The prevalence, six-month persistence, and predictive values of laboratory indicators of bacterial vaginosis (nonspecific vaginitis) in asymptomatic women

Research Progress on the Correlation Between Gardnerella Typing and Bacterial Vaginosis

Bacterial vaginosis (BV) is the most common infectious disease of the reproductive tract in women of childbearing age. It often manifests as an imbalance in the vaginal microbiome, including a decrease in Lactobacillus and an increase in anaerobic bacteria. While Gardnerella spp. are considered a major cause of BV, they are also detected in the vaginal microbiome of healthy women. G. vaginalis was the only recognized species of Gardnerella until a recent study characterized three new species, G. leopoldii, G. piotii, and G. swidsinskii. This review describes the different types and genetic diversity of Gardnerella, as well as new findings on the correlation between different Gardnerella spp. and BV.

Asymptomatic Bacterial Vaginosis: To Treat or Not to Treat?

Purpose of Review

The purpose of this review is to summarize current evidence for and against the treatment of asymptomatic bacterial vaginosis (BV) in women.

Recent Findings

Asymptomatic BV is common although its pathogenesis remains incompletely understood. In favor of treating asymptomatic BV is the large body of data supporting that it is sexually transmitted. Along these lines and similar to other STIs, treatment of BV, regardless of symptom status, should be considered to reduce adverse outcomes of infection (i.e. adverse birth outcomes, infertility, post-gynecologic surgery infections, etc.) and prevent further sexual transmission of BV pathogen(s) to sexual partners. One study has found that treatment of women with asymptomatic BV led to a significant reduction in incident chlamydial infections over a 6 month follow-up period, compared to observation-only women. Additionally, some women with asymptomatic BV actually have symptomatic BV but do not recognize these symptoms as an infection. Nevertheless, limitations of the trial regarding treatment of asymptomatic BV as well as the 2020 United States Preventative Task Force recommendation against screening and treatment of asymptomatic BV in pregnant women dampen enthusiasm for recommending treatment in this setting.

Summary

Treatment of asymptomatic BV remains controversial. Additional studies are needed to further investigate the pathogenesis of BV, which will directly influence advances in its diagnosis, treatment, and prevention.

No. 211-Screening and Management of Bacterial Vaginosis in Pregnancy

OBJECTIVE

To review the evidence and provide recommendations on screening for and management of bacterial vaginosis in pregnancy.

OPTIONS

The clinical practice options considered in formulating the guideline.

OUTCOMES

Outcomes evaluated include antibiotic treatment efficacy and cure rates, and the influence of the treatment of bacterial vaginosis on the rates of adverse pregnancy outcomes such as preterm labour and delivery and preterm premature rupture of membranes.

EVIDENCE

Medline, EMBASE, CINAHL, and Cochrane databases were searched for articles, published in English before the end of June 2007 on the topic of bacterial vaginosis in pregnancy.

VALUES

The evidence obtained was rated using the criteria developed by the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Guideline implementation will assist the practitioner in developing an approach to the diagnosis and treatment of bacterial vaginosis in pregnant women. Patients will benefit from appropriate management of this condition.

VALIDATION

These guidelines have been prepared by the Infectious Diseases Committee of the SOGC, and approved by the Executive and Council of the SOGC.

SPONSORS

The Society of Obstetricians and Gynaecologists of Canada.

RECOMMENDATIONS

There is currently no consensus as to whether to screen for or treat bacterial vaginosis in the general pregnant population in order to prevent adverse outcomes, such as preterm birth.

Probiotics in the Prevention and Treatment of Postmenopausal Vaginal Infections: Review Article

Bacterial vaginosis (BV) and complicated vulvovaginal candidiasis (VVC) are frequently occurring vaginal infections in postmenopausal women, caused by an imbalance in vaginal microflora. Postmenopausal women suffer from decreased ovarian hormones estrogen and progesterone. A normal, healthy vaginal microflora mainly comprises Lactobacillus species (spp.), which act beneficially as a bacterial barrier in the vagina, interfering with uropathogens. During premenopausal period, estrogen promotes vaginal colonization by lactobacilli that metabolizing glycogen and producing lactic acid, and maintains intravaginal health by lowering the intravaginal pH level. A lower vaginal pH inhibits uropathogen growth, preventing vaginal infections. Decreased estrogen secretion in postmenopausal women depletes lactobacilli and increases intravaginal pH, resulting in increased vaginal colonization by harmful microorganisms (e.g., Enterobacter, Escherichia coli, Candida, and Gardnerella). Probiotics positively effects on vaginal microflora composition by promoting the proliferation of beneficial microorganisms, alters the intravaginal microbiota composition, prevents vaginal infections in postmenopausal. Probiotics also reduce the symptoms of vaginal infections (e.g., vaginal discharge, odor, etc.), and are thus helpful for the treatment and prevention of BV and VVC. In this review article, we provide information on the intravaginal mechanism of postmenopausal vaginal infections, and describes the effectiveness of probiotics in the treatment and prevention of BV and VVC.

Bacterial vaginosis and the cervicovaginal immune response

Bacterial vaginosis (BV) is a common cause of vaginal discharge in reproductive age women around the world and is associated with several poor reproductive health outcomes, including HIV-1 acquisition. One possible mechanism for this association is the inflammatory immune response induced by BV in the cervical and vaginal mucosae. There is significant heterogeneity in reports of markers of cervicovaginal inflammation in women with BV, likely due to microbial and host diversity, as well as differences in study design. In this article, we review the characteristics of the mucosal immune response in BV, the potential role of lactobacilli in modulating that response, and the impact of individual BV-associated bacterial species on mucosal immunity. We focus on inflammatory markers that are proposed to increase the risk of HIV-1 acquisition.

Six years observation after successful treatment of bacterial vaginosis

OBJECTIVE

The cure rate after treatment of bacterial vaginosis (BV) differs in various investigations, but most studies report a cure rate of 70% after 1 month.

