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Chen L, Li J, Xiao B. The role of sialidases in the pathogenesis of bacterial vaginosis and their use as a promising pharmacological target in bacterial vaginosis. Front Cell Infect Microbiol 2024; 14:1367233. [PMID: 38495652 PMCID: PMC10940449 DOI: 10.3389/fcimb.2024.1367233] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/08/2024] [Accepted: 02/19/2024] [Indexed: 03/19/2024] Open
Abstract
Bacterial vaginosis (BV) is an infection of the genital tract characterized by disturbance of the normally Lactobacilli-dominated vaginal flora due to the overgrowth of Gardnerella and other anaerobic bacteria. Gardnerella vaginalis, an anaerobic pathogen and the major pathogen of BV, produces sialidases that cleave terminal sialic acid residues off of human glycans. By desialylation, sialidases not only alter the function of sialic acid-containing glycoconjugates but also play a vital role in the attachment, colonization and spread of many other vaginal pathogens. With known pathogenic effects, excellent performance of sialidase-based diagnostic tests, and promising therapeutic potentials of sialidase inhibitors, sialidases could be used as a biomarker of BV. This review explores the sources of sialidases and their role in vaginal dysbiosis, in aims to better understand their participation in the pathogenesis of BV and their value in the diagnosis and treatment of BV.
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Affiliation(s)
- Liuyan Chen
- Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China
| | - Jiayue Li
- School of Medicine, University College Dublin, Dublin, Ireland
| | - Bingbing Xiao
- Department of Obstetrics and Gynecology, Peking University First Hospital, Beijing, China
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Chudzicka-Strugała I, Gołębiewska I, Banaszewska B, Trzciński M, Brudecki G, Elamin W, Zwoździak B. Bacterial Vaginosis (BV) and Vaginal Microbiome Disorders in Women Suffering from Polycystic Ovary Syndrome (PCOS). Diagnostics (Basel) 2024; 14:404. [PMID: 38396443 PMCID: PMC10888114 DOI: 10.3390/diagnostics14040404] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Revised: 01/23/2024] [Accepted: 01/25/2024] [Indexed: 02/25/2024] Open
Abstract
Introduction: Polycystic ovary syndrome (PCOS) is a multifactorial, heterogeneous endocrine and metabolic disorder in women. Due to its association with the menstrual cycle and fertility disorders, the importance of this problem is emphasized especially in patients of reproductive age. Based on a number of analyses, the effect of PCOS on altering the diversity of the microbiome (e.g., intestinal or vaginal) is suggested. Vaginal dysbiosis can result in BV (bacterial vaginosis). The purpose of this study was to assess the prevalence of BV in patients with PCOS, as well as to determine the most reliable diagnostic factors. Material and Methods: Retrospective analysis of microbiological findings (2018-2022) of PCOS patients (n = 594) of reproductive age. The present analysis focused on the results of patients with PCOS (n = 380) and vaginal discharge with pH ≥ 4.4 and suspected BV. Biological material was a vaginal swab/vaginal secretion. The most commonly used routine methods for assessing BV were the Amsel analysis and the Nugent scoring system. Results: Patients with PCOS and vaginal fluid pH ≥ 4.4 and suspected BV (n = 380) accounted for 64% of all PCOS patients (n = 594). The relationship between pH and detection of "clue cells" showed significant dependency and increased with leukocytes. The pH measurement also showed dependency on high G. vaginalis counts. In addition, the elimination of lactic acid bacteria (LAB) in vaginal secretions was associated with an increase in the number of leukocytes with increasing pH values. A marked increase in G. vaginalis was found in more than half (56.8%) of PCOS women (n = 380) with suspected BV. No dependency was observed between the absence of LAB and the diagnosis of BV on a positive G. vaginalis culture. Of the n = 380 patients with PCOS, 191 (50%) had a Nugent score ≥ 7 positive for BV. No dependency was observed between the number of patients with Candida sp. in vaginal secretions and pH, BV (with clue cells), or elevated leukocyte levels. The LRM was adjusted and the statistical model represented by the following formula was obtained: log(p/(1 - p)) = -1.18 + 1.24 × Group4.6 + 1.08 × Group4.8 + 1.66 × Group5.4. Conclusions: Based on the present analysis, BV appears to be more common in patients with PCOS than in the non-PCOS population. Chronic inflammation in PCOS patients and abnormalities in the vaginal microbiome may predispose to the development of BV. In women with PCOS, BV may be one of the unrecognized causes of infertility or complications of pregnancy. Despite the potential link between PCOS and the development of BV, the extent to which this syndrome contributes to vaginal dysbiosis and reproductive complications requires further study.
