Vaginal Microbiota Evaluation and Lactobacilli Quantification by qPCR in Pregnant and Non-pregnant Women: A Pilot Study

Abstract

Pregnancy outcomes and women's health are directly affected by vaginal microbiota. This microbiota consists of a dynamic ecosystem of various microbes in different ratios, which in healthy conditions protect the vaginal epithelium from infections. However, cases of vaginal infection are regularly diagnosed in women of reproductive age, contributing to more severe outcomes. Therefore, our main goal was to determine the prevalence of bacterial vaginosis (BV), aerobic vaginitis (AV), and vulvovaginal candidiasis (VVC) among Ecuadorian pregnant and non-pregnant women. A cross-sectional study was conducted among 217 women between 13 and 40 years old seeking primary healthcare in Carlos Andrade Marin Hospital (HCAM), Gynecological-Obstetric Hospital Isidro Ayora (HGOIA) and Center for Teaching Health Cipriana Dueñas during October 2018 to February 2019. The classical characterization of the vaginal microbiota was performed through microscopy by the Nugent criteria to evaluate the presence of BV, healthy and intermediate microbiota, by the criteria of Donders to determine the presence of AV and by the Marot-Leblond criteria to diagnose VVC. DNA extraction from vaginal samples and Polymerase Chain Reaction (PCR) analysis was performed to characterize the presence of Gardnerella spp., Mobiluncus mulieris, Escherichia coli, Enterococcus spp., and Lactobacillus spp. Finally, quantification of the lactobacilli was performed by quantitative real-time PCR (qPCR) for samples from women with normal vaginal microbiota and women with AV. Our results showed 52% of women with healthy microbiota, 7% with intermediate microbiota, and 41% with vaginal dysbiosis, comprising 27% with AV, 8% with BV and 4% with VVC and 2% with co-infections or co-dysbiosis. Additionally, a higher amount of lactobacilli were found in pregnant women when compared to non-pregnant women, while AV cases were characterized by a significant drop of Lactobacillus spp., more precisely, between 1E3 and 1E5 colony forming units (CFU)/ml. Pacha-Herrera et al. Vaginal Microbiota and Lactobacilli QuantificationFinally, women with normal vaginal microbiota showed an average load of lactobacilli between 1E6 and 1E7 CFU/ml. This pilot study showed no statistically significant differences between pregnant and non-pregnant women, pointing to the possibility to use lactobacilli quantification for the prevention of future vaginal infections.

Vaginal microbiota evaluation and prevalence of key pathogens in ecuadorian women: an epidemiologic analysis

“…The participants were informed by the associated physician how to collect their vulvovaginal swab sample. This sterile swab was brushed against the lateral vaginal walls to collect the fluid sample and was immediately placed in the transport media, stored at 4 °C and processed within the first 12 h. The analysis was carried out in the bacteriology laboratory of the Microbiology Institute at Universidad San Francisco de Quito (MI-USFQ), as previously realized in a study by Pacha-Herrera and colleagues 114 . The swab was used to prepare a vaginal smear for the microscopic examination of the vaginal microbiota, according to the Nugent and colleagues 26 .…”

Vulvovaginitis Prevalence Among Women in Gondar, Northwest Ethiopia: Special Emphasis on Aerobic Vaginitis Causing Bacterial Profile, Antimicrobial Susceptibility Pattern, and Associated Factors

“…9 Although data concerning the prevalence of AV in the general population is still scarce, there are studies done among pregnant and non-pregnant women. The prevalence of AV among pregnant women ranges from 2 to 51%, [10][11][12] and among non-pregnant women it ranges from 8.5 to 48.3%. 8,12 The paucity of studies relative to AV emphasizes the need for a better understanding of the epidemiology, etiology, and pathogenesis of AV in both pregnant and non-pregnant women, particularly in Africa, where AV has been poorly investigated.…”

Molecular genetic techniques in current biomedical research. Part II: PCR applications in diagnostics of human infectious diseases

“…Такого дисбаланса бывает достаточно для начала клинических проявлений и свидетельствует о необходимости медицинского вмешательства. В этом случае ПЦР-диагностика может дать исчерпывающее описание условно-патогенной и нормальной микрофлоры [13,14].…”