Diagnosis of bacterial vaginosis: need for validation of microscopic image area used for scoring bacterial morphotypes

The association between symptom or microscopy based diagnosis of bacterial vaginosis (BV) and response to treatment in women with recurrent BV

BACKGROUND

Bacterial vaginosis (BV) is a common condition, yet accurate diagnosis remains a challenge. We explored symptom and microscopy-based diagnosis of BV and assessed the influence of these diagnostic approaches on treatment response.

METHODS

BV diagnosis based on patient-reported symptoms, and vaginal swab gram stain microscopy at local laboratories and a central laboratory were compared for women recruited into the VITA trial in England. Multivariable analysis was used to assess the association between the method of diagnosis and symptom resolution 2 weeks after metronidazole treatment.

RESULTS

517 women presenting with vaginal discharge (470/517 [91%]) and/or malodour (440/517 [85%]) were included. The accuracy of patients' vaginal symptoms compared to local laboratory microscopy for BV diagnosis were -discharge, sensitivity 90% and specificity 5%; malodour, sensitivity 84% and specificity 12%, and compared to a central laboratory diagnosis were -discharge, sensitivity 91% and specificity 8%; malodour, sensitivity 88% and specificity 18%. 143/204 (70%) participants reported symptom resolution after treatment and this was associated with a positive baseline local laboratory diagnosis (adjusted relative risk-aRR 1.64 [1.02 to 2.64]), but not with a positive central laboratory diagnosis (aRR 1.14 [0.95 to 1.37]). Symptom resolution occurred in 75% (83/111) of women who were symptom positive/central laboratory BV positive compared to 65% (58/89) who were symptom positive/microscopy negative.

CONCLUSION

Symptoms correlated poorly with microscopy-based BV diagnosis but two-thirds of women with a symptom positive/microscopy negative diagnosis experienced symptom resolution following metronidazole treatment. Further studies are needed to determine the optimal investigation and treatment for microscopy-negative women with typical BV symptoms.

The Vaginal Microbiome: II. Vaginal Dysbiotic Conditions

OBJECTIVE

This series of articles, titled The Vaginal Microbiome (VMB), written on behalf of the International Society for the Study of Vulvovaginal Disease, aims to summarize the recent findings and understanding of the vaginal bacterial microbiota, mainly regarding areas relevant to clinicians specializing in vulvovaginal disorders.

MATERIALS AND METHODS

A search of PubMed database was performed, using the search terms "vaginal microbiome" with "dysbiosis," "bacterial vaginosis," "cytolytic vaginosis," "desquamative inflammatory vaginitis," and "aerobic vaginitis." Full article texts were reviewed. Reference lists were screened for additional articles.

RESULTS

The second article in this series focuses on vaginal dysbiotic conditions. Dysbiosis is a term describing imbalances in bacterial communities. Given that lactobacillus-dominated microbiota are thought to be the most optimal, vaginal dysbiosis is usually considered as lactobacilli-depleted VMB. Bacterial vaginosis (BV), the most common vaginal dysbiotic condition, is a polymicrobial disorder, considered the leading cause for vaginal discharge in women worldwide. In addition, we review the VMB in other vaginal conditions associated with lactobacilli depletion: desquamative inflammatory vaginitis and aerobic vaginitis. We also discuss the controversial diagnosis of cytolytic vaginosis, related with lactobacilli overgrowth.

CONCLUSIONS

Bacterial vaginosis displays complex microbiology. The heterogeneity and diversity within the genus Gardnerella may impact the progression of BV. Bacterial biofilms may contribute to the etiology and persistence of BV, and various bacteria may affect its clinical presentation and pathogenicity. Lack of lactobacilli is not always accompanied by an overgrowth of anaerobes.

Diagnosis of bacterial vaginosis: Comparison of Nugent´s and novel microscopic method

Background/Aim. Bacterial vaginosis (BV) is a common cause of vaginal discomfort in women. The aim of this study was to compare Nugent?s scoring system and novel microscopy method, introduced in our laboratory and used in BV diagnosis. Methods. This study included 705 pregnant and asymptomatic women between 24 and 28 weeks of pregnancy. The degree of agreement between methods was determined by the kappa (?) index. The sensitivity, specificity, positive and negative predictive value of the novel microscopy method was compared to Nugent?s score as standard. Results. Based on the scoring system of both methods, Nugent?s and novel microscopy method, BV was diagnosed in 21% and 25% of women, respectively. Despite the disparities among diagnostic criteria, which mainly concerned classification of intermediary samples, the degree of agreement between categories, determined by ? index, was satisfactory: Nugent?s vs. novel microscopy method (? = 0.68; good agreement), and Nugent?s vs. novel microscopy method without intermediary results (? = 0.83; very good agreement). We also demonstrated that compared to Nugent?s method, as the golden standard, the novel microscopy method had high sensitivity and specificity (ranging from 75%?99.3%) and positive and negative predictive values (ranging from 88.8%?99.5%). Our method is based on a relative number of bacterial morphotypes, either rod forms (? 1.5 ?m, lactobacilli) or non-rod forms (< 1.5 ?m, bacterial vaginosis associated bacteria) under 200? magnification, which extends the surface of examined preparation, but without prolongation of observer?s working time. Conclusion. The novel microscopy method in diagnosing BV corresponded well with Nugent?s scoring system which allows it to be an alternative method in diagnosing BV. Further-more, the novel microscopy method is based on a relative number of bacterial morphotypes that appeared to be flexible and can be reorganized in the way to categorize findings into only two groups: normal and BV, which makes it comparable to dichotomous Amsel?s clinical criterion.