METHODS

A long-term observation study after successful treatment of BV has been undertaken. The original study was a treatment study of BV and included 50 patients.

RESULTS

We were able to identify 44 of the original 50 patients. The mean follow-up time was 6.9 years (range 4.7-9 years). During this time, 21 women (48%) had been free of BV while 23 women had had relapses. There was no difference in the use of broad-spectrum antibiotics, episodes of candida vaginitis, bleeding disturbances, family planning method, development of cervical intraepithelial neoplasia (CIN), or gynecological operations between women with and without relapses. The women with relapses had had a new sexual contact more often during the observation period than women without relapses. There was no difference in hydrogen peroxide production of the lactobacilli among women with or without relapses, and survival analysis shows that most relapses occur during the first year after treatment.

CONCLUSIONS

If patients are successfully treated, half of the patients will stay cured indicating that treatment is of benefit. Most relapses occur during the first year. Our results indicate that the etiology of BV might have something to do with new sexual contacts.

Recent advances in understanding the microbiology of the female reproductive tract and the causes of premature birth

Data derived from molecular microbiological investigations of the human vagina have led to the discovery of resident bacterial communities that exhibit marked differences in terms of species composition. All undergo dynamic changes that are likely due to intrinsic host and behavioral factors. Similar types of bacteria have been found in both amniotic fluid and the vagina, suggesting a potential route of colonization. Given that not all of the species involved in intrauterine infections are readily cultivated, it is important that culture-independent methods of analysis must be used to understand the etiology of these infections. Further research is needed to establish whether an ascending pathway from the vagina to the amniotic cavity enables the development of intrauterine infections.

Screening and management of bacterial vaginosis in pregnancy

OBJECTIVE

To review the evidence and provide recommendations on screening for and management of bacterial vaginosis in pregnancy.

OPTIONS

The clinical practice options considered in formulating the guideline.

OUTCOMES

Outcomes evaluated include antibiotic treatment efficacy and cure rates, and the influence of the treatment of bacterial vaginosis on the rates of adverse pregnancy outcomes such as preterm labour and delivery and preterm premature rupture of membranes.

EVIDENCE

Medline, EMBASE, CINAHL, and Cochrane databases were searched for articles, published in English before the end of June 2007 on the topic of bacterial vaginosis in pregnancy.

VALUES

The evidence obtained was rated using the criteria developed by the Canadian Task Force on Preventive Health Care.

BENEFITS, HARMS, AND COSTS

Guideline implementation will assist the practitioner in developing an approach to the diagnosis and treatment of bacterial vaginosis in pregnant women. Patients will benefit from appropriate management of this condition.

VALIDATION

These guidelines have been prepared by the Infectious Diseases Committee of the SOGC, and approved by the Executive and Council of the SOGC.

SPONSORS

The Society of Obstetricians and Gynaecologists of Canada.

The burden and determinants of reproductive tract infections in India: a population based study of women in Goa, India

BACKGROUND/OBJECTIVE

Reproductive tract infections (RTI) present major health, social, and economic problems in developing countries. Our objective was to describe the prevalence and risk factors of RTIs in a population based sample of women aged 18-45 years.

METHOD

2494 women of 3000 randomly selected from the population defined by a primary health centre catchment area consented to participate. Participants were interviewed regarding complaints and risk factors. Laboratory specimens were collected for the diagnosis of RTIs. Analyses of risk factors were carried out separately for the outcomes of sexually transmitted infections: chlamydia, gonorrhoea, trichomoniasis; and endogenous infections: bacterial vaginosis (BV) and candida.

RESULTS

Endogenous infections were relatively common (BV 17.8%; candida 8.5%), and sexually transmitted infections (STI) were infrequent (4.2%). Factors indicative of poverty and marginalisation were associated with STIs and BV. Gender disadvantage, particularly spousal violence, was associated with BV, while concern about a husband's extramarital relationships, an indicator of sexual risk, was associated with STI. Husband's discharge was strongly associated with STI, and a non-white vaginal discharge was associated with both STI and BV. Condom use and oral contraceptive use were associated with a reduced risk of BV.

CONCLUSIONS

Most of the population burden of RTIs is attributed to endogenous infections. Socioeconomic deprivation and gender disadvantage are associated with raised risk for BV, while the risk factors for STIs indicated that disadvantaged women were likely to be infected by their husbands.

Bacterial vaginosis in pregnancy: diagnosis, screening, and management

Bacterial vaginosis is the most common lower genital tract infection among women of reproductive age. It has been associated with a number of significant obstetric and gynecologic complications, such as preterm labor and delivery, preterm premature rupture of membranes, spontaneous abortion, chorioamnionitis, postpartum endometritis, postcesarean delivery wound infections, postsurgical infections, and subclinical pelvic inflammatory disease. This article focuses on bacterial vaginosis in pregnancy, and discusses approaches to diagnosis, screening, and management.

Bacterial vaginosis - a disturbed bacterial flora and treatment enigma. Review article IV

The syndrome bacterial vaginosis (BV) is characterized by a disturbed vaginal microflora in which the normally occurring lactobacilli yield quantitatively to an overgrowth of mainly anaerobic bacteria. As BV is a possible cause of obstetrics complications and gynaecological disease--as well as a nuisance to the affected women--there is a strong impetus to find a cure. In BV treatment studies, the diagnosis criteria for diagnosis of BV vary considerably and different methods are used for cure evaluation. The design of study protocols varies and there is no consensus respecting a suitable time for follow-up visits. For the purpose of this review, available data were recalculated for 4-week post treatment cure rates. For oral metronidazole the 4-week cure rate was found not to exceed 60-70%. Treatment regimens with topical clindamycin or topical metronidazole have the same cure rates. It can thus be said that no sound scientific basis exists for recommending any particular treatment. There is no evidence of beneficial effects on BV engendered by partner treatment, or by addition of probiotics or buffered gel. Long-term follow-up (longer than 4 weeks) shows a relapse rate of 70%. With a primary cure rate of 60-70%, and a similar relapse rate documented in the reviewed literature, clinicians simply do not have adequate data for determining treatment or designing clinical studies. This is unfortunate since--apart from the obvious patient benefits--clinical studies can often serve as a guide for more basic studies in the quest for underlying disease mechanisms. In the case of BV there is still a need for continued basic studies on the vaginal flora, local immunity to the flora and host-parasite interactions as an aid when designing informative clinical studies.

