epidemiology / Q000382:microbiology*
chemical_list: D000890:Anti-Infective Agents
keywords: BACTERIAL VAGINOSIS; PCR; PREGNANCY