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Affiliation(s)
- Izabela Chudzicka-Strugała
- Department of Medical Microbiology, Poznan University of Medical Sciences, Rokietnicka 10, 60-806 Poznan, Poland; (I.C.-S.); (B.Z.)
| | | | - Beata Banaszewska
- Department of Laboratory Diagnostics, Poznan University of Medical Sciences, Szamarzewskiego 82/84, 60-569 Poznan, Poland;
| | - Mateusz Trzciński
- Department of Infertility Diagnostics and Treatment, Poznan University of Medical Sciences, 61-701 Poznan, Poland;
| | - Grzegorz Brudecki
- Group 42 (Healthcare), Masdar City, Abu Dhabi P.O. Box 112778, United Arab Emirates; (G.B.); (W.E.)
| | - Wael Elamin
- Group 42 (Healthcare), Masdar City, Abu Dhabi P.O. Box 112778, United Arab Emirates; (G.B.); (W.E.)
| | - Barbara Zwoździak
- Department of Medical Microbiology, Poznan University of Medical Sciences, Rokietnicka 10, 60-806 Poznan, Poland; (I.C.-S.); (B.Z.)
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Lingasamy P, Modhukur V, Mändar R, Salumets A. Exploring Immunome and Microbiome Interplay in Reproductive Health: Current Knowledge, Challenges, and Novel Diagnostic Tools. Semin Reprod Med 2023; 41:172-189. [PMID: 38262441 PMCID: PMC10846929 DOI: 10.1055/s-0043-1778017] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/25/2024]
Abstract
The dynamic interplay between the immunome and microbiome in reproductive health is a complex and rapidly advancing research field, holding tremendously vast possibilities for the development of reproductive medicine. This immunome-microbiome relationship influences the innate and adaptive immune responses, thereby affecting the onset and progression of reproductive disorders. However, the mechanisms governing these interactions remain elusive and require innovative approaches to gather more understanding. This comprehensive review examines the current knowledge on reproductive microbiomes across various parts of female reproductive tract, with special consideration of bidirectional interactions between microbiomes and the immune system. Additionally, it explores innate and adaptive immunity, focusing on immunoglobulin (Ig) A and IgM antibodies, their regulation, self-antigen tolerance mechanisms, and their roles in immune homeostasis. This review also highlights ongoing technological innovations in microbiota research, emphasizing the need for standardized detection and analysis methods. For instance, we evaluate the clinical utility of innovative technologies such as Phage ImmunoPrecipitation Sequencing (PhIP-Seq) and Microbial Flow Cytometry coupled to Next-Generation Sequencing (mFLOW-Seq). Despite ongoing advancements, we emphasize the need for further exploration in this field, as a deeper understanding of immunome-microbiome interactions holds promise for innovative diagnostic and therapeutic strategies for reproductive health, like infertility treatment and management of pregnancy.
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Affiliation(s)
| | - Vijayachitra Modhukur
- Competence Centre on Health Technologies, Tartu, Estonia
- Department of Obstetrics and Gynecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
| | - Reet Mändar
- Competence Centre on Health Technologies, Tartu, Estonia
- Department of Microbiology, Institute of Biomedicine and Translational Medicine, University of Tartu, Tartu, Estonia
| | - Andres Salumets
- Competence Centre on Health Technologies, Tartu, Estonia
- Department of Obstetrics and Gynecology, Institute of Clinical Medicine, University of Tartu, Tartu, Estonia
- Division of Obstetrics and Gynecology, Department of Clinical Science, Intervention and Technology, Karolinska Institute and Karolinska University Hospital, Stockholm, Sweden
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Martins BCT, Guimarães RA, Alves RRF, Saddi VA. Bacterial vaginosis and cervical human papillomavirus infection in young and adult women: a systematic review and meta-analysis. Rev Saude Publica 2022; 56:113. [PMID: 36629704 PMCID: PMC9749738 DOI: 10.11606/s1518-8787.2022056004412] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2021] [Accepted: 03/25/2022] [Indexed: 12/28/2022] Open
Abstract
OBJECTIVE To investigate the association between bacterial vaginosis and cervical human papillomavirus (HPV) infection in young and adult women. METHODS This systematic review and meta-analysis was based on the Prisma methodological guidelines. PubMed and Web of Science were searched using the following descriptors: "bacterial vaginosis and HPV", in June 2019. Articles published from 2012 to 2019 were included. Inclusion criteria were original studies that investigated the association between bacterial vaginosis and cervical HPV infection; articles published in English, Spanish or Portuguese; studies conducted in young and adult, non-pregnant, non-HIV-infected women; studies that used the Nugent criteria for the diagnosis of bacterial vaginosis and studies in which the detection of HPV used the polymerase chain reaction technique. Assembled data, odds ratio (OR) and respective 95% confidence intervals (95%CI) were estimated for the association between bacterial vaginosis and cervical HPV infection using random-effects models. A bilateral value of p < 0.05 was considered statistically significant. RESULT Six studies were selected for analysis and demonstrated association between bacterial vaginosis and cervical HPV infection (OR = 2.68; 95%CI: 1.64-4.40; p < 0.001). CONCLUSION Bacterial vaginosis was considered a risk factor for cervical HPV infection, since women with bacterial vaginosis were more likely to be infected with HPV.