Rifaximin, a Peculiar Rifamycin Derivative: Established and Potential Clinical Use Outside the Gastrointestinal Tract

Rifaximin is a poorly absorbed semisynthetic rifamycin derivative with a broad spectrum of antibacterial activity including Gram-positive and Gram-negative bacteria, both aerobes and anaerobes. Although originally developed for the treatment of infectious diarrhea, the appreciation of the pathogenic role of gut bacteria in several organic and functional gastrointestinal diseases has increasingly broadened its clinical use. The availability of a topical formulation (a cream containing 5% of the drug) and the lack of transcutaneous absorption pointed out in both animal and human studies has allowed its topical use in skin infections. Furthermore, since the spectrum of antibacterial action of rifaximin includes many organisms (e.g. Bacteroides bivius-disiens, Gardnerella vaginalis, Haemophilus ducreyi) causing genital infections, including Trichomonas vaginalis and Chlamydia trachomatis, its local application in the treatment of bacterial vaginosis (BV) has been attempted. Finally, since periodontal disease, caused by plaque (an aggregate of various bacteria), can be considered a 'local' infection, intrapocket rifaximin was tried in the treatment of periodontal infections. While the efficacy in pyogenic infections of the skin has been confirmed by several investigations, which showed an improvement of both subjective and objective parameters significantly better than that of the reference drug (i.e. chlortetracycline or oxytetracycline), the usefulness of rifaximin in BV and periodontal disease needs to be further studied in well-designed clinical trials.

Evaluation of clinical methods for diagnosing bacterial vaginosis

OBJECTIVE

To determine whether the current clinical criteria for diagnosing bacterial vaginosis can be simplified by using 2 clinical criteria rather than the standard 3 of 4 criteria (Amsel's criteria).

METHODS

This was a prospective observational study of 269 women undergoing a vaginal examination in the Women's Primary Care Center, Division of Research, or Colposcopy Clinic at Women & Infants Hospital. All 4 clinical criteria for diagnosing bacterial vaginosis were collected, and Gram stain was used as the gold standard. Sensitivity and specificity were calculated for each individual criterion, combinations of criteria, and a colorimetric pH and amine card. Receiver operating characteristic curve was generated to estimate the preferred pH and percentage of clue cells for diagnosing bacterial vaginosis.

RESULTS

The prevalence of bacterial vaginosis in our study population was 38.7%. Vaginal pH was the most sensitive of all the criteria, at 89%, and a positive amine odor was the individual criteria with the highest specificity, at 93%. Similar specificity was seen with combinations of 2 criteria and Amsel's criteria. Receiver operating characteristic curve analysis yielded a preferred pH and percentage of clue cells of 5.0 and 20%, respectively. However, a pH of 4.5 or greater improves sensitivity with minimal loss of specificity.

CONCLUSION

The clinical criteria for diagnosing bacterial vaginosis can be simplified to 2 clinical criteria without loss of sensitivity and specificity.

Effectiveness of current therapy of bacterial vaginosis

The study was conducted in order to evaluate effectiveness of the treatment of bacterial vaginosis (BV) with different therapeutic regimes according to recommendations of the World Health Organization (WHO). During a one-year period (February 2000-February 2001) the Sexually Transmitted Diseases (STD) Center was visited by 482 women aged 14-51. The diagnosis of BV was established by standard methods: Amsel's clinical criteria and Gram stain of vaginal discharge. The first-line treatment was oral Metronidazole 2 g single dose. Second line was Metronidazole 500 mg twice daily orally for 7 days or oral Clindamycin 300 mg twice daily for seven days. BV was confirmed in 74 women (15.4%). Most often it was observed in women aged 17-30 years of age. Thirty-three (44.6% of total) were young women 14-21 years of age. Thirty-one (42%) women received a follow-up examination and of those, 11 (38.7%) needed a repeat treatment for BV due to unsatisfactory results of this treatment. It is concluded that treatment of BV with standard methods was not always effective with no significant difference between women under 21 years and older women found in regards to response to treatment. Besides antibiotic treatment, the so-called Probiotics (Lactobacillus acidophilus) can be taken into consideration as an alternative treatment. Additional research about the therapeutic effect of this type of drugs is needed.

Vaginitis: meeting the clinical challenge

Vaginitis is a common gynecologic disorder that is responsible for 10 million office visits to physicians each year. Infectious vaginitis is the most common cause of a vaginal discharge, but other important diagnostic considerations include infectious cervicitis, a physiologic discharge, atrophic vaginitis, and allergic or irritant vaginitis. Although the history and gynecologic examination may suggest the diagnosis, laboratory confirmation should be routinely sought by performance of the vaginal pool wet mount examination, the amine whiff test, determination of the vaginal pH, and the Q-tip test. Once a precise diagnosis is made, effective therapy can then be prescribed. For patients with Candida vaginitis, therapeutic options include either the vaginal administration of a number of available imidazole or triazole antifungal agents or the prescription of the oral triazole agent fluconazole. Oral metronidazole remains the only effective treatment for trichomoniasis in the United States. Bacterial vaginosis, which has been linked to a number of obstetric and gynecologic complications, is effectively treated with oral metronidazole, although vaginal metronidazole gel and oral and vaginal clindamycin formulations are available as well.

