Cervical fluid cytokines in pregnant women: Relation to vaginal wet mount findings and polymorphonuclear leukocyte counts

Large-scale characterisation of the pregnancy vaginal microbiome and sialidase activity in a low-risk Chinese population

Vaginal microbiota-host interactions are linked to preterm birth (PTB), which continues to be the primary cause of global childhood mortality. Due to population size, the majority of PTB occurs in Asia, yet there have been few studies of the pregnancy vaginal microbiota in Asian populations. Here, we characterized the vaginal microbiome of 2689 pregnant Chinese women using metataxonomics and in a subset (n = 819), the relationship between vaginal microbiota composition, sialidase activity and leukocyte presence and pregnancy outcomes. Vaginal microbiota were most frequently dominated by Lactobacillus crispatus or L. iners, with the latter associated with vaginal leukocyte presence. Women with high sialidase activity were enriched for bacterial vaginosis-associated genera including Gardnerella, Atopobium and Prevotella. Vaginal microbiota composition, high sialidase activity and/or leukocyte presence was not associated with PTB risk suggesting underlying differences in the vaginal microbiota and/or host immune responses of Chinese women, possibly accounting for low PTB rates in this population.

Effect of Oral Probiotic Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 on the Vaginal Microbiota, Cytokines and Chemokines in Pregnant Women

Spontaneous preterm birth is associated with vaginal microbial dysbiosis. As certain strains of lactobacilli help restore homeostasis in non-pregnant women, the goal was to determine the effect of Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14 administered orally, twice daily for 12 weeks on the vaginal microbiota, cytokines and chemokines of low-risk pregnant women. A double-blind, placebo-controlled, randomized trial comparing probiotic lactobacilli to placebo daily was performed in 86 asymptomatic pregnant women who had an Intermediate or Bacterial Vaginosis Nugent score at 13 weeks. After drop outs, 32 women receiving probiotics and 34 receiving placebo completed the study. The Nugent score returned to normal in 30% of the women in both groups at 28 weeks and was maintained until 35 weeks. The majority of subjects had normal pregnancy outcomes. Ninety-three bacterial species were detected at 13 weeks, with Lactobacillus iners, Lactobacillus crispatus, Gardnerella vaginalis and Atopobium vaginae being the most abundant across pregnancy. There was no difference in the Shannon diversity index between the probiotic and placebo groups at 13, 28 or 35 weeks. Almost all subjects consumed fermented foods and many of the organisms in the vagina are also known to be present in fermented foods. Interleukin-4 in the placebo group and Interleukin-10 in both probiotic and placebo groups increased slightly at 28 weeks but were not different at 35 weeks when compared to 13 weeks. In conclusion, this study showed no adverse issues resulting from 12 week use of probiotic Lactobacillus strains GR-1 and RC-14 during pregnancy in women at low risk for premature birth. The vaginal microbiota demonstrated flux irrespective of this oral probiotic administration.

Optimising the collection of female genital tract fluid for cytokine analysis in pregnant women

Introduction

To better understand the immunology of pregnancy, study of female genital tract fluid (FGF) is desirable. However the optimum method of collection of FGF in pregnant women for immunological methods, specifically cytokine measurement, is unknown.

Methods

A prospective study of HIV-uninfected pregnant women comparing two methods of FGF collection: polyvinyl acetal sponge collection of cervical fluid (CF) and menstrual cup collection of cervicovaginal fluid (CVF). Samples were collected at 3 time points across the second and third trimesters: 14–21, 22–25 and 26–31 weeks. Multiplex chemi-luminescent assays were used to measure: IFN-γ, IL-1β, IL-2, IL-4, IL-6, IL-8, IL-10, IL-12, IL-13 and TNF-α. Optimal methodology for cytokine normalisation (sample weight, volume and total protein) was explored.

Results

All cytokines were measurable in both fluid types. IL-1β, IL-8 and IL-6 were detected at the highest concentrations (ranking order CF > CVF > plasma). CVF collection was simpler, provided the largest volume of sample (median 0.5 g) with the potential for undiluted usage, and allowed for self-insertion. CF cytokine concentrations were intrinsically associated with sample weight and protein concentration however CVF cytokines were independent of these.

Conclusion

Both methods of collection are robust for measurement of FGF cytokines during pregnancy. We recommend CVF collection using a menstrual cup as a viable option in pregnant women for high dimensional biological techniques.

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PVA sponges and MCs are robust methods for measuring FGF cytokines in pregnancy.

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MCs enable collection of large undiluted CVF volumes for high dimensional assays.

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CVF (not CF) cytokine concentrations are largely independent of sample weight or protein.

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Self-insertion and short collection time of MCs is an attractive option to women.

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Cytokine concentrations are higher in sponge samples reflecting the CF immune site.

Mid-gestational changes in cervicovaginal fluid cytokine levels in asymptomatic pregnant women are predictive markers of inflammation-associated spontaneous preterm birth

OBJECTIVES

Perturbation of the choriodecidual space before the onset of spontaneous preterm birth (sPTB) could lead to a concomitant rise in both cervicovaginal fluid (CVF) cytokine and fetal fibronectin (FFN), and assessing the concentrations of both markers could improve the prediction of sPTB (delivery before 37 completed weeks of gestation). Therefore, we prospectively determined mid-trimester changes in CVF cytokine and FFN concentrations, and their predictive capacity for sPTB in asymptomatic pregnant women.

STUDY DESIGN

CVF collected at 20+0-22+6 weeks (n = 47: Preterm-delivered = 22, Term-delivered = 25) and 26+0-28+6 weeks (n = 50: Preterm-delivered = 17, Term-delivered = 33) from 63 asymptomatic pregnant women at risk of sPTB were examined. Cytokine and FFN concentrations were determined by multiplexed bead-based immunoassay and 10Q Rapid analysis (Hologic, MA, USA) respectively. The 20+0-22+6/26+0-28+6 weeks ratios of cytokines and FFN concentrations were compared between preterm- and term-delivered women using Receiver Operating Characteristics curves to predict sPTB. Also, bacterial 16S rDNA from 64 samples (20+0-22+6 weeks n = 36, 26+0-28+6 weeks n = 28) was amplified by polymerase chain reaction to determine associations between vaginal microflora, cytokine and FFN concentrations.

RESULTS

Changes in RANTES and IL-1β concentrations between 20+0-22+6 and 26+0-28+6 weeks, expressed as a ratios, were predictive of sPTB, RANTES (AUC = 0.82, CI = 0.62-0.94) more so than IL-1β (AUC = 0.71, CI = 0.53-0.85) and FFN (not predictive). Combining these markers (AUC = 0.83, CI = 0.63-0.95) showed similar predictive capacity as RANTES alone. FFN concentrations at 26+0-28+6 weeks correlated with IL-1β (r = 0.4, P = 0.002) and RANTES (r = 0.3, P = 0.03). In addition, there was increased prevalence of vaginal anaerobes including Bacteroides, Fusobacterium and Mobiluncus between gestational time points in women who experienced sPTB compared to the term women (P = 0.0006).

CONCLUSIONS

CVF RANTES and IL-1β in mid-trimester of pregnancy correlate with quantitative FFN. The levels of CVF RANTES and IL-1β decline significantly in women who deliver at term unlike women who deliver preterm. This observation suggests that sPTB may be characterised by sustained choriodecidual inflammation and may have clinical value in serial screening for sPTB if confirmed by larger studies.