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Affiliation(s)
- Bruno César Teodoro Martins
- Universidade Federal de GoiásFaculdade de MedicinaPrograma de Pós-Graduação em Ciências da SaúdeGoiâniaGOBrasilUniversidade Federal de Goiás. Faculdade de Medicina. Programa de Pós-Graduação em Ciências da Saúde. Goiânia, GO, Brasil
| | - Rafael Alves Guimarães
- Universidade Federal de GoiásFaculdade de EnfermagemPrograma de Pós-Graduação em EnfermagemGoiâniaGOBrasilUniversidade Federal de Goiás. Faculdade de Enfermagem. Programa de Pós-Graduação em Enfermagem. Goiânia, GO, Brasil
| | - Rosane Ribeiro Figueiredo Alves
- Universidade Federal de GoiásFaculdade de MedicinaPrograma de Pós-Graduação em Ciências da SaúdeGoiâniaGOBrasilUniversidade Federal de Goiás. Faculdade de Medicina. Programa de Pós-Graduação em Ciências da Saúde. Goiânia, GO, Brasil
| | - Vera Aparecida Saddi
- Pontifícia Universidade Católica de GoiásPrograma de Pós-Graduação em Ciências Ambientais e da SaúdeGoiâniaGOBrasilPontifícia Universidade Católica de Goiás. Programa de Pós-Graduação em Ciências Ambientais e da Saúde. Goiânia, GO, Brasil
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Lacticaseibacillus rhamnosus Lcr35 Stimulates Epithelial Vaginal Defenses upon Gardnerella vaginalis Infection. Infect Immun 2022; 90:e0030922. [PMID: 36000874 PMCID: PMC9476927 DOI: 10.1128/iai.00309-22] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Dysbiosis of the vaginal microbiome as a result of overgrowth of anaerobic bacteria, such as Gardnerella vaginalis, and low levels of "healthy" lactobacilli leads to bacterial vaginosis (BV), usually associated with a low-grade inflammatory process. Despite appropriate antibiotic treatment, G. vaginalis-associated BV is characterized by significant recurrence. The use of probiotics could be an interesting alternative therapy due to their ability to rebalance vaginal microbiota. In this study, we investigated the effects of a well-characterized probiotic strain, Lacticaseibacillus rhamnosus Lcr35, on epithelial vaginal and dendritic cell (DC) immune responses after G. vaginalis infection. In an in vitro coculture model with human monocyte-derived dendritic cells and a vaginal epithelial cell (VEC) monolayer, the Lcr35 strain induced DC activation, as evidenced by the induction of maturation and synthesis of interleukin-8 (IL-8) and CCL-20 chemokines upon apical challenge of the VECs by G. vaginalis. Analysis of the vaginal epithelial response showed that the presence of Lcr35 significantly increased the production of the proinflammatory cytokines IL-8 and IL-1β and human β-defensin 2 (HBD-2), whereas the concentration of secretory leukocyte protease inhibitor (SLPI) was decreased in G. vaginalis-infected vaginal epithelial cells. Treatment with recombinant SLPI was associated with upregulation of Lcr35-stimulated IL-8 and HBD-2 production. These results suggest that inhibition of SLPI by Lcr35 in vaginal epithelial cells contributes to the host defense response against G. vaginalis infection.
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Gholiof M, Adamson-De Luca E, Wessels JM. The female reproductive tract microbiotas, inflammation, and gynecological conditions. FRONTIERS IN REPRODUCTIVE HEALTH 2022; 4:963752. [PMID: 36303679 PMCID: PMC9580710 DOI: 10.3389/frph.2022.963752] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/07/2022] [Accepted: 07/18/2022] [Indexed: 11/23/2022] Open
Abstract
The intricate interactions between the host cells, bacteria, and immune components that reside in the female reproductive tract (FRT) are essential in maintaining reproductive tract homeostasis. Much of our current knowledge surrounding the FRT microbiota relates to the vaginal microbiota, where ‘health’ has long been associated with low bacterial diversity and Lactobacillus dominance. This concept has recently been challenged as women can have a diverse vaginal microbial composition in the absence of symptomatic disease. The structures of the upper FRT (the endocervix, uterus, Fallopian tubes, and ovaries) have distinct, lower biomass microbiotas than the vagina; however, the existence of permanent microbiotas at these sites is disputed. During homeostasis, a balance exists between the FRT bacteria and the immune system that maintains immune quiescence. Alterations in the bacteria, immune system, or local environment may result in perturbances to the FRT microbiota, defined as dysbiosis. The inflammatory signature of a perturbed or “dysbiotic” FRT microbiota is characterized by elevated concentrations of pro-inflammatory cytokines in cervical and vaginal fluid. It appears that vaginal homeostasis can be disrupted by two different mechanisms: first, a shift toward increased bacterial diversity can trigger vaginal inflammation, and second, local immunity is altered in some manner, which disrupts the microbiota in response to an environmental change. FRT dysbiosis can have negative effects on reproductive health. This review will examine the increasing evidence for the involvement of the FRT microbiotas and inflammation in gynecologic conditions such as endometriosis, infertility, and endometrial and ovarian cancer; however, the precise mechanisms by which bacteria are involved in these conditions remains speculative at present. While only in their infancy, the use of antibiotics and probiotics to therapeutically alter the FRT microbiota is being studied and is discussed herein. Our current understanding of the intimate relationship between immunity and the FRT microbiota is in its early days, and more research is needed to deepen our mechanistic understanding of this relationship and to assess how our present knowledge can be harnessed to assist in diagnosis and treatment of gynecologic conditions.
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Affiliation(s)
- Mahsa Gholiof
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada
| | - Emma Adamson-De Luca
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada
- AIMA Laboratories Inc., Hamilton, ON, Canada
| | - Jocelyn M. Wessels
- Department of Obstetrics and Gynecology, McMaster University, Hamilton, ON, Canada
- AIMA Laboratories Inc., Hamilton, ON, Canada
- *Correspondence: Jocelyn M. Wessels
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7
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Jansåker F, Li X, Knudsen JD, Frimodt-Møller N, Borgfeldt C, Sundquist K. The association between common urogenital infections and cervical neoplasia - A nationwide cohort study of over four million women (2002-2018). THE LANCET REGIONAL HEALTH. EUROPE 2022; 17:100378. [PMID: 35494213 PMCID: PMC9039866 DOI: 10.1016/j.lanepe.2022.100378] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/14/2023]
Abstract
BACKGROUND Cervical cancer is a major cause of mortality and morbidity in women worldwide. This study aimed to estimate the association between common urogenital infections and cervical neoplasia. METHODS A multi-register national cohort study of 4,120,557 women aged ≥15 years (2002-2018) was conducted. The outcomes were cervical cancer and carcinoma in situ (Swedish Cancer Register). The main predictors were urogenital infections-(urinary) cystitis, (bacterial) vaginosis, (candida) vulvovaginitis. Incidence rates per 10,000 person-years were calculated (using the European Standard Population). Cox regression was used to estimate hazard ratios (HR) while adjusting for possible confounders-other genital infections (e.g., cervicitis, salpingitis, urogenital herpes), parity, and sociodemographic factors. FINDINGS In 39·0 million person-years of follow-up, the incidence rate for cervical cancer was 1·2 (95% CI 1·1-1·2) per 10,000 person-years and the figure for cervical carcinoma in situ was more than tenfold higher. The fully adjusted HRs for cervical cancer were 1·31 (95% CI 1·15 and 1·48) and 1·22 (95% CI 1·16 and 1·29) for vaginosis and cystitis, respectively. Vaginosis showed a gradient association to carcinoma in situ. Vulvovaginitis was inversely associated with cervical cancer, but not significantly related with carcinoma in situ in the fully adjusted model. A temporal association with cervical cancer was observed for vaginosis and vulvovaginitis (inversely) but not for cystitis. INTERPRETATION In this large nationwide cohort of women, medically attended common urogenital infections were independently associated with cervical neoplasia, but cystitis was not temporally associated with cervical neoplasia. These findings could be used to increase focus on preventive measures, HPV-vaccination programmes, HPV-analyses- and cervical cancer screening, especially in women suffering from vaginosis. Future studies on the causal mechanism are warranted before generalized public health recommendations can be made. FUNDING Region Skåne, Tore Nilsons Stiftelse, and Swedish Society of Medicine.
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Affiliation(s)
- Filip Jansåker
- Center for Primary Health Care Research, Clinical Research Centre (CRC), Department of Clinical Sciences Malmö, Lund University, Skåne University Hospital, Jan Waldenströms gata 35, Malmö 205 02, Sweden
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | - Xinjun Li
- Center for Primary Health Care Research, Clinical Research Centre (CRC), Department of Clinical Sciences Malmö, Lund University, Skåne University Hospital, Jan Waldenströms gata 35, Malmö 205 02, Sweden
| | - Jenny Dahl Knudsen
- Department of Clinical Microbiology, Rigshospitalet, Copenhagen, Denmark
| | | | - Christer Borgfeldt
- Department of Obstetrics and Gynaecology, Department of Clinical Sciences Lund, Skåne University Hospital, Lund University, Sweden
| | - Kristina Sundquist
- Center for Primary Health Care Research, Clinical Research Centre (CRC), Department of Clinical Sciences Malmö, Lund University, Skåne University Hospital, Jan Waldenströms gata 35, Malmö 205 02, Sweden
- Center for Community-based Healthcare Research and Education (CoHRE), Department of Functional Pathology, School of Medicine, Shimane University, Japan
- Department of Family Medicine and Community Health, Department of Population Health Science and Policy, Icahn School of Medicine at Mount Sinai, NY, USA
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8
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Zhang QQ, Chen R, Li M, Zeng Z, Zhang L, Liao QP. The interplay between microbiota, metabolites, immunity during BV. MEDICINE IN MICROECOLOGY 2022. [DOI: 10.1016/j.medmic.2021.100049] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022] Open
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Wong YP, Cheah FC, Wong KK, Shah SA, Phon SE, Ng BK, Lim PS, Khong TY, Tan GC. Gardnerella vaginalis infection in pregnancy: Effects on placental development and neonatal outcomes. Placenta 2022; 120:79-87. [PMID: 35231793 DOI: 10.1016/j.placenta.2022.02.018] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 11/10/2021] [Revised: 02/06/2022] [Accepted: 02/22/2022] [Indexed: 12/14/2022]
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Mechanistic Insights into Immune Suppression and Evasion in Bacterial Vaginosis. Curr Microbiol 2022; 79:84. [PMID: 35128579 PMCID: PMC8818625 DOI: 10.1007/s00284-022-02771-2] [Citation(s) in RCA: 8] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2021] [Accepted: 01/18/2022] [Indexed: 12/25/2022]
Abstract
The immunological response to bacterial vaginosis (BV) remains poorly understood and recurrent BV is still a major public health burden especially in the pregnant population. This article reviews the potential mechanisms by which BV-associated bacteria suppress and circumvent the host and microbial defence responses, and propagate their survival/dominance without overt inflammation. We discuss the composition of cervicovaginal mucosal barrier and the mechanism by which BV circumvents host defence: the degradation of the mucosal barrier and immunoglobulin A (IgA); the BV-associated organism Gardnerella vaginalis haemolysin (vaginolysin); diminished IgA response against vaginolysin; mucosal sialic acid degradation, foraging and depletion; inhibition of IL-8-induced neutrophilic infiltration; and metabolite-induced incapacitation of neutrophil and monocyte chemotaxis. We also highlight the tolerance/resistance to both host and antimicrobial molecules mounted by BV-associated biofilms. A plausible role of sialic acid-binding immunoglobulin-like lectins (SIGLECS) was also suggested. Sialidase, which is often produced by G. vaginalis, is central to the immunosuppression, relapse and recurrence observed in BV, although it is supported by other hydrolytic enzymes, vaginolysin and immunomodulatory metabolites.
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Dabee S, Passmore JAS, Heffron R, Jaspan HB. The Complex Link between the Female Genital Microbiota, Genital Infections, and Inflammation. Infect Immun 2021; 89:e00487-20. [PMID: 33558324 PMCID: PMC8091093 DOI: 10.1128/iai.00487-20] [Citation(s) in RCA: 20] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023] Open
Abstract
The female genital tract microbiota is part of a complex ecosystem influenced by several physiological, genetic, and behavioral factors. It is uniquely linked to a woman's mucosal immunity and plays a critical role in the regulation of genital inflammation. A vaginal microbiota characterized by a high abundance of lactobacilli and low overall bacterial diversity is associated with lower inflammation. On the other hand, a more diverse microbiota is linked to high mucosal inflammation levels, a compromised genital epithelial barrier, and an increased risk of sexually transmitted infections and other conditions. Several bacterial taxa such as Gardnerella spp., Prevotella spp., Sneathia spp., and Atopobium spp. are well known to have adverse effects; however, the definitive cause of this microbial dysbiosis is yet to be fully elucidated. The aim of this review is to discuss the multiple ways in which the microbiota influences the overall genital inflammatory milieu and to explore the causes and consequences of this inflammatory response. While there is abundant evidence linking a diverse genital microbiota to elevated inflammation, understanding the risk factors and mechanisms through which it affects genital health is essential. A robust appreciation of these factors is important for identifying effective prevention and treatment strategies.
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Affiliation(s)
- Smritee Dabee
- Seattle Children's Research Institute, Seattle, Washington, USA
| | - Jo-Ann S Passmore
- Institute of Infectious Disease and Molecular Medicine (IDM), University of Cape Town, Cape Town, South Africa
- CAPRISA Centre of Excellence in HIV Prevention, University of Cape Town, Cape Town, South Africa
- National Health Laboratory Service, Cape Town, South Africa
| | | | - Heather B Jaspan
- Seattle Children's Research Institute, Seattle, Washington, USA
- Institute of Infectious Disease and Molecular Medicine (IDM), University of Cape Town, Cape Town, South Africa
- University of Washington, Seattle, Washington, USA
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12
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13
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Vargas-Robles D, Morales N, Rodríguez I, Nieves T, Godoy-Vitorino F, Alcaraz LD, Pérez ME, Ravel J, Forney LJ, Domínguez-Bello MG. Changes in the vaginal microbiota across a gradient of urbanization. Sci Rep 2020; 10:12487. [PMID: 32719372 PMCID: PMC7385657 DOI: 10.1038/s41598-020-69111-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/15/2019] [Accepted: 06/17/2020] [Indexed: 12/27/2022] Open
Abstract
The vaginal microbiota of healthy women typically has low diversity, which increases after perturbations. Among these, lifestyle associated with certain sexual and antimicrobial practices may be associated with higher diversity. To test this hypothesis, we characterized the vaginal microbiota in the cervicovaginal and introital sites in sexually active Amerindians (N = 82) spanning urbanization, and in urban mestizos (N = 29), in the Venezuelan Amazonas. HPV status was also considered. Sampling was performed in an urban gradient from remote villages to a town, and women were individually classified by the degree of urbanization (low, medium, and high). Amerindian cervicovaginal and introital microbiota diversity were not associated with major changes in urbanization or ethnicity. There was a non-significant trend of increased diversity with urbanization, with a few taxa found overrepresented in urban Amerindians (Brevibacterium linens and Peptoniphilus lacrimalis) or mestizos (Mobiluncus mulieris and Prevotella sp.). Among all women, cervicovaginal and introital samples clustered, respectively, in four and two community state types (CSTs), where most profiles were dominated by Lactobacillus iners, Gardnerella vaginalis or were highly diverse profiles. HPV status did not associate with microbial diversity. In conclusion, no association was found between urban level and the vaginal microbiome in Amerindian women, and little difference was found between ethnicities. L. iners and high diversity profiles, associated with vaginal health outcomes, prevail in these populations.
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Affiliation(s)
- Daniela Vargas-Robles
- Department of Biology, University of Puerto Rico, San Juan, PR, USA.,Servicio Autónomo Centro Amazónico de Investigación y Control de Enfermedades Tropicales Simón Bolívar, MPPS, Puerto Ayacucho, Venezuela
| | - Natalia Morales
- Servicio Autónomo Centro Amazónico de Investigación y Control de Enfermedades Tropicales Simón Bolívar, MPPS, Puerto Ayacucho, Venezuela
| | - Iveth Rodríguez
- Ministerio del Poder Popular Para La Salud, Caracas, Venezuela
| | - Tahidid Nieves
- Servicio Autónomo Centro Amazónico de Investigación y Control de Enfermedades Tropicales Simón Bolívar, MPPS, Puerto Ayacucho, Venezuela
| | - Filipa Godoy-Vitorino
- Department of Microbiology & Medical Zoology, School of Medicine, University of Puerto Rico, San Juan, PR, USA
| | - Luis David Alcaraz
- Departamento de Biología Celular, Facultad de Ciencias, Universidad Nacional Autónoma de México, Mexico City, Mexico
| | - María-Eglée Pérez
- Department of Mathematics, University of Puerto Rico, San Juan, PR, USA
| | - Jacques Ravel
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, USA
| | - Larry J Forney
- Department of Biological Sciences and the Institute for Bioinformatics and Evolutionary Studies, University of Idaho, Moscow, ID, USA
| | - María Gloria Domínguez-Bello
- Department of Medicine, New York University School of Medicine, New York, USA. .,Departments of Biochemistry and Microbiology and of Anthropology, Rutgers University, New Brunswick, USA.
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Pleckaityte M. Cholesterol-Dependent Cytolysins Produced by Vaginal Bacteria: Certainties and Controversies. Front Cell Infect Microbiol 2020; 9:452. [PMID: 31998661 PMCID: PMC6966277 DOI: 10.3389/fcimb.2019.00452] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2019] [Accepted: 12/12/2019] [Indexed: 01/16/2023] Open
Abstract
Bacterial vaginosis (BV) is a vaginal anaerobic dysbiosis that affects women of reproductive age worldwide. BV is microbiologically characterized by the depletion of vaginal lactobacilli and the overgrowth of anaerobic bacterial species. Accumulated evidence suggests that Gardnerella spp. have a pivotal role among BV-associated bacteria in the initiation and development of BV. However, Gardnerella spp. often colonize healthy women. Lactobacillus iners is considered as a prevalent constituent of healthy vaginal microbiota, and is abundant in BV. Gardnerella spp. and L. iners secrete the toxins vaginolysin (VLY) and inerolysin (INY), which have structural and activity features attributed to cholesterol-dependent cytolysins (CDCs). CDCs are produced by many pathogenic bacteria as virulence factors that participate in various stages of disease progression by forming lytic and non-lytic pores in cell membranes or via pore-independent pathways. VLY is expressed in the majority of Gardnerella spp. isolates; less is known about the prevalence of the gene that encodes INY. INY is a classical CDC; membrane cholesterol acts a receptor for INY. VLY uses human CD59 as its receptor, although cholesterol remains indispensable for VLY pore-forming activity. INY-induced damage of artificial membranes is directly dependent on cholesterol concentration in the bilayer, whereas VLY-induced damage occurs with high levels of membrane cholesterol (>40 mol%). VLY primarily forms membrane-embedded complete rings in the synthetic bilayer, whereas INY forms arciform structures with smaller pore sizes. VLY activity is high at elevated pH, which is characteristic of BV, whereas INY activity is high at more acidic pH, which is specific for a healthy vagina. Increased VLY levels in vaginal mucosa in vivo were associated with clinical indicators of BV. However, experimental evidence is lacking for the specific roles of VLY and INY in BV. The interplay between vaginal bacterial species affects the expression of the gene encoding VLY, thereby modulating the virulence of Gardnerella spp. This review discusses the current evidence for VLY and INY cytolysins, including their structures and activities, factors affecting their expression, and their potential impacts on the progression of anaerobic dysbiosis.
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Affiliation(s)
- Milda Pleckaityte
- Laboratory of Immunology and Cell Biology, Institute of Biotechnology, Life Sciences Center, Vilnius University, Vilnius, Lithuania
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Higher Levels of a Cytotoxic Protein, Vaginolysin, in Lactobacillus-Deficient Community State Types at the Vaginal Mucosa. Sex Transm Dis 2019; 45:e14-e17. [PMID: 29465671 DOI: 10.1097/olq.0000000000000774] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/27/2022]
Abstract
Vaginolysin (VLY), a cytotoxic protein produced by Gardnerella vaginalis, may contribute to bacterial vaginosis. We observed that women with G. vaginalis, low levels of lactobacilli, history of vaginal douching, higher Nugent scores, and higher vaginal pH had increased VLY. Inflammatory markers were not highly expressed with increasing VLY. Vaginolysin's role in bacterial vaginosis warrants further evaluation.
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Sodhani P, Gupta S, Gupta R, Mehrotra R. Bacterial Vaginosis and Cervical Intraepithelial Neoplasia: Is there an Association or is Co-Existence Incidental? Asian Pac J Cancer Prev 2017; 18:1289-1292. [PMID: 28610416 PMCID: PMC5555537 DOI: 10.22034/apjcp.2017.18.5.1289] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022] Open
Abstract
Objectives: To determine associations, if any, of bacterial vaginosis with cervical pre-neoplastic lesions and evaluate any effects of sub-categorization of smears with bacterial vaginosis. Methods: All cervico-vaginal smears reported as positive for bacterial vaginosis over a five-year period were reviewed and sub-categorized into ’type I (dysbacteriosis)’ and ’type II (pure Gardenerella infection)’ smears by two cytopathologists (PS, SG). The proportion of smears with healthy flora and pre-neoplastic lesions was compared with those having bacterial vaginosis in conjunction with such changes. In addition, a comparison was also attempted between the frequencies of pre-neoplastic lesions with the two categories of bacterial vaginosis smears. Results: Bacterial vaginosis was diagnosed in 28.6% (7017 of the 24,565) of the 24,565 smears received in the Institute during the study period. Of these 7,017 smears with bacterial vaginosis, 53% (3717) were categorized as type I and 42.7% (3000) as type II by both cytopathologists. Pre-neoplastic lesions were detected in 10.2% of smears with bacterial vaginosis compared to 5.7% of those with healthy flora (P<0.0001). Of the sub-categories of bacterial vaginosis, the risk of detecting precancerous lesion was higher for type II smears (P<0.001). Conclusion: Sub-categorization of bacterial vaginosis, as performed in the Dutch coding system, may be worthwhile due to the strikingly different risk of associated preneoplasia.
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Affiliation(s)
- Pushpa Sodhani
- Division of Cytopathology, National Institute of Cancer Prevention and Research, Noida, India.
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Smith SB, Ravel J. The vaginal microbiota, host defence and reproductive physiology. J Physiol 2016; 595:451-463. [PMID: 27373840 DOI: 10.1113/jp271694] [Citation(s) in RCA: 198] [Impact Index Per Article: 24.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/19/2015] [Accepted: 01/28/2016] [Indexed: 02/06/2023] Open
Abstract
The interaction between the human host and the vaginal microbiota is highly dynamic. Major changes in the vaginal physiology and microbiota over a woman's lifetime are largely shaped by transitional periods such as puberty, menopause and pregnancy, while daily fluctuations in microbial composition observed through culture-independent studies are more likely to be the results of daily life activities and behaviours. The vaginal microbiota of reproductive-aged women is largely made up of at least five different community state types. Four of these community state types are dominated by lactic-acid producing Lactobacillus spp. while the fifth is commonly composed of anaerobes and strict anaerobes and is sometimes associated with vaginal symptoms. The production of lactic acid has been associated with contributing to the overall health of the vagina due to its direct and indirect effects on pathogens and host defence. Some species associated with non-Lactobacillus vaginal microbiota may trigger immune responses as well as degrade the host mucosa, processes that ultimately increase susceptibility to infections and contribute to negative reproductive outcomes such as infertility and preterm birth. Further studies are needed to better understand the functional underpinnings of how the vaginal microbiota affect host physiology but also how host physiology affects the vaginal microbiota. Understanding this fine-tuned interaction is key to maintaining women's reproductive health.
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Affiliation(s)
- Steven B Smith
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.,Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD, 20742, USA
| | - Jacques Ravel
- Institute for Genome Sciences, University of Maryland School of Medicine, Baltimore, MD, 21201, USA.,Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, MD, 21201, USA
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Krishnamurthy V, Satish S, Vimalambike MG. Cannonballs in Pap Smears: Double Whammy of Bacterial Vaginosis and Associated Infections. Acta Cytol 2016; 60:53-7. [PMID: 26981615 DOI: 10.1159/000444074] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2015] [Accepted: 01/06/2016] [Indexed: 11/19/2022]
Abstract
INTRODUCTION Cannonballs are structures consisting of neutrophils adherent to epithelial cells, often seen in vaginal Pap smears of patients with trichomoniasis and chlamydiasis. We frequently observed these cannonballs in inflammatory Pap smears showing evidence of bacterial vaginosis. OBJECTIVE To study the association between cannonballs and bacterial vaginosis with associated infections in inflammatory Pap smears. STUDY DESIGN This was a retrospective study performed over a period of 6 months between April 2014 and September 2014. Three hundred consecutive Pap smears assessed during the study period were retrieved from the archives and studied. RESULTS A total of 280 smears were studied. Neutrophilic infiltrates were seen in 83.6%, cannonballs in 82.3%, and bacterial vaginosis in 70.7% of the smears. Cannonballs were found in 84.4% of the smears showing evidence of bacterial vaginosis with associated inflammatory infiltrates. There was a significant association between cannonballs and bacterial vaginosis (p = 0.0001). The odds ratio was 13.8 (95% CI: 7.2-26.2). CONCLUSION The present study shows a significant association between cannonballs and bacterial vaginosis and associated vaginal infections.
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Affiliation(s)
- Vani Krishnamurthy
- Department of Pathology, JSS Medical College, JSS University, Mysuru, India
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Slight Pro-Inflammatory Immunomodulation Properties of Dendritic Cells by Gardnerella vaginalis: The "Invisible Man" of Bacterial Vaginosis? J Immunol Res 2016; 2016:9747480. [PMID: 26989700 PMCID: PMC4773579 DOI: 10.1155/2016/9747480] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2015] [Revised: 01/04/2016] [Accepted: 01/10/2016] [Indexed: 12/31/2022] Open
Abstract
Bacterial vaginosis (BV), the most common genital infection in reproductive-aged women, is associated with increased risk of sexually transmitted infections. Its etiology remains unclear, especially the role of Gardnerella (G.) vaginalis, an anaerobic bacterium characteristic of the BV-alteration of the vaginal ecosystem. In the genital mucosa, dendritic cells (DCs) sense bacteria of the microenvironment via receptors and then orchestrate the immune response by induction of different T cell subtypes. We investigated the interactions between G. vaginalis and human monocyte-derived DCs using a wide range of bacterial concentrations (multiplicity of infection from 0.01 to 100), and the effects of this pathogen on PHA-induced lymphocyte proliferation. As observed by electron microscopy and cytometry, G. vaginalis reduced the internalization ability of DCs by forming extracellular clusters and induced neither DC maturation, nor DC secretion of cytokines, except at the highest dose with a very early DC maturation state. The same profile was observed on lymphocytes with significant increases of proliferation and cytokine secretion only at the highest bacterial concentration. Our findings indicate that G. vaginalis possesses slight immune-stimulating activities against DCs and T cells, reflecting thus a defective inflammatory response and giving rise to the atypical, non- or low-grade, inflammatory clinical disease profile.
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de Castro-Sobrinho JM, Rabelo-Santos SH, Fugueiredo-Alves RR, Derchain S, Sarian LOZ, Pitta DR, Campos EA, Zeferino LC. Bacterial vaginosis and inflammatory response showed association with severity of cervical neoplasia in HPV-positive women. Diagn Cytopathol 2015; 44:80-6. [DOI: 10.1002/dc.23388] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2015] [Revised: 09/19/2015] [Accepted: 11/02/2015] [Indexed: 11/06/2022]
Affiliation(s)
| | | | | | - Sophie Derchain
- Department of Obstetrics and Gynecology; State University of Campinas (UNICAMP); Campinas Brazil
| | - Luis Otávio Z Sarian
- Department of Obstetrics and Gynecology; State University of Campinas (UNICAMP); Campinas Brazil
| | - Denise R Pitta
- Department of Obstetrics and Gynecology; State University of Campinas (UNICAMP); Campinas Brazil
| | - Elisabete A Campos
- Department of Obstetrics and Gynecology; State University of Campinas (UNICAMP); Campinas Brazil
| | - Luiz Carlos Zeferino
- Department of Obstetrics and Gynecology; State University of Campinas (UNICAMP); Campinas Brazil
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Is abnormal vaginal microflora a risk factor for intrauterine fetal growth restriction? ASIAN PACIFIC JOURNAL OF REPRODUCTION 2015. [DOI: 10.1016/j.apjr.2015.07.010] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
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Ferreira CST, Marconi C, Parada CMDLG, Duarte MTC, Gonçalves APO, Rudge MVC, da Silva MG. Bacterial vaginosis in pregnant adolescents: proinflammatory cytokine and bacterial sialidase profile. Cross-sectional study. SAO PAULO MED J 2015; 133:465-70. [PMID: 26465813 PMCID: PMC10496559 DOI: 10.1590/1516-3180.2014.9182710] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 06/27/2014] [Revised: 10/21/2014] [Accepted: 10/27/2014] [Indexed: 12/11/2022] Open
Abstract
CONTEXT AND OBJECTIVE Bacterial vaginosis occurs frequently in pregnancy and increases susceptibility to sexually transmitted infections (STI). Considering that adolescents are disproportionally affected by STI, the aim of this study was to evaluate the cervicovaginal levels of interleukin (IL)-1 beta, IL-6, IL-8 and bacterial sialidase in pregnant adolescents with bacterial vaginosis. DESIGN AND SETTING Cross-sectional study at mother and child referral units in Belém, Pará, Brazil. METHODS Vaginal samples from 168 pregnant adolescents enrolled were tested for trichomoniasis and candidiasis. Their vaginal microbiota was classified according to the Nugent criteria (1991) as normal, intermediate or bacterial vaginosis. Cervical infection due to Chlamydia trachomatisand Neisseria gonorrhoeae was also assessed. Cytokine and sialