Biotypes and virulence factors of Gardnerella vaginalis isolated from cases of bacterial vaginosis

Jeppu, Udayalaxmi; Bhat, Ganesh; Kotigadde, Subbannayya

doi:10.4103/0255-0857.81798

Cited by 19 publications

(16 citation statements)

References 10 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…G. vaginalis also produces haemolysin, liberating nutrients for the feeding of other anaerobic bacteria. It has been suggested that U. urealyticum is the most virulent of the mollicutes [115], expressing haemolytic activity and secretion of enzymes such as elastase, IgA protease (reducing mucosal immunity), phospholipase C, [126], and urease which hydrolyses urea to cytotoxic ammonia. Vaginal sloughing is facilitated by the production of sialidase, prolidase [117,121] and putrescine by G. vaginalis , Mobilincus [122] Megasphaera , [62], Bactroides fragilis [122] and Prevotella bivia [82,117].…”

Section: Resultsmentioning

confidence: 99%

Anaerobes and Bacterial Vaginosis in Pregnancy: Virulence Factors Contributing to Vaginal Colonisation

Africa

Nel

Stemmet

2014

IJERPH

View full text Add to dashboard Cite

The aetiology and pathogenesis of bacterial vaginosis (BV) is unclear but it appears to be associated with factors that disrupt the normal acidity of the vagina thus altering the equilibrium between the normal vaginal microbiota. BV has serious implications for female morbidity, including reports of pelvic inflammatory disease, adverse pregnancy outcomes, increased susceptibility to sexually transmitted infections and infertility. This paper reviewed new available information regarding possible factors contributing to the establishment of the BV vaginal biofilm, examined the proposed role of anaerobic microbial species recently detected by new culture-independent methods and discusses developments related to the effects of BV on human pregnancy. The literature search included Pubmed (NLM), LISTA (EBSCO), and Web of Science. Because of the complexity and diversity of population groups, diagnosis and methodology used, no meta-analysis was performed. Several anaerobic microbial species previously missed in the laboratory diagnosis of BV have been revealed while taking cognisance of newly proposed theories of infection, thereby improving our understanding and knowledge of the complex aetiology and pathogenesis of BV and its perceived role in adverse pregnancy outcomes.

show abstract

Section: Resultsmentioning

confidence: 99%

Anaerobes and Bacterial Vaginosis in Pregnancy: Virulence Factors Contributing to Vaginal Colonisation

Africa

Nel

Stemmet

2014

IJERPH

View full text Add to dashboard Cite

show abstract

“…Although numerous authors attempted to correlate differences between healthy and BV vaginal samples [54-57], no consensus was achieved, except that biofilm formation of G. vaginalis and a decrease in lactobacilli number could be considered as the initial stages in the pathogenesis of BV [10,58]. Swidsinski and colleagues already conducted an international follow-up study in which vaginal samples from several BV patients were analyzed by DNA-based FISH and a dense as well as active bacterial biofilm on vaginal mucosa was detected, primarily consisting of G. vaginalis [47].…”

Section: Discussionmentioning

confidence: 99%

Fluorescence in situ Hybridization method using Peptide Nucleic Acid probes for rapid detection of Lactobacillus and Gardnerella spp.

et al. 2013

View full text Add to dashboard Cite

BackgroundBacterial vaginosis (BV) is a common vaginal infection occurring in women of reproductive age. It is widely accepted that the microbial switch from normal microflora to BV is characterized by a decrease in vaginal colonization by Lactobacillus species together with an increase of Gardnerella vaginalis and other anaerobes. Our goal was to develop and optimize a novel Peptide Nucleic Acid (PNA) Fluorescence in situ Hybridization assay (PNA FISH) for the detection of Lactobacillus spp. and G. vaginalis in mixed samples.ResultsTherefore, we evaluated and validated two specific PNA probes by using 36 representative Lactobacillus strains, 22 representative G. vaginalis strains and 27 other taxonomically related or pathogenic bacterial strains commonly found in vaginal samples. The probes were also tested at different concentrations of G. vaginalis and Lactobacillus species in vitro, in the presence of a HeLa cell line. Specificity and sensitivity of the PNA probes were found to be 98.0% (95% confidence interval (CI), from 87.8 to 99.9%) and 100% (95% CI, from 88.0 to 100.0%), for Lactobacillus spp.; and 100% (95% CI, from 92.8 to 100%) and 100% (95% CI, from 81.5 to 100.0%) for G. vaginalis. Moreover, the probes were evaluated in mixed samples mimicking women with BV or normal vaginal microflora, demonstrating efficiency and applicability of our PNA FISH.ConclusionsThis quick method accurately detects Lactobacillus spp. and G. vaginalis species in mixed samples, thus enabling efficient evaluation of the two bacterial groups, most frequently encountered in the vagina.

show abstract

“…Phenotypic diversity within the G. vaginalis species has also been shown in relation to virulence factors, such as production of sialidase and vaginolysin, initial adhesion, cytotoxic effect, biofilm formation, susceptibility to antimicrobials, and the ability of G. vaginalis to displace lactobacilli adhered to HeLa cells [18–22]. Association of G. vaginalis biotypes with BV has been evaluated in a number of studies, but the results have been contradictory [11, 19, 20, 23–25]. Sialidase is utilized by some BV-associated bacteria, including G. vaginalis , for degradation and depletion of protective host mucus barriers [26, 27].…”

Section: Introductionmentioning

confidence: 99%

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

et al. 2019

View full text Add to dashboard Cite

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.

show abstract

Biotypes and virulence factors of Gardnerella vaginalis isolated from cases of bacterial vaginosis

Cited by 19 publications

References 10 publications

Anaerobes and Bacterial Vaginosis in Pregnancy: Virulence Factors Contributing to Vaginal Colonisation

Anaerobes and Bacterial Vaginosis in Pregnancy: Virulence Factors Contributing to Vaginal Colonisation

Fluorescence in situ Hybridization method using Peptide Nucleic Acid probes for rapid detection of Lactobacillus and Gardnerella spp.

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

Contact Info

Product

Resources

About