Aerobic vaginitis: no longer a stranger

Aerobic vaginitis (AV) is the name given in 2002 to a vaginal infectious entity which was not recognized as such before. It is characterized by abnormal (dysbiotic) vaginal microflora containing aerobic, enteric bacteria, variable levels of vaginal inflammation and deficient epithelial maturation. Although AV and bacterial vaginosis (BV) share some characteristics, such as a diminished number or absence of lactobacilli, increased discharge (fishy smelling in BV, while in severe forms of AV, a foul, rather rotten smell may be present) and increased pH (often more pronounced in AV), there are also striking differences between the two. There is no inflammation in women with BV, whereas the vagina of women with AV often appears red and edematous, and may even display small erosions or ulcerations. The color of the discharge in BV is usually whitish or gray and of a watery consistency, whereas in AV it is yellow to green and rather thick and mucoid. Women with BV do not have dyspareunia, while some women with severe AV do. Finally, the microscopic appearance differs in various aspects, such as the presence of leucocytes and parabasal or immature epithelial cells in AV and the absence of the granular aspect of the microflora, typical of BV. Despite all these differences, the distinction between AV and BV was not recognized in many former studies, leading to incomplete and imprecise diagnostic workouts and erroneous management of patients in both clinical and research settings. The prevalence of AV ranges between 7 and 12%, and is therefore less prevalent than BV. Although still largely undiagnosed, many researchers and clinicians increasingly take it into account as a cause of symptomatic vaginitis. AV can co-occur with other entities, such as BV and candidiasis. It can be associated with dyspareunia, sexually transmitted infections (such as human papilloma virus, human immunodeficiency virus, Trichomonas vaginalis and Chlamydia trachomatis), chorioamnionitis, fetal infection, preterm birth and cervical dysplasia. Many other possible pathological associations are currently under investigation. The diagnosis of AV is made using wet mount microscopy, ideally using phase contrast. An AV score is calculated, according to: lactobacillary grade, presence of inflammation, proportion of toxic leucocytes, characteristics of the microflora and presence of immature epithelial cells. To circumvent the hurdle of microscopic investigation, some groups have begun to develop nucleic-acid-based and enzymatic diagnostic tests, but the detailed information obtained with phase contrast microscopy is irreplaceable. The best treatment is not yet fully determined, but it must be tailored according to the microscopic findings and the patient's needs. There is a role for local estrogen therapy, corticosteroids, antimicrobials and probiotics. Further research will reveal more precise data on diagnosis, pathogenesis, management and prevention.

Vaginal Inflammation: Association between Leukocyte Concentration and Levels of Immune Mediators

PROBLEM

A wide variety of mediators are involved in inflammatory processes. However, the identity of those participating in vaginal immune responses has not been established. We correlated extracellular matrix metalloproteinase inducer (EMMPRIN), matrix metalloproteinase-8 (MMP-8), hyaluronan (HA), hyaluronidase-1 (Hyal-1), human β-defensin-2 (hBD2), and neutrophil gelatinase-associated lipocalin (NGAL) concentrations with the extent of leukocyte infiltration into the vagina and suggest their participation in vaginal inflammation.

METHODS OF STUDY

Vaginal fluid was obtained from 233 women seen at the outpatient clinic in the Department of Obstetrics and Gynecology at Campinas University, Brazil. The magnitude of vaginal inflammation was determined by the leukocyte count on vaginal smears and categorized as no inflammation (0 leukocytes/field), moderate inflammation (1-4 leukocytes/field), and intense inflammation (>4 leukocytes/field). Concentrations of EMMPRIN, MMP-8, HA, Hyal-1, hBD2, and NGAL were determined in vaginal fluid by ELISA.

RESULTS

EMMPRIN, MMP-8, HA, hBD2, and NGAL concentration increased with elevated leukocyte numbers (P < 0.05), while Hyal-1 did not. EMMPRIN concentrations were correlated with HA and MMP-8 levels.

CONCLUSION

EMMPRIN, MMP-8, HA, β-defensin, and NGAL are elevated in women with vaginal inflammation.

Bacterial vaginosis, aerobic vaginitis, vaginal inflammation and major Pap smear abnormalities