Finding a Balance in the Vaginal Microbiome: How Do We Treat and Prevent the Occurrence of Bacterial Vaginosis?

Bacterial vaginosis (BV) has been reported in one-third of women worldwide at different life stages, due to the complex balance in the ecology of the vaginal microbiota. It is a common cause of abnormal vaginal discharge and is associated with other health issues. Since the first description of anaerobic microbes associated with BV like Gardnerella vaginalis in the 1950s, researchers have stepped up the game by incorporating advanced molecular tools to monitor and evaluate the extent of dysbiosis within the vaginal microbiome, particularly on how specific microbial population changes compared to a healthy state. Moreover, treatment failure and BV recurrence rate remain high despite the standard antibiotic treatment. Consequently, researchers have been probing into alternative or adjunct treatments, including probiotics or even vaginal microbiota transplants, to ensure successful treatment outcomes and reduce the colonization by pathogenic microbes of the female reproductive tract. The current review summarizes the latest findings in probiotics use for BV and explores the potential of vaginal microbiota transplants in restoring vaginal health.

The International Society for the Study of Vulvovaginal Disease Vaginal Wet Mount Microscopy Guidelines: How to Perform, Applications, and Interpretation

OBJECTIVES

The aims of the study were to assess the available literature concerning the indications, performance, technique, and classification of wet mount microscopy (WMM) and to establish evidence-based recommendations.

METHODS

Literature review from the main scientific databases was performed by the ad hoc "Vaginitis and Microbiome Committee" of the International Society for the Study of Vulvovaginal Disease. The document was approved by the executive council and membership of the International Society for the Study of Vulvovaginal Disease.

RESULTS

Available data are limited and usually of low level of evidence. Nevertheless, it shows that WMM is capable of reducing misdiagnosis, overtreatment, and undertreatment of vaginal conditions. It has an excellent performance for the diagnosis of bacterial vaginosis and variable performance for trichomoniasis and candidiasis. It is the gold standard for aerobic vaginitis/desquamative inflammatory vaginitis. Currently, there is no recommendation to use WMM in the screening of asymptomatic women.The use of phase contrast is recommended to improve performance and reproducibility. Sampling location, devices, and technique have an impact on the results.Available scoring and classification scores have significant limitations.

CONCLUSIONS

Wet mount microscopy is a point-of-care, inexpensive, and fast technique that, with practice, can be mastered by office clinicians. It should be considered a basic skill in the curricula of gynecology and obstetrics residencies. Recommendations are provided on sampling, reading, and scoring.

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

Vaginal infection is a gynecological problem in women of reproductive age with multiple health outcomes. The most common forms of infection include bacterial vaginosis (BV), vulvovaginal candidiasis (VC), and aerobic vaginitis (AV). Our main goals were to evaluate different types of vaginal infections in Ecuadorian women in a large urban area (Quito) and to characterize the vaginal microbiota colonization by opportunistic species. We collected vaginal swabs and epidemiological surveys from 414 women from June 2016 to July of 2017. We analyzed vaginal samples for the presence of any vaginal infection. The microbiological examination was done through Gram-stain, wet mount smears, and polymerase chain reaction (PCR) assays using primers for target genes, such as 16S rRNA (Atopobium vaginae, Mobiluncus mulieris, and Gardnerella species), ddl (Enterococcus faecalis), adk (Escherichia coli) and KER1 (Candida albicans) genes. Most women showed a healthy vaginal microbiota (66.7%). Nearly one-tenth (10.4%) of the participants had intermediate microbiota, and the remaining women (22.9%) had a single vaginal infection (BV, AV, or VC) or coinfections. From the 95 participants that had an infection, AV was the main diagnosed vaginal infection (51.6%), followed by BV (24.2%) and finally VC (7.4%). The remaining women (16.8%) showed coinfections, being BV and AV the most common coinfection. Using univariable logistic regression analyses we found an increased odds of healthy microbiota in women with a sexual partner (P = 0.02, OR = 1.64). Also, women in a free union relationship (P = 0.000, OR = 16.65) had an increased odds of having coinfections. On the other hand, the use of birth control (condom OR = 0.388 or other contraceptive method OR = 0.363) was associated with significantly lower odds of intermediate microbiota (P ≤ 0.05). We found no statistically significant differences between women with infection and a particular group age. Using multivariate logistic regression analyses we initially found an increased odds of having BV in women with M. mulieris (P = 0.020, OR = 4.98) and Gardnerella species (P = 0.010, OR = 4.16). Women with E. coli showed an increased odds of having AV (P = 0.009, OR = 2.81). The presence of C. albicans in women showed an increased odds of having VC (P = 0.007, OR = 17.94). Finally, women with M. mulieris showed a reverse odds of having healthy microbiota (P = 0.008, OR = 0.06). We found no statistically significant differences between women with symptomatic and asymptomatic infections or the presence of Enterococcus faecalis. We found using logistic regression analyses that M. mulieris was the most prevalent opportunistic pathogen among women with vaginal infection. Further studies should evaluate the possibility to use M. mulieris as a potential key predictor for vaginal infections.

Probiotics for the Treatment of Bacterial Vaginosis: A Meta-Analysis

Background: The effect of probiotic therapy on bacterial vaginosis (BV) is controversial. We conducted a meta-analysis of the efficacy and safety associated with probiotic treatment for BV. Methods: We searched multiple databases covering up to 1 March 2018. Studies published as blinded randomized controlled trials (RCTs), comparing treatment using probiotic versus active or placebo control in BV patients were included, with at least one-month follow-up. Random effects model and trial sequential analysis (TSA) were applied. Results: Ten studies (n = 2321) were included. Compared with placebo, the probiotics-only therapy resulted in a beneficial outcome both in clinical cure rate at the 30th day (risk ratio, RR = 2.57; 95% confidential interval, 95% CI: 1.96 to 3.37), and Nugent score (mean difference, MD = −2.71; 95% CI: −3.41 to −2.00). This effect decreased but remained significant after eight weeks. Probiotics-post-antibiotics therapy had a decreased effect only for a short term and possibly among studies with a mostly black study population. No extra adverse events were observed. The TSA suggested a larger sample size for effective evaluation of the probiotics as a supplementary remedy. Conclusions: Probiotic regimes are safe and may exhibit a short-term and long-term beneficial effect for BV treatment. The ethnic-specific result for the probiotic used after antibiotics is worthy of further study.

Evaluation of interobserver reliability of Nugent score for diagnosis of bacterial vaginosis

Background

Vaginal discharge is the commonly narrated compliant of the female attendees of sexually transmitted infection clinic, among which bacterial vaginosis (BV) is responsible for one-third of the visits. BV is often diagnosed clinically which warrants laboratory confirmation.

Aims

The study aims to detect the reliability of the Nugent scoring system between observers for the diagnosis of BV.

Materials and Methods

This is a prospective study including 177 high vaginal swabs. The gram-stained smears were examined by three independent microbiologists, and the Nugent scoring was performed. Statistical analysis was performed using IBM-SPSS version-22 statistical package for kappa value.

Results

Concordant results were seen in 64.03% of smears, discordant results were given in 4.51% of smears, and partial agreement was observed in 31.63% of smears.

Conclusion

Interobserver reliability is good for the Nugent score. The Nugent score is a simple and reliable method for the diagnosis of BV that can be adapted even in the resource poor settings.

Association of high-risk sexual behaviour with diversity of the vaginal microbiota and abundance of Lactobacillus

Objective

To compare the vaginal microbiota of women engaged in high-risk sexual behaviour (sex work) with women who are not engaged in high-risk sexual behaviour. Diverse vaginal microbiota, low in Lactobacillus species, like those in bacterial vaginosis (BV), are associated with increased prevalence of sexually transmitted infections (STIs) and human immunodeficiency virus (HIV) acquisition. Although high-risk sexual behaviour increases risk for STIs, the vaginal microbiota of sex workers is understudied.

Methods

A retrospective cross-sectional study was conducted comparing vaginal microbiota of women who are not engaged in sex work (non-sex worker controls, NSW, N = 19) and women engaged in sex work (female sex workers, FSW, N = 48), using Illumina sequencing (16S rRNA, V3 region).

Results

Bacterial richness and diversity were significantly less in controls, than FSW. Controls were more likely to have Lactobacillus as the most abundant genus (58% vs. 17%; P = 0.002) and composition of their vaginal microbiota differed from FSW (PERMANOVA, P = 0.001). Six microbiota clusters were detected, including a high diversity cluster with three sub-clusters, and 55% of women with low Nugent Scores fell within this cluster. High diversity was observed by 16S sequencing in FSW, regardless of Nugent Scores, suggesting that Nugent Score may not be capable of capturing the diversity present in the FSW vaginal microbiota.

Conclusions

High-risk sexual behaviour is associated with diversity of the vaginal microbiota and lack of Lactobacillus. These factors could contribute to increased risk of STIs and HIV in women engaged in high-risk sexual behaviour.

Bacterial morphotype grading for periodontal disease assessment

Background:

Listgarten and Hellden (1978) used darkfield microscopy of wet mounts to differentiate between healthy and periodontally diseased sites in the mouth by expressing the different bacterial morphotypes observed as a percentage of the total number of bacteria counted. This method of periodontal disease assessment gained favour as a diagnostic tool but presented with the limitation of immediate examination to determine the number of motile rods present and an inability to distinguish between gingivitis and periodontitis. Grading of bacterial morphotypes into several distinct categories of health or disease (Ison and Hay, 2002), simplified the scoring system of Gram-stained smears for the diagnosis of bacterial vaginosis (Nugent et al. 1991). The application of a similar grading system using stained smears rather than wet mounts could be advantageous to the diagnosis of periodontal disease.

Objectives/aims:

This study tested the hypothesis that stained smears of dental plaque collected from the gingival crevice of individuals with varying probing pocket depths (PD) may provide a grading system for periodontal disease assessment.

Materials and methods:

Subgingival plaque samples were collected from 49 patients, stained with a silver stain and the proportions of each bacterial morphotype graded relative to their respective PD measurements.

Results:

This technique allowed for a grading system of I–IV, with grade I indicating health and grade IV indicating severe periodontal disease.

Discussion:

Stained smear examination eliminates the time restriction for motile rod enumeration and allows for storage of smears for future reference.

Conclusion:

Standardization of the microscopic areas to be evaluated or examined will facilitate the agreement of cut-off values for the diagnosis of periodontal disease.

Utility of microbiological profile of symptomatic vaginal discharge in rural women of reproductive age group

INTRODUCTION

Symptomatic vaginal discharge is the most frequent symptom in women of reproductive age group. Owing to social stigma majority of affected women hesitate to seek medical consultation. Therefore the actual incidence of vaginal discharge is much more than what is reported. The aim of the study is to determine the microbiological profile of symptomatic vaginal discharge in rural area and its utility in the management of genital tract infection.

MATERIALS AND METHODS

This was a descriptive type of observational study, conducted in sexually active women of reproductive age group (18-45 years) attending the OPD/IPD of Obstetrics and Gynaecology Department of National Institute of Medical Sciences, Shobhanagar, Jaipur (Rajasthan), over a period of 18 months from June 2012 to December 2013. Hundred sexually active non pregnant women of reproductive age group (18-45 years) were included in the study. After taking consent general physical examination along with pelvic examination was performed. Two high vaginal swabs and blood sample were collected for various tests. Hanging drop preparation was immediately made. This was followed by gram staining and culture. Chlamydia trachomatis IgM antibody was detected by ELISA method.

RESULTS

Out of 100 women with symptomatic vaginal discharge, specific diagnosis was obtained in 89% of cases whereas no specific aetiology was found in 11% cases. Mean age was 32.60 years. Fifty-three percent patient had Bacterial vaginosis, candidiasis was found in 14% cases, 16% had Chlamydia trachomatis infection while Trichomonas vaginalis infection was detected in 6% cases. Homogenous discharge was most prevalent (52%), followed by mucopurulant discharge in 23% of women.

CONCLUSION

Patient with symptomatic vaginal discharge need to be actively managed with appropriate antimicrobial agents. Judicious management may be helpful in prevention of HIV, HPV, CIN and post infection sequelae.

Inkwari: an emerging high-risk place potentiating hiv spread among young adults in a hyper-endemic South African setting

Young adults in South Africa are at the epicenter of the HIV epidemic. The prevalence of HIV among young people in the province of KwaZulu-Natal (KZN) is particularly high. This study characterizes inkwari (Zulu word for raves or weekend-long parties) in eThekwini District, KZN and explored how these place-based dynamics shape the risk environment for the young adult attendees. In 2011, 13 qualitative interviews were conducted with men and women between 18 and 30 years-old who reported unprotected sex with at least one casual partner in the prior 3 months and attended an inkwari in the same time period. Interviews were analyzed using qualitative content analysis. Nine key informant interviews helped to triangulate these data. Five women and eight men were interviewed and the mean age was 25 years (SD 3.24). Ten reported meeting a sexual partner at an inkwari. Inkwari were characterized as sexualized settings with limited adult supervision. Participants attended inkwari to socialize with peers, use drugs and alcohol, and meet sexual partners. Sexual and physical violence also occurred at inkwari. Given the convergence of social, sexual, and substance-using networks at inkwari, further inquiry is needed to determine how this place may potentiate HIV transmission risk in an endemic setting.

Relationship of selected bacterial vaginosis-associated bacteria to Nugent score bacterial vaginosis among urban women early in pregnancy

Among urban, primarily African American pregnant women, 74% were identified with Nugent score bacterial vaginosis (BV). All BV-associated bacteria were more prevalent among women with Nugent score BV. Bacterial vaginosis-associated bacteria 3 (BVAB3) had the highest positive predictive value, whereas Gardnerella vaginalis and Atopobium spp. had the highest sensitivity. Atopobium spp. levels had the most significant area under the curve.

Comparison of Hay's criteria with Nugent's scoring system for diagnosis of bacterial vaginosis

Although Nugent's criterion is considered as the gold standard for the diagnosis of bacterial vaginosis (BV), the method requires an experienced slide reader and considerable time and skill. In this study, we compared the method of Hay and Ison with Nugent's scoring criteria. Vaginal specimens were collected from a total of 213 women, presenting with or without the symptoms of vaginitis. Diagnosis of BV was done using Nugent' and Hay's method. Sensitivity, specificity, and predictive values for positive and negative test were calculated for Hay's method using Nugent's method as the gold standard. We diagnosed 70 cases (32.86%) of BV by Nugent's method and 87 (40.85%) cases by the Hay's method. Sensitivity, specificity, predictive value of positive result, predictive value of negative result, and Kappa value when evaluating Hay's criteria using Nugent's criteria as the gold standard were ≥97.2%, ≥88.1%, ≥80.4%, ≥97.1%, and ≥0.830, respectively, when Hay's grade II and/or Nugent's intermediate score were considered either as negative or positive or excluded. Using Nugent score for the intermediate group is the most difficult. Hay's method shows good agreement with the gold standard method of Nugent et al. and can be used as an alternative to Nugent's criteria in busy tertiary care hospitals.

Efficacy of methods used for the diagnosis of bacterial vaginosis

INTRODUCTION

Bacterial vaginosis (BV) has been associated with pelvic inflammatory disease, adverse pregnancy outcomes, increased susceptibility to sexually transmitted infections and infertility. Diagnosis of BV should be rapid, reliable and safe. This is especially vital in pregnant women where intervention may be necessary for the well-being of both the mother and the foetus.

AREAS COVERED

This paper consulted PUBMED, LISTA and Web of Science for point-of-care and laboratory-based tests commonly used for the diagnosis and management of BV in pregnant women. An overview of strengths and weaknesses of the methods used may partially explain why treatment plans have failed. Differences in sampling and detection methods, time of gestation, inter-examiner variability and interpretation of data, and the use of different reference tests, amongst many other factors, complicated a meta-analysis of the data.

EXPERT OPINION

Inconsistencies found in clinical and laboratory detection methods used for the monitoring of treatment have a direct impact on success rates. With current advances in technology, the diagnosis of BV is taking on a new perspective. New information implicating specific vaginal biofilms in adverse pregnancy outcomes through the application of advanced technology promises to change the way we view the aetiology, diagnosis and management of BV.

Exploring a road map to counter misconceptions about the cervicovaginal microbiome and disease

Urogenital diseases, especially infection and cancer, are major causes of death and morbidity in females. Yet, millions of women in the developing world have no access to basic urogynecological care, and the diagnosis and treatment of widespread aberrant bacterial conditions (bacterial vaginosis [BV] and aerobic vaginitis [AV]) remain suboptimal the world over. Samples from women living in resource-disadvantaged and developed countries have been analyzed by high-throughput sequencing to reveal the diversity of bacteria in the vagina, how rapidly the bacterial population fluctuates over time, and how rapidly the switch occurs between healthy and aberrant conditions. Unfortunately, clinical diagnostic methods are inefficient and too often outdated therapies are administered. The net result is suboptimal care and recurrent disease that adversely affects the quality of life. This viewpoint outlines a scientific and translational road map designed to improve the cervicovaginal health and treatment of disease. This comprises (1) improving education of women and physicians on the vaginal microbiota; (2) having agencies target funding for research to improve diagnosis and test new therapies; and (3) making sure that new approaches are accessible in developing countries, empowering to women, and are acceptable and appropriate for different populations.

A venue-based approach to reaching MSM, IDUs and the general population with VCT: a three study site in Kenya

A venue-based HIV prevention study which included Voluntary Counseling and Testing (VCT) was conducted in three diverse areas of Kenya-Malindi, Nanyuki and Rachounyo. Aims of the study were to: (1) assess the acceptability of VCT for the general population, men who have sex with men (MSM), and injecting drug users (IDUs) within the context of a venue-based approach; (2) determine if there were differences between those agreeing and not agreeing to testing; and (3) study factors associated with being HIV positive. Approximately 98% of IDUs and 97% of MSM agreed to VCT, providing evidence that populations with little access to services and whose behaviors are stigmatized and often considered illegal in their countries can be reached with needed HIV prevention services. Acceptability of VCT in the general population ranged from 60% in Malindi to 48% in Nanyuki. There were a few significant differences between those accepting and declining testing. Notably in Rachuonyo and Malindi those reporting multiple partners were more likely to accept testing. There was also evidence that riskier sexual behavior was associated with being HIV positive for both men in Rachounyo and women in Malindi. Overall HIV prevalence was higher among the individuals in this study compared to individuals sampled in the 2008-2009 Kenya Demographic and Health Survey, indicating the method is an appropriate means to reach the highest risk individuals including stigmatized populations.

Prevalence of bacterial vaginosis and its risk factors in HIV/AIDS patients with abnormal vaginal discharge

OBJECTIVE

To determine the prevalence of bacterial vaginosis in the HIV/AIDS patients of primary health care clinics in Jos Plateau state, Nigeria.

METHODS

Female genital swabs were collected from primary health care centers, Jos and analyzed by microscopy, culture, etc. in Jos University Teaching Hospital from December 2006 to December 2007. Data on epidemiologic indices were collected, using structured interviewer-administered questionnaires.

RESULTS

The incidence of bacterial vaginosis in the study was 28% (n=196/700). Among the HIV/AIDS group, the bacterial vaginosis incidence was 36% (n=126/350), while in the control (non-HIV patients) group, the rate was 20% (70/350) with a statistically significant difference at 95 percent confidence level (P<0.05). HIV/AIDS and non-HIV (control) patients contributed 64% (n=126/196) and 36% (n=70/196), respectively. The risks to bacterial vaginosis included vaginal douching with disinfectant/detergent constituted (60%), poor use of condom 40%, a median age of 26 years, and a median number of 3 sex partners per week.

CONCLUSIONS

There was a significant statistical difference in prevalence of bacterial vaginosis between the HIV/AIDS group and non-HIV(control) group of patients in the study. Risk behaviors that promote the incidence of bacterial vaginosis should be especially paid attention.

Self-collected vaginal swabs for the quantitative real-time polymerase chain reaction assay of Atopobium vaginae and Gardnerella vaginalis and the diagnosis of bacterial vaginosis

The aim of this study was to assess the feasibility of using self-collected vaginal specimens for the quantitative real-time polymerase chain reaction (qPCR) assays of bacterial vaginosis (BV)-associated bacteria versus practitioner-collected swabs. A cross-sectional study included 190 pregnant women enrolled before 20 weeks' gestation from September 2008 to November 2009. Self- and practitioner-collected swabs were taken during the same prenatal visit for each woman, qPCR assays performed for each, and the results compared. The quantification of the human albumin gene was used as an internal control to ensure sampling quality and accurate comparisons. The level of agreement of the qPCR assays for each microorganism was calculated with the Spearman product moment correlation coefficient and the kappa statistic. In all, 370 vaginal samples (185 self- and 185 practitioner-collected swabs) had a narrow range of values for the number of albumin gene copies and a significant correlation coefficient (Spearman's rho = 0.532; p < 0.001). The agreement between both sampling methods was excellent (Spearman's rho was 0.748 for Atopobium vaginae, 0.918 for Lactobacillus species, 0.940 for Gardnerella vaginalis; p < 0.001), especially for high concentrations of A. vaginae (≥10(8) copies/mL; kappa value = 0.973; p < 0.001) and G. vaginalis (≥10(9) copies/mL; kappa value = 0.903; p < 0.001). This study demonstrates the validity and reliability of self- versus practitioner-collected swabs for the molecular quantification of Lactobacillus species, G. vaginalis, and A. vaginae.

Diagnostic accuracy of quantitative real-time PCR assay versus clinical and Gram stain identification of bacterial vaginosis

The purpose of this investigation was to determine the diagnostic accuracy of quantitative real-time polymerase chain reaction (PCR) assay in diagnosing bacterial vaginosis versus the standard methods, the Amsel criteria and the Nugent score. The Amsel criteria, the Nugent score, and results from the molecular tool were obtained independently from vaginal samples of 163 pregnant women who reported abnormal vaginal symptoms before 20 weeks gestation. To determine the performance of the molecular tool, we calculated the kappa value, sensitivity, specificity, and positive and negative predictive values. Either or both of the Amsel criteria (≥3 criteria) and the Nugent score (score ≥7) indicated that 25 women (15%) had bacterial vaginosis, and the remaining 138 women did not. DNA levels of Gardnerella vaginalis or Atopobium vaginae exceeded 10(9) copies/mL or 10(8) copies/mL, respectively, in 34 (21%) of the 163 samples. Complete agreement between both reference methods and high concentrations of G. vaginalis and A. vaginae was found in 94.5% of women (154/163 samples, kappa value = 0.81, 95% confidence interval 0.70-0.81). The nine samples with discordant results were categorized as intermediate flora by the Nugent score. The molecular tool predicted bacterial vaginosis with a sensitivity of 100%, a specificity of 93%, a positive predictive value of 73%, and a negative predictive value of 100%. The quantitative real-time PCR assay shows excellent agreement with the results of both reference methods for the diagnosis of bacterial vaginosis.

Bacterial vaginosis: an update on diagnosis and treatment

Bacterial vaginosis is the most common cause of vaginal complaints. Bacterial vaginosis is further associated with a sizeable burden of infectious complications. Diagnosis relies on standardized clinical criteria or on scoring bacterial cell morphotypes on a Gram-stained vaginal smear. A few point-of-care tests have not gained footage in clinical practice, but molecular diagnosis is now pending. Treatment remains cumbersome and clinicians are currently rather poorly armed to treat bacterial vaginosis in the long run. As an adjuvant to standard treatment with antibiotics, alternative treatments with antiseptics and disinfectants, vaginal-acidifying and -buffering agents, and probiotics hold some promise for long-term prevention.

Molecular quantification of Gardnerella vaginalis and Atopobium vaginae loads to predict bacterial vaginosis

BACKGROUND

Bacterial vaginosis (BV) is a poorly detected public health problem that is associated with preterm delivery and for which no reliable diagnostic tool exists.

METHODS

Molecular analysis of 231 vaginal samples, classified by Gram stain-based Nugent score, was used to propose molecular criteria for BV; these criteria were prospectively applied to 56 new samples. A quantitative molecular tool targeting 8 BV-related microorganisms and a human gene was developed using a specific real-time polymerase chain reaction assay and serial dilutions of a plasmid suspension. The targeted microorganisms were Gardnerella vaginalis, Lactobacillus species, Mobiluncus curtisii, Mobiluncus mulieris, and Candida albicans (which can be identified by Gram staining), as well as Atopobium vaginae, Mycoplasma hominis, and Ureaplasma urealyticum (which cannot be detected by Gram staining).

RESULTS

With use of the Nugent score, 167 samples were classified as normal, 20 were classified as BV, and 44 were classified as intermediate. Except for U. urealyticum, M. mulieris, and Lactobacillus species, DNA of the tested bacteria was detected more frequently in samples demonstrating BV, but the predictive value of such detection was low. The molecular quantification of A. vaginae (DNA level, > or = 10(8) copies/mL) and G. vaginalis (DNA level, > or = 10(9) copies/mL) had the highest predictive value for the diagnosis of BV, with excellent sensitivity (95%), specificity (99%), and positive (95%) and negative (99%) predictive values; 25 (57%) of the samples demonstrating intermediate flora had a BV profile. When applied prospectively, our molecular criteria had total positive and negative predictive values of 96% and 99%, respectively.

CONCLUSIONS

We report a highly reproducible, quantitative tool to objectively analyze vaginal flora that uses cutoff values for the concentrations of A. vaginae and G. vaginalis to establish the molecular diagnosis of BV.

Human lactobacilli as supplementation of clindamycin to patients with bacterial vaginosis reduce the recurrence rate; a 6-month, double-blind, randomized, placebo-controlled study

Background

The primary objective of this study was to investigate if supplementary lactobacilli treatment could improve the initial cure rate after vaginal clindamycin therapy, and secondly, if lactobacilli as repeated adjunct treatment during 3 menstrual cycles could lengthen the time to relapse after initial cure.

Methods

Women (n = 100) with bacterial vaginosis diagnosed by Amsel criteria were after informed consent offered vaginal clindamycin therapy followed by vaginal gelatine capsules containing either 10⁹ freeze-dried lactobacilli or identical placebo capsules for 10 days during 3 menstrual cycles in a double-blind, randomized, placebo-controlled trial.

Results

The initial intent to treat (ITT) analysis for the one-month cure rate was 64% in the lactobacilli group and 78% in the placebo group (p > 0.05). However, any patient with missing or unclassified smears at the initial visit who continued the study and whose next smear indicated a cure was included in the cured group; the study also excluded two of the patients in the lactobacilli group who reported that they did not take any vaginal capsules. With consideration to these population changes, the initial cure rate would be 77% in the lactobacilli group. The 76 cured women were followed for 6 menstrual cycles or until relapse within that time span. At the end of the study, 64.9% (24/37) of the lactobacilli treated women were still BV-free compared to 46.2% (18/39) of the placebo treated women. Comparison of the two groups regarding "Time from cure to relapse" was statistically significant (p = 0.027) in favour of the lactobacilli treatment. Adjuvant therapy with lactobacilli contributed significantly to avoidance of relapse with a proportional Hazard Risk ratio (HR) of 0.73 (0.54–0.98) (p < 0.05)

Conclusion

The study shows that supplementary treatment combining two different strains of probiotic lactobacilli does not improve the efficacy of BV therapy during the first month of treatment, but for women initially cured, adjunct treatment of lactobacilli during 3 menstrual cycles lengthens the time to relapse significantly in that more women remained BV free at the end of the 6-month follow up.

Trial registration number

ISRCTN62879834

Predisposing factors for bacterial vaginosis, treatment efficacy and pregnancy outcome among term deliveries; results from a preterm delivery study

Background

Bacterial vaginosis (BV) during pregnancy is associated with an increased risk of preterm delivery but little is known about factors that could predict BV. We have analyzed if it is possible to identify a category of pregnant women that should be screened for BV, and if BV would alter the pregnancy outcome at term; we have also studied the treatment efficacy of clindamycin.

Methods

Prospective BV screening and treatment study of 9025 women in a geographically defined region in southeast Sweden. BV was defined as a modified Nugent score of 6 and above. Data was collected from the Swedish Medical Birth Register. Women allocated to treatment were supplied with vaginal clindamycin cream. The main outcome goals were to identify factors that could predict BV.

Results

Vaginal smears were consistent with BV criteria in 9.3%. Logistic regression indicates a significant correlation between smoking and BV (p < 0.001) and a greater prevalence of BV in the lower age groups (p < 0.001). We found no correlation between BV and history of preterm deliveries, previous miscarriages, extra-uterine pregnancies, infertility problems or reported history of urinary tract infections–factors that earlier have been associated with BV. Treatment with clindamycin cream showed a cure rate of 77%. Less than 1% of women with a normal vaginal smear in early pregnancy will develop BV during the pregnancy. There was no association between BV and the obstetric outcome among women who delivered at term. Women with BV, both treated patients and nontreated, had the same obstetric outcome at term as women with normal vaginal flora.

Conclusion

BV is more than twice as common among smokers, and there is a higher prevalence in the younger age group. However these two markers for BV do not suffice as a tool for screening, and considering the lack of other risk factors associated with BV, screening of all pregnant women might be a strategy to follow in a program intended to reduce the number of preterm births.

Autoprélèvement vaginal à la recherche d'une vaginose bactérienne pendant la grossesse : étude pilote

OBJECTIVE

To study the feasibility of a screening for bacterial vaginosis by a self-collected vaginal swab during pregnancy. To measure bacterial vaginosis prevalence in a non-representative sample of women.

PATIENTS AND METHODS

A self-collected swab was suggested to 398 women who consulted between 15 and 33 weeks of gestation in three different centres. Gram stain evaluation using Nugent criteria was used for the diagnosis of bacterial vaginosis.

RESULTS

Three hundred and forty-one women agreed to take part in the study (86%). The quality of the swabs was satisfactory in 93% of the cases. Concerning the 15 non-interpretable slides, the cellular and bacterial density was too poor, owing to a poor quality or a low vaginal flora. Thirty-one women (9%) had a bacterial vaginosis--Nugent score included between 7 and 10--and this frequency did not vary according to the centre. Thirty-five women (10%) had an intermediate flora--score between 4 and 6--and this result varied from 2 to 12% depending on the centre, but the difference was not significant.

DISCUSSION AND CONCLUSION

Self-collected swabs to detect bacterial vaginosis are well accepted by most of pregnant women, and the quality of the swabs seems to be satisfactory. In case vaginal flora is intermediate--between 4 and 6--the interpretation of the slides could be difficult.

Late miscarriage and preterm birth after treatment with clindamycin: a randomised consent design study according to Zelen

OBJECTIVE

To screen for bacterial vaginosis (BV) and to investigate the effect of treatment with vaginal clindamycin in order to observe the effect on late miscarriage and delivery prior to 37 completed weeks (primary outcome).

DESIGN

Randomised consent design for clinical trials according to Zelen.

SETTING

Southeast region of Sweden.

POPULATION

A total of 9025 women were screened in early pregnancy.

METHODS

A total of 819 women with a Nugent score of 6 and above were considered to have BV and treated according to Zelen allocation. The incidence of late miscarriage and spontaneous (noniatrogenic) preterm birth was assessed.

MAIN OUTCOME MEASURES

Late miscarriage and spontaneous preterm delivery before 37 weeks.

RESULTS

Therapy with vaginal clindamycin had no significant impact on the incidence of spontaneous preterm delivery prior to 37 completed weeks; OR 0.90, 95% CI 0.40-2.02 (primary outcome variable). However, only 1 of 11 women in the treatment group versus 5 of 12 in the control group delivered prior to 33 completed weeks; OR 0.14, 95% CI 0.02-0.95. Treatment was associated with 32 days longer gestation for the 23 participants who had late miscarriage or spontaneous preterm birth (P= 0.024, Mann-Whitney U test) and significantly fewer infants had a birthweight below 2,500 g (secondary outcome). A follow up of infants born preterm 4 years postnatally indicated that extending gestational age did not increase the number of sequelae.

CONCLUSIONS

Clindamycin vaginal cream therapy was associated with significantly prolonged gestation and reduced cost of neonatal care in women with BV. Early screening for BV and treatment with clindamycin saved approximately 27 euro per woman.

Comparison between Gram stain and culture for the characterization of vaginal microflora: definition of a distinct grade that resembles grade I microflora and revised categorization of grade I microflora

Background

The microbiological diagnosis of bacterial vaginosis is usually made using Nugent's criteria, a useful but rather laborious scoring system based on counting bacterial cell types on Gram stained slides of vaginal smears. Ison and Hay have simplified the score system to three categories and added a fourth category for microflora with a predominance of the Streptococcus cell type. Because in the Nugent system several cell types are not taken into account for a final score, we carried out a detailed assessment of the composition of the vaginal microflora in relation to standard Gram stain in order the improve the diagnostic value of the Gram stain. To this purpose we compared Gram stain based categorization of vaginal smears with i) species specific PCR for the detection of Gardnerella vaginalis and Atopobium vaginae and with ii) tDNA-PCR for the identification of most cultivable species.

Results

A total of 515 samples were obtained from 197 pregnant women, of which 403 (78.3%) were categorized as grade I microflora, 46 (8.9%) as grade II, 22 (4.3%) as grade III and 8 (1.6%) as grade IV, according to the criteria of Ison and Hay. Another 36 samples (7.0%) were assigned to the new category 'grade I-like', because of the presence of diphtheroid bacilli cell types. We found that 52.7% of the grade I-like samples contained Bifidobacterium spp. while L. crispatus was present in only 2.8% of the samples and G. vaginalis and A. vaginae were virtually absent; in addition, the species diversity of this category was similar to that of grade II specimens.

Based on the presence of different Lactobacillus cell types, grade I specimens were further characterized as grade Ia (40.2%), grade Iab (14.9%) and grade Ib (44.9%). We found that this classification was supported by the finding that L. crispatus was cultured from respectively 87.0% and 76.7% of grade Ia and Iab specimens while this species was present in only 13.3% of grade Ib specimens, a category in which L. gasseri and L. iners were predominant.

Conclusion

Further refinement of Gram stain based grading of vaginal smears is possible by distinguishing additional classes within grade I smears (Ia, Iab and Ib) and by adding a separate category, designated grade I-like. A strong correlation was found between grade Ia and the presence of L. crispatus and between grade I-like and the presence of bifidobacteria. This refinement of Gram stain based scoring of vaginal smears may be helpful to improve the interpretation of the clinical data in future studies, such as the understanding of response to treatment and recurrence of bacterial vaginosis in some women, and the relationship between bacterial vaginosis and preterm birth.

Bacterial vaginosis - a laboratory and clinical diagnostics enigma. Review article II

Diagnosing bacterial vaginosis (BV) has long been based on the clinical criteria of Amsel et al., whereby three of four defined criteria must be satisfied. Though there are other criteria and scoring methods which function well in comparison (i.e. Nugent scoring), it is not certain that they will always identify the same category of patients. Point-of-care methods based on various combinations of microbial products, presence of RNA, or more complex laboratory instrumentations such as sensor arrays, have also been introduced for the diagnosis of BV. No method for diagnosing BV can at present be regarded as the best. It could be that--based partly on tacit knowledge on the part of the clinical investigators scoring in the clinic--various scoring systems have been chosen to fit a particular BV-related problem in a particular population. In this review we critically examine these pertinent issues influencing clinical scoring and laboratory diagnostics of BV.