Asymptomatic bacterial vaginosis: response to therapy

OBJECTIVE

Bacterial vaginosis causes symptomatic vaginal discharge and has been associated with preterm birth and with the acquisition of human immunodeficiency virus. Half of all women with bacterial vaginosis are free of symptoms, and treatment of these women is controversial. The objective of this study was to determine the extent of poor symptom recognition in this group of women.

STUDY DESIGN

Seventy-five women attending a sexually transmitted disease clinic who had asymptomatic bacterial vaginosis were entered into a randomized, double-blind, placebo-controlled trial comparing metronidazole gel with placebo. Subjects' perceptions about changes in vaginal discharge and odor were determined, and treatment and placebo groups were compared by means of standard statistical analysis.

RESULTS

When subjects were stratified by treatment group, there were no differences in their retrospective assessments of vaginal discharge and odor. A subset of women who had normalization of clinical parameters or of Gram stain scores did admit retrospectively to improvement; however, the difference between this group and the group without normalization was not statistically significant. Twenty-one percent of treated women subsequently had vaginal candidiasis.

CONCLUSIONS

A greater percentage of women with resolution of bacterial vaginosis did retrospectively notice improvement in vaginal discharge and odor in comparison with those women without resolution; however, this was not statistically significant. These findings do not support routine treatment of women with asymptomatic bacterial vaginosis.

Vaginal microflora in healthy women with Gardnerella vaginalis

In order to find the vaginal prevalence of Gardnerella vaginalis in a normal female population, we determined the incidence of G. vaginalis in relation to that of other bacterial genera and species in the vagina. Two-hundred and thirty-nine healthy women were the subjects of this study. Vaginal discharge was collected and bacteriological studies were performed. The mean total aerobe count in the G. vaginalis-positive group was 9.02 log10 colony-forming units (CFU)/g, which was significantly higher (P < 0.0001) than that (6.80 log10 CFU/g) in the G. vaginalis-negative group. In contrast, there was no difference in the mean total anaerobe count between the two groups of subjects (8.82 and 8.24 log10 CFU/g, respectively in the case of including Lactobacillus species count). Also, the mean pH level of vaginal secretion in the G. vaginalis-positive group was 4.58, which was significantly higher (P < 0.005) than that (4.10) in the G. vaginalis-negative group. Aerobes were isolated at equal incidence in the two groups. Anaerobes were isolated at a significantly higher rate in the G. vaginalis-positive group (P < 0.005) than in the G. vaginalis-negative group. The mean count of Lactobacillus species was significantly higher (P < 0.0001) in the G. vaginalis-negative group than in the positive counterpart (7.02 vs 8.66). Elevation of vaginal pH, an increase in the anaerobe count, and decreases in the Lactobacillus species count could be good predictors of the prevalence of bacterial vaginosis in healthy women.

Bacterial vaginosis in pregnancy

Bacterial vaginosis is a clinical condition caused by replacement of the normal hydrogen peroxide producing Lactobacillus sp. in the vagina with high concentrations of characteristic sets of aerobic and anaerobic bacteria. Bacterial vaginosis is the most prevalent cause of vaginal discharge or malodor, although 50 percent of women who meet the criteria for this condition are asymptomatic. Bacterial vaginosis is reported in 10 to 41 percent of women, and new evidence has shown association with maternal and fetal morbidity. Studies have shown that spontaneous abortion, preterm labor, premature birth, preterm premature rupture of the membranes, amniotic fluid infection, postpartum endometritis, and postcesarean wound infections are increased because of infection with bacterial vaginosis during pregnancy. Clinical trials demonstrated important reductions in many of these adverse events with appropriate screening and antimicrobial treatment protocols. New low-cost, diagnostic, point-of-care screening tools are available for rapid screening of patients, affording the physician the opportunity to potentially make a dramatic clinical and cost impact in preventing preterm birth and the costly sequelae of prematurity. Practicing physicians need to be aware of current guidelines for screening and treating pregnant patients for bacterial vaginosis. The authors recommend that all pregnant women be screened and treated with the Centers for Disease Control and Prevention (CDC-P) recommended oral regimens early in pregnancy. Each treated women should be evaluated for "test of cure" 1 month after treatment. Mothers likely to benefit from "screen and treat" approaches include 1) those with the highest concentrations of genital anaerobes and mycoplasmas, 2) women with prior preterm birth or who have low body mass (BMI < 19.8 kg/m2), 3) those with evidence of endometritis before pregnancy, and 4) those who are treated with oral agents effective for both presumed intrauterine mycoplasmas and other bacterial vaginosis flora (i.e., oral clindamycin or erythromycin and metronidazole).

The influence of bacterial vaginosis on in-vitro fertilization and embryo implantation during assisted reproduction treatment

There is growing evidence that the pathogenic effects of bacterial vaginosis may not be confined to the lower genital tract. Possible associations with infertility and effects on fertilization and implantation were studied in patients undergoing in-vitro fertilization (IVF) treatment. High vaginal swabs taken at the time of oocyte collection were assessed by Gram staining. The prevalence of bacterial vaginosis and of intermediate and normal flora in 301 patients was 25.6, 14.0 and 60.4% respectively. Bacterial vaginosis was more prevalent in patients with tubal (31.5%, n = 149) compared with non-tubal (19.7%, n = 152) infertility (odds ratio (OR) 1.87, CI 1.11-3.18, P = 0.02). Bacterial vaginosis did not have an adverse effect on fertilization rate. Further, no significant difference in implantation rates was seen when comparing bacterial vaginosis (15. 8%, OR 1.03, CI 0.66-1.61) and intermediate flora (13.1%, OR 0.82, CI 0.45-1.52) with normal flora (15.5%). Though confidence intervals around the observations were relatively wide, the findings suggest that routine screening for bacterial vaginosis in the hope of improving the success of IVF treatment is not justified. The prevention of complications in pregnancy associated with bacterial vaginosis might be a more relevant indication for screening at the time of IVF treatment, in particular patients with tubal disease, if treatment were shown to be effective for that particular purpose. However, antibiotic treatment before IVF has been shown to be positively disadvantageous for IVF by encouraging other organisms.

Comparison of once-daily and twice-daily dosing of 0.75% metronidazole gel in the treatment of bacterial vaginosis

BACKGROUND AND OBJECTIVES

Bacterial vaginosis is the most common cause of vaginal symptoms in women and has potential complications. Efforts to improve treatment of this disease process are warranted.

GOAL OF THIS STUDY

The goal of this study was to compare the safety and efficacy of once-daily intravaginal administration of 0.75% metronidazole gel for 5 days to the established twice-daily regimen in the treatment of bacterial vaginosis.

STUDY DESIGN

Nonpregnant women with bacterial vaginosis diagnosed by accepted clinical criteria at 14 geographically diverse general gynecology clinics were enrolled in this prospective, randomized, investigator-blind, parallel study. They were treated with either once-daily or twice-daily 0.75% metronidazole gel 5 g intravaginally for 5 days and were reevaluated at 7 to 12 days and 28 to 35 days after completing treatment. Efficacy was determined by clinical criteria. Adverse drug reactions were monitored.

RESULTS

Of the 514 evaluable women enrolled, bacterial vaginosis was cured at the first return visit among evaluable patients in 153 of 199 (77%) of those who received the once-daily and in 157 of 196 (80%) of those who received the twice-daily administration. Bacterial vaginosis was cured among evaluable patients at the final visit in 104 of 180 (58%) of those who received once-daily and 109 of 178 (61%) of those who received the twice-daily regimen. Intent-to-treat analysis showed cure at 1 month in 118 of 207 (57%) of those treated once daily and 129 of 209 (62%) of those treated twice daily. Side effects were mild, and none caused treatment discontinuation.

CONCLUSIONS

Once-daily dosing of 0.75% metronidazole gel 5 g for 5 days yields efficacy, safety, and tolerance equivalent to the currently used twice-daily dosing in the treatment of bacterial vaginosis, adding another competitive choice to the available therapeutic options for this condition.

Evaluation and management of vaginitis

OBJECTIVE

To evaluate recent advances in our understanding of the clinical relevance, diagnosis, and treatment of vaginal infections, and to determine an efficient and effective method of evaluating this clinical problem in the outpatient setting.

DATA SOURCES

Relevant papers on vaginitis limited to the English language obtained through a MEDLINE search for the years 1985 to 1997 were reviewed.

DATA SYNTHESIS

Techniques that enable the identification of the various strains of candida have helped lead to a better understanding of the mechanisms of recurrent candida infection. From this information a rationale for the treatment of recurrent disease can be developed. Bacterial vaginosis has been associated with complications, including upper genital tract infection, preterm delivery, and wound infection. Women undergoing pelvic surgery, procedures in pregnancy, or pregnant women at risk of preterm delivery should be evaluated for bacterial vaginosis to decrease the rate of complications associated with this condition. New, more standardized criteria for the diagnosis of bacterial vaginosis may improve diagnostic consistency among clinicians and comparability of study results. Use of topical therapies in the treatment of bacterial vaginosis are effective and associated with fewer side effects than systemic medication. Trichomonas vaginalis, although decreasing in incidence, has been associated with upper genital tract infection. Therapy of T. vaginalis infection has been complicated by an increasing incidence of resistance to metronidazole.

CONCLUSIONS

Vaginitis is a common medical problem in women that is associated with significant morbidity and previously unrecognized complications. Research in recent years has improved diagnostic tools as well as treatment modalities for all forms of vaginitis.

Treatment of vaginitis

OBJECTIVE

The purpose of this study was to evaluate the efficacy of metronidazole 500 mg and miconazole nitrate 100 mg (Neo-Penotran, Embil Pharmacy Company, Istanbul, Turkey) in the treatment of vaginitis.

METHOD

One hundred patients (mean age 26.5 years, range 18-50) with a clinical diagnosis of vaginitis entered this open, noncomparative study. Each patient inserted a Neo-Penotran pessary twice daily for 14 days. Assessments were carried out at the beginning of the study and 15 and 22 days after the start of therapy. Student's t-test was used for the statistical analysis.

RESULTS

Out of 100 patients who were initially recruited to the study, 20 were subsequently excluded, leaving a total of 80 patients (80%) who completed the full course of treatment. Vaginitis was resolved in 75% of cases, it improved in 18% and was unchanged in 7%. The success rate for the treatment of trichomoniasis was 80%, 93.4% for bacterial vaginosis and 84.4% for candidal vaginitis.

CONCLUSION

Neo-Penotran pessaries represent a novel and effective formulation for the treatment of common types of vaginitis and this pessary may also be of particular value in the treatment of resistant or recurrent vaginitis.

[The isolation of Streptococcus morbillorum from vaginal exudates]

We have tested 195 vaginal secretions sent by Gynecology Service of this hospital between the years 1988-1990. We achieved positive culture for streptococci in 58 (30%) of these cultures, 26 (44.8%) corresponding to Streptococcus morbillorum 9 (15.5%), to Gardnerella vaginalis 5 (8.6%), to Enterococcus faecalis-durans and to Streptococcus agalactiae, 3 (5.1%) to Streptococcus mitis and milleri 2 (3.4%), to Streptococcus bovis and cremoris, and 1 (1.7%) to Streptococcus salivarius, equinus and sanguis II respectively. We previously found that 52.8% of these patients were positive for vaginal candidiasis. The bacteriological identification done by the API 20 STREP System (bioMerieux GmbH, Nútingen, Germany) provides a typical pattern ("good identification") for the Streptococcus morbillorum.

Bacterial vaginosis: efficacy and safety of intravaginal metronidazole treatment

OBJECTIVE

We evaluated the effectiveness and safety of intravaginal metronidazole in the treatment of bacterial vaginosis. Demographic data, Gram stain score, and individual clinical diagnostic criteria for bacterial vaginosis were evaluated for association with therapeutic outcome.

METHODS

According to accepted diagnostic criteria and blinded Gram stain scoring for quality control, a multicenter, prospective, double-blinded trial of patients randomized to either 0.75% metronidazole gel 5 gm twice daily for 5 days or placebo was undertaken. Therapeutic response after completion of treatment was evaluated by examination at 4 to 16 days and again at 28 to 32 days for patients initially cured.

RESULTS

After metronidazole treatment, 38 (78%) of 49 patients were cured initially, compared with 11 (27%) of 41 placebo recipients (p < 0.001). One month after treatment 31 (91%) of 34 in the group initially cured by metronidazole remained cured. Side effects were uncommon and mild. Significant intercenter differences were noted for vaginal discharge assessment but not for other diagnostic criteria. Among patients cured initially with metronidazole, mean Gram stain score was 0.58 among those in whom cure was maintained versus 2.33 for those in whom recurrent bacterial vaginosis developed 1 month after treatment (p = 0.03). Curative metronidazole treatment was found initially in 4 (100%) of 4 patients with sperm present on gram stain compared with 34 (76%) of 45 with sperm absent (p = 0.56) and in 6 (100%) of 6 and 25 (89%) of 28, respectively, at the final visit (p = 1.0).

CONCLUSIONS

Intravaginal metronidazole is effective, safe, well-tolerated, durable therapy for bacterial vaginosis. Characterization of vaginal discharge appears to be the most variable among the diagnostic criteria for bacterial vaginosis. Gram stain score may be able to identify patients cured early after therapy who are at risk for later recurrence. Exposure to semen does not appear to affect efficacy of intravaginal metronidazole.

Effect of lactic acid suppositories compared with oral metronidazole and placebo in bacterial vaginosis: a randomised clinical trial

OBJECTIVE

To compare the effect of lactic acid locally, metronidazole orally and placebo in women with bacterial vaginosis.

DESIGN

Randomised clinical trial.

SETTING

30 general practices in the Netherlands.

PATIENTS

125 women consulting the general practitioner for symptomatic bacterial vaginosis.

MAIN OUTCOME MEASURES

Duration of subjective symptoms, recurrence of symptoms, clinically diagnosed cure, adverse events.

RESULTS

Survival analysis showed a significantly faster disappearance of symptoms in the metronidazole category compared with both lactic acid and placebo (p = 0.0005 metronidazole v placebo, p = 0.0002 metronidazole v lactic acid p = 0.6521 lactic acid v placebo [The stratified Mantel Cox test]). The median duration until absence of symptoms was 21 days for metronidazole and 80 days for placebo. Disappearance of symptoms did not occur in 50% of the lactic acid group in 90 days. Recurrence rates of symptoms were similar over the treatment categories (p = 0.13 metronidazole v placebo and p = 0.12 lactic acid v placebo). After 2 weeks cure rates (cure defined as less than three of four clinical criteria present) were 83%, 49% and 47% for metronidazole, lactic acid and placebo category respectively. At that time cure rates (cure defined as none of three clinical criteria present) were 10%, 0% and 3%. After four weeks and three months these figures were: 55%, 20%, 20% and 64%, 28%, 28%. No differences in adverse events were found between the three interventions.

CONCLUSIONS

Lactic acid suppositories are ineffective, metronidazole capsules are effective on signs and symptoms in bacterial vaginosis. A considerable proportion of the patients recover without active medication.

Epidemiology of bacterial vaginosis

Studies of the prevalence of and risk factors for bacterial vaginosis are flawed by imprecision in diagnosis, failure to study large and well-characterized populations, selection bias, and failure to correct for confounding variables. Prevalences range from 5% for women without any symptoms to 25% for those with gynecologic symptoms. Although bacterial vaginosis is associated with nonwhite race and intrauterine contraceptive device use, these may represent surrogate markers for other presently unappreciated risk factors.

Physical characterization of the pore forming cytolysine from Gardnerella vaginalis

The cytolytic toxin (CTox) produced by Gardnerella vaginalis is able to form voltage-dependent cationic channels when incorporated in lipid membranes (Moran et al. (1991) FEBS Lett. 283, 317-320). Osmotic protection experiments show that toxin incorporated in human erythrocytes forms pores between 18 A and 28 A in diameter. A hypothesis of pore formation as a primary event to produce cytolysis is proposed. The CTox activity increases when cells are depolarized by increasing the extracellular K+ concentration, probably reflecting the voltage dependent character of CTox formed channels. The cytolytic effect of the toxin was prevented by low temperatures and was a function of the extracellular Ca2+ concentration, suggesting a Ca2+ influx as part of the lytic mechanism. Binding of CTox to erythrocytes was dependent on external Ca2+ and was less temperature-dependent. Dose-response analysis suggests cooperativity of the toxin for the lytic activity, although no direct evidence of oligomerization has been found.