The purpose of this investigation was to evaluate the impact of the vaginal milieu on the presence of abnormal Pap smears and a positive human papilloma virus (HPV) test. A cross-sectional study was conducted between June 2014 and May 2015, evaluating the vaginal discharge by fresh wet mount microscopy and comparing these data with Pap smear findings. Wet mount slides were scored for bacterial vaginosis (BV), aerobic vaginitis (AV), presence of Candida and Trichomonas vaginalis. Cytologic evaluation was done on all Pap smears according to the Bethesda criteria. The cobas© HPV Test (Roche) was performed for HPV detection. A total of 622 cases were evaluated. The mean age of the patients was 41.6 ± 10.65 years (range 21-75). Eighty-three women (13.3 %) had a cytology result worse than low-grade squamous intraepithelial lesion (LSIL). When comparing this group with the one with normal or minor [atypical squamous cells of undetermined significance (ASC-US) or LSIL] Pap smear abnormalities, there were no differences in the presence of Candida (32.5 % vs. 33.2 %, p = 1.0), absence of lactobacilli (38.6 % vs. 32.5 %, p = 0.32) or BV (20.5 % vs. 13.2 %, p = 0.09). On the other hand, moderate or severe inflammation (msI) (41.0 % vs. 28.8 %, p = 0,04), moderate or severe AV (msAV) (16.9 % vs. 7.2 %, p = 0.009) and msAV/BV (37.3 % vs. 20.0 %, p = 0.001) were more common in women with such major cervical abnormalities. No significant association was found between deviations of the vaginal milieu and high-risk HPV infection. The presence of msI or msAV, but not BV, is independently associated with an increased risk of major cervical cytological abnormalities, but not with HPV infection.

Do the levels of tumor makers or proinflammatory cytokines in mid-trimester cervical fluid predict early-stage cervical shortening?

AIM

In the present study, we aimed to assess the biomarkers in mid-trimester cervical fluid that can predict early stage cervical shortening.

MATERIAL AND METHODS

We obtained cervical swab specimens from 96 gravidas, after which the cervical length was measured, at approximately 20 weeks of gestation. Cervical length was measured again at 4 weeks after the initial examination. Cervical shortening was noted in 20 women between 20 and 24 weeks of gestation (group A), whereas no cervical shortening was noted in 76 women (group B). We evaluated the use of the levels of tumor markers, proinflammatory cytokines, and matrix metalloproteinase-8 (MMP-8) as candidate biomarkers. CA-125 and carcinoembryonic antigen levels were determined by using an automatic immunoassay system in both groups. Furthermore, IL-1β, IL-8, tumor necrosis factor-α, and MMP-8 levels were measured using an enzyme-linked immunosorbent assay.

RESULTS

The levels of inflammatory cytokines and MMP-8 did not differ between the two groups, and were not correlated with cervical length or the change in cervical length. Although CA-125 and carcinoembryonic antigen levels were higher in group A, they were not statistically significant (P = 0.304 and 0.092, respectively).

CONCLUSION

Early stage cervical shortening in mid-trimester was not associated with an increase in the levels of tumor markers or proinflammatory cytokines in cervical fluid.

Selecting anti-microbial treatment of aerobic vaginitis

Aerobic vaginitis (AV) is a vaginal infectious condition which is often confused with bacterial vaginosis (BV) or with the intermediate microflora as diagnosed by Nugent's method to detect BV on Gram-stained specimens. However, although both conditions reflect a state of lactobacillary disruption in the vagina, leading to an increase in pH, BV and AV differ profoundly. While BV is a noninflammatory condition composed of a multiplex array of different anaerobic bacteria in high quantities, AV is rather sparely populated by one or two enteric commensal flora bacteria, like Streptococcus agalactiae, Staphylocuccus aureus, or Escherichia coli. AV is typically marked by either an increased inflammatory response or by prominent signs of epithelial atrophy or both. The latter condition, if severe, is also called desquamative inflammatory vaginitis. As AV is per exclusionem diagnosed by wet mount microscopy, it is a mistake to treat just vaginal culture results. Vaginal cultures only serve as follow-up data in clinical research projects and are at most used in clinical practice to confirm the diagnosis or exclude Candida infection. AV requires treatment based on microscopy findings and a combined local treatment with any of the following which may yield the best results: antibiotic (infectious component), steroids (inflammatory component), and/or estrogen (atrophy component). In cases with Candida present on microscopy or culture, antifungals must be tried first in order to see if other treatment is still needed. Vaginal rinsing with povidone iodine can provide rapid relief of symptoms but does not provide long-term reduction of bacterial loads. Local antibiotics most suitable are preferably non-absorbed and broad spectrum, especially those covering enteric gram-positive and gram-negative aerobes, like kanamycin. To achieve rapid and short-term improvement of severe symptoms, oral therapy with amoxyclav or moxifloxacin can be used, especially in deep dermal vulvitis and colpitis infections with group B streptococci or (methicillin resistant) Staphylococcus aureus. Since the latter colonizations are frequent, but seldom inflammatory infections, we in general discourage the use of oral antibiotics in women with AV. In cases with a severe atrophy component (more than 10 % of epithelial cells are of the parabasal type), local estrogens can be used; and in postmenopausal or breast cancer patients with a contraindication for estrogens, even a combination of probiotics with an ultra-low dose of local estriol may be considered.

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.

Basic vaginal pH, bacterial vaginosis and aerobic vaginitis: prevalence in early pregnancy and risk of spontaneous preterm delivery, a prospective study in a low socioeconomic and multiethnic South American population

Background

Bacterial vaginosis (BV) increases the risk of spontaneous preterm deliveries (PD) in developed countries. Its prevalence varies with ethnicity, socioeconomic conditions and gestational age. Aerobic vaginitis (AV) has also been implicated with spontaneous PD. The present study aimed to estimate the prevalence of asymptomatic BV, the accuracy of vaginal pH level to predict BV and to estimate the risk of spontaneous PD <34 and <37 weeks’ gestation of BV and AV.

Methods

Women attending prenatal public services in Rio de Janeiro were screened to select asymptomatic pregnant women, < 20 weeks’ gestation, with no indication for elective PD and without risk factors of spontaneous PD. Vaginal smears of women with vaginal pH > = 4.5 were collected to determine the Nugent score; a sample of those smears was also classified according to a modified Donders’ score. Primary outcomes were spontaneous PD < 34 and <37 weeks’ gestation and abortion.

Results

Prevalence of asymptomatic BV was estimated in 28.1% (n = 1699); 42.4% of the smears were collected before 14 weeks’ gestation. After an 8-week follow up, nearly 40% of the initially BV positive women became BV negative. The prevalence of BV among white and black women was 28.1% (95% CI: 24.6%-32.0%) and 32.5% (95% CI: 28.2%-37.2%), respectively. The sensitivity of vaginal pH= > 4.5 and = > 5.0 to predict BV status was 100% and 82%, correspondingly; the 5.0 cutoff value doubled the specificity, from 41% to 84%. The incidence of < 37 weeks’ spontaneous PDs among BV pregnant women with a pH= > 4.5 was 3.8%. The RR of spontaneous PD < 34 and <37 weeks among BV women with pH > =4.5, as compared with those with intermediate state, were 1.24 and 1.86, respectively (Fisher’s exact test, p value = 1; 0.52, respectively, both ns). No spontaneous case of PD or abortion was associated with severe or moderate AV.

Conclusions

A high prevalence of asymptomatic BV was observed without statistically significant difference between black and white women. The RRs of spontaneous PD < 34 and <37 weeks among women with BV, as compared with those with intermediate state were not statistically significant but were consistent with those found in the literature.

Specific inflammatory microenvironments in the zones of the fetal membranes at term delivery

OBJECTIVE

The purpose of this study was to examine the histologic and immunologic differences between fetal membrane zones after membrane rupture at term delivery.

STUDY DESIGN

Fetal membrane explants from postrupture zones (periplacental, middle, rupture) were obtained from women following spontaneous vaginal delivery at term (n = 5). Tissues for histology, protein extracts, and RNA were isolated.

RESULTS

The collagen distribution decreased and the leukocyte density increased from the periplacental zone to the rupture zone. T cells were mainly present in the rupture zone and granulocytes in the middle zone. CXCL10, CXCR1, ICAM-1, -2, PSEL, tumor necrosis factor alpha, and matrix metalloproteinase-9 levels were higher in the middle zone than in the rupture zone and periplacental zone (P < .021). Interleukin-1beta and CXCL8 levels were higher in the rupture zone than in the middle zone and periplacental zone (P = .018 and P < .0001).

CONCLUSION

During labor specific immunologic microenvironments are created in the zones of the fetal membrane that may be involved in their rupture at the end of gestation.

Vaginal Inflammatory Status in Pregnant Women with Normal and Pathogenic Microbiota in Lower Genital Tract

Objective. To assess the vaginal inflammatory status (VIS) in pregnant women, whether symptomatic or asymptomatic, by leukocyte quantification in relation to the microbiota during each pregnancy trimester (T). Materials and Methods. A thousand two hundred and forty eight vaginal exudates from pregnant women were prospectively examined. All the patients underwent a clinical and colposcopic examination and a microbiological study of vaginal exudates. Leukocyte quantification was determined by May-Grunwald Giemsa staining as LNR per field (400X). Results. Statistically significant differences (SSD) in LNR were observed in the VIS of asymptomatic patients (AP) compared with that of symptomatic ones (SP) with normal microbiota: 10–15 for the 1st T, <10, 20 to 25 and >25 for the 2nd T and >25 for the 3rd; with candidiasis: <10 for the 1st T, <10, 15 to 20 and >25 for the 2nd T and <10 and >25 for the 3rd T. In women with trichomoniasis, SSD in the LNR were observed between SP with LNR ≥ 10 and AP with NLR < 10 in the three trimesters altogether. In women with BV, no SSD were observed in the LNR of any AP with respect to SP for the three T. Conclusion. The VIS is influenced by vaginal microbiota and depends on the state of pregnancy and also, on gestational age. The pronounced leukocyte increase in asymptomatic patients in the absence of lower genital tract infection during the third trimester of pregnancy should be highlighted.

Randomized controlled trial of probiotics for the prevention of spontaneous preterm delivery associated with intrauterine infection: study protocol

BACKGROUND

Spontaneous preterm deliveries that occur before the 34th week of gestation, and particularly before the 32nd week of gestation, have been strongly associated to intrauterine infection, ascending from vagina, and represent the largest portion of neonatal deaths and neurological problems. Bacterial vaginosis, characterized by a diminished or absent flora of lactobacilli and increased colonization of several anaerobic or facultative microorganisms, increases two times the risk of preterm delivery before the 34th week. Trials of antibiotics failed to show efficacy and effectiveness against spontaneous preterm birth related to bacterial vaginosis. Some studies indicate benefit from selected probiotics to treat genitourinary infections, including bacterial vaginosis.

OBJECTIVE

The purpose of this study is to evaluate the effectiveness of the early administration of selected probiotics to pregnant women with asymptomatic bacterial vaginosis/intermediate degree infection to reduce the occurrence of spontaneous preterm delivery and related neonatal mortality and morbidity.

METHODS/DESIGN

Women attending public prenatal care services in Rio de Janeiro will be screened to select asymptomatic pregnant women, less than 20 weeks' gestation, with no indication of elective preterm delivery. Those with vaginal pH > = 4.5 and a Nugent score between 4 and 10 (intermediate degree infection or bacterial vaginosis) will be randomized to either the placebo or the intervention group, after written informed consent. Intervention consists in the use of probiotics, Lactobacillus rhamnosus GR-1 and Lactobacillus reuteri RC-14, 2 capsules a day, each capsule containing more than one million bacilli of each strain, for 6-12 weeks, up to the 24th-25th wk of gestation. Ancillary analyses include quantification of selected cervicovaginal cytokines and genotyping of selected polymorphisms. The randomization process is stratified for history of preterm delivery and blocked. Allocation concealment was designed as well as blinding of women, caregivers and outcome evaluators. The study will be supervised by an independent monitoring committee. Outcomes under study are preterm delivery (< 34- < 32 weeks of gestation) and associated neonatal complications: early neonatal sepsis, bronchopulmonary dysplasia, periventricular leukomalacia, necrotizing enterocolitis, and prematurity-related retinopathy; definitions were adapted from those recommended by the 2002 version of the Vermont-Oxford Network. Trial registration at NIH register: NCT00303082.