Gardnerella vaginalis: characteristics, clinical considerations, and controversies

The clinical significance, Gram stain reaction, and genus affiliation of Gardnerella vaginalis have been controversial since Gardner and Dukes described the organism as the cause of "nonspecific vaginitis," a common disease of women which is now called bacterial vaginosis. The organism was named G. vaginalis when taxonomic studies showed that it was unrelated to bacteria in various genera including Haemophilus and Corynebacterium. Electron microscopy and chemical analyses have elucidated the organism's gram-variable reaction. Controversy over the etiology of bacterial vaginosis was largely resolved by (i) studies using improved media and methods for the isolation and identification of bacteria in vaginal fluids and (ii) standardization of criteria for clinical and laboratory diagnosis. Besides G. vaginalis, Mobiluncus spp., Mycoplasma hominis, and certain obligate anaerobes are now acknowledged as participants in bacterial vaginosis. The finding that G. vaginalis, Mobiluncus spp., and M. hominis inhabit the rectum indicates a potential source of autoinfection in addition to sexual transmission. Extravaginal infections with G. vaginalis are increasingly recognized, especially when the toxic anticoagulant polyanetholesulfonate is omitted from blood cultures and when urine cultures are incubated anaerobically for 48 h. The finding that mares harbor G. vaginalis suggests that an equine model can be developed for studies of Gardnerella pathogenesis.

Characteristics of three vaginal flora patterns assessed by gram stain among pregnant women. Vaginal Infections and Prematurity Study Group

This study was undertaken to define the characteristics and persistence of vaginal flora in 7918 pregnant women at 23 to 26 weeks' gestation. Vaginal smears were categorized as normal (predominant lactobacilli), intermediate (reduced lactobacilli), or positive for bacterial vaginosis. The women with normal flora were least likely to have elevated vaginal pH, amine odor, milky discharge, or colonization by Gardnerella, Bacteroides, or genital mycoplasmas. Women with intermediate vaginal flora had intermediate frequencies of these clinical signs and microorganisms. Group B streptococci and yeast were associated with normal or intermediate flora, whereas Neisseria gonorrhoeae and Chlamydia trachomatis were recovered more frequently from women with intermediate flora or bacterial vaginosis. Trichomonas vaginalis was most associated with intermediate flora. At follow-up, 81% of the women with normal flora had remained normal. Of the women with intermediate flora, 32% acquired bacterial vaginosis and 30% shifted to normal flora. Only 12% of the women with bacterial vaginosis had shifted to normal flora. We conclude that there are two primary stable vaginal flora patterns (normal flora or bacterial vaginosis) and a third less distinct transitional flora pattern between these two.

Bacterial vaginosis: current review with indications for asymptomatic therapy

Bacterial vaginosis is a definable clinical entity whose exact origin is unknown. A shift in normal vaginal flora from aerobic, predominantly but not exclusively lactobacilli, to a predominantly anaerobic flora characterizes the condition. More than one half of all women with bacterial vaginosis have no symptoms. The condition is not entirely benign. The potentially pathogenic bacteria present in the vagina in large numbers place these women at risk for postoperative morbidity and adverse obstetric outcome. Sexual transmission has not been proved, but therapeutic cures sometimes require that patient and partner be treated simultaneously. Recommended therapy is with metronidazole or clindamycin and must be given for 7 days for maximal effectiveness. Recurrence of disease can be a problem.

Bacterial vaginosis

Bacterial vaginosis (BV) is the most common of the vaginitides affecting women of reproductive age. It appears to be due to an alteration in the vaginal ecology by which Lactobacillus spp., the predominant organisms in the healthy vagina, are replaced by a mixed flora including Prevotella bivia, Prevotella disiens, Porphyromonas spp., Mobiluncus spp., and Peptostreptococcus spp. All of these organisms except Mobiluncus spp. are also members of the endogenous vaginal flora. While evidence from treatment trials does not support the notion that BV is sexually transmitted, recent studies have shown an increased risk associated with multiple sexual partners. It has also been suggested that the pathogenesis of BV may be similar to that of urinary tract infections, with the rectum serving as a reservoir for some BV-associated flora. The organisms associated with BV have also been recognized as agents of female upper genital tract infection, including pelvic inflammatory disease, and the syndrome BV has been associated with adverse outcome of pregnancy, including premature rupture of membranes, chorioamnionitis, and fetal loss; postpartum endometritis; cuff cellulitis; and urinary tract infections. The mechanisms by which the BV-associated flora causes the signs of BV are not well understood, but a role for H2O2-producing Lactobacillus spp. in protecting against colonization by catalase-negative anaerobic bacteria has been recognized. These and other aspects of BV are reviewed.

Metronidazole pessaries compared with placebo in the treatment of bacterial vaginosis

In a randomized, double-blind clinical trial from general practice, 500 mg metronidazole pessaries applied once daily for seven days were compared with placebo in the treatment of bacterial vaginosis. Seventy-five women completed the study. At the follow-up visit immediately after completion of treatment, none of the patients on metronidazole fulfilled the criteria for bacterial vaginosis, compared with 12 (35%) in the placebo group (p less than 0.001). Nine (22%) of the patients treated with metronidazole harboured Gardnerella vaginalis after treatments, compared with 31 (91%) in the placebo group (p less than 0.001). Symptoms had improved or disappeared in 33 (80%) on metronidazole, and in 18 (53%) on placebo therapy (p less than 0.05). Four weeks after the follow-up visit, symptoms were reported by 28% in the metronidazole group and by 44% in the placebo group (p greater than 0.05). Metronidazole pessaries are effective in the treatment of bacterial vaginosis.

Vaginal infections in adult women

Often trivialized by the medical profession, vaginitis in adult women is not only extremely common but is the source of considerable distress and often results in marked suffering. Epidemiologic studies described in this article indicate the high prevalence of vaginitis and the large number of causes. Although the majority of infections in women are due to bacterial vaginosis, VVC, and trichomoniasis, it is clear that many other causes exist, and we have yet to discover the etiology of many clinical syndromes. Considerable progress has been made in understanding the pathogenesis of the three common vaginitides. Although excellent progress has been made by the pharmaceutical industry in providing new drugs for vaginitis, any further progress will require a better understanding of etiology and pathogenesis. Vaginitis causes major symptoms and is more than a nuisance problem. Clinicians owe it to their patients to attempt to make an accurate diagnosis and not to rely on empiric therapy.

Identification and partial characterization of a cytolytic toxin produced by Gardnerella vaginalis

Generation and release into the culture medium of a cytolytic toxin by Gardnerella vaginalis has been demonstrated. Addition of starch and of the nonionic detergent Tween 80 to the culture medium was essential to recover cytolytic activity. A protein with an apparent molecular mass of 61 to 63 kDa was purified from the culture supernatants showing lytic activity towards erythrocytes and nucleated cells, such as human endothelial cells and human neutrophils. The protein had marked selectivity for human erythrocytes, while erythrocytes from other species were not lysed or were lysed at much higher concentrations of the protein than those needed for human erythrocytes. The cytolytic activity was remarkably unstable in polar media, but was stabilized by nonionic detergents, by binding, or by insertion into the target cell membrane, suggesting its amphiphilic nature.

Bacterial vaginosis: diagnostic and pathogenetic findings during topical clindamycin therapy

We examined subjective and objective correlates among 67 women with symptomatic bacterial vaginosis before and after treatment with intravaginal clindamycin or placebo. We found no preponderance of any sexual practices among these patients. Nine patients (13.4%) had had hysterectomy. Whereas odor and discharge were the most common symptoms, 30 patients (44.8%) also complained of vulvovaginal irritation. Symptoms correlated poorly with objective therapeutic outcome. On examination the diagnosis would have been missed in seven patients (10.4%) if the clinician relied on presence of an abnormal vaginal discharge to suggest bacterial vaginosis. Vaginal pH greater than 4.5 was found immediately after curative therapy in 59.6% of patients. Mobiluncus spp. morphotypes were 99.0% specific and 52.1% sensitive and proline aminopeptidase activity in vaginal fluid was 84.4% sensitive and 70.2% specific for diagnosis. Our Gram stain criteria yielded no false-negative results, 6.1% false-positive, and frequent indeterminate results after therapy. We found little evidence for sexual transmission of bacterial vaginosis. Recurrence after effective therapy was not predicted by vaginal pH elevation, positive or indeterminate Gram stain result, or positive proline aminopeptidase test.

Prevalence of bacterial vaginosis and its association with genital infections, inflammation, and contraceptive methods in women attending sexually transmitted disease and primary health clinics

In an epidemiological survey of 2128 women attending a sexually transmitted diseases clinic for the first time and 200 attending two primary health clinics, 26% and 27% respectively were found to have bacterial vaginosis. The prevalence increased significantly with age, being diagnosed in 22.8% (326/1431) of women aged 14-24 years, and in 33.3% (232/697) of those aged greater than or equal to 25 years. Bacterial vaginosis was associated with gonorrhoea and with chlamydial infection, but was negatively associated with genital papillomavirus infection and yeast infection. Women using barrier contraceptives had a significantly lower prevalence of bacterial vaginosis than those using an intrauterine device or no contraceptive. Women less than or equal to 24 years old using oral contraceptives had a significantly lower prevalence of bacterial vaginosis than those not using contraceptives. Patients without gonorrhoea or chlamydial infection but with vaginal or urethral inflammatory signs had a significantly higher prevalence of bacterial vaginosis than those without inflammatory signs. These findings may have implications regarding complications associated with lower genital tract infections and may strengthen the hypothesis that bacterial vaginosis is a risk factor for pelvic inflammatory disease.

Statistical evaluation of diagnostic criteria for bacterial vaginosis

Bacterial vaginosis is the most common cause of vaginitis in women of reproductive age. In an attempt to clarify diagnosis of this condition, various parameters of signs and symptoms and groups of parameters were compared with classical diagnostic criteria in 310 patients. There was no significant difference in positive diagnosis rates between the Amsel et al. criteria and those of Thomason et al. (p = 0.25). The single most reliable indicator of bacterial vaginosis was the presence of clue cells on wet mount examination of vaginal secretions (sensitivity 98.2%, specificity 94.3%, positive predictive value 89.9%, negative predictive value 99.0%). The best two combinations of parameters for rapid accurate clinical diagnosis were clue cells and odor on alkalinization (sensitivity 99.5%) positive predictive value 98.8%, negative predictive value 92.1%). Gram stain criteria (bacterial morphologic types) were less accurate predictors of the disease (sensitivity 97.0%, specificity 66.2%, positive value 57.2%, negative predictive value 97.9%). Even when the bacterial morphologic type criteria were combined with presence of clue cells, predictive accuracy did not exceed that of clue cells on wet mount examination alone (sensitivity 93.9%, specificity 84.7%, positive predictive value 74.2%, negative predictive value 96.8%). Homogeneous discharge was found to be of little diagnostic value.

Comparison of methods for diagnosing bacterial vaginosis among pregnant women

The diagnosis of bacterial vaginosis is usually based on clinical criteria including homogeneous vaginal discharge, an elevated vaginal pH, the presence of clue cells, and an amine odor. We have evaluated the vaginal flora and clinical signs for 593 pregnant women. Gardnerella vaginalis, Bacteroides spp., and Mycoplasma hominis were isolated more frequently among women with clinical signs than among those without clinical signs of bacterial vaginosis in multivariable analyses that controlled for other bacteria. To determine the laboratory method that best predicted bacterial vaginosis, we calculated the sensitivity, specificity, and predictive value of positive and negative tests for Gram-stained vaginal smears, gas-liquid chromatography of vaginal fluid, and G. vaginalis cultures compared with clinical signs. G. vaginalis culture was sensitive (92%) and both gas-liquid chromatography (78%) and Gram-stained vaginal smears (62%) were moderately sensitive in identifying women with three of the four clinical signs of bacterial vaginosis. However, the Gram-stained vaginal smear (95%) was more specific than G. vaginalis culture (69%) or gas-liquid chromatography (81%). The predictive value of a positive test was also higher for the Gram staining (76%) than for G. vaginalis culture (41%) or gas-liquid chromatography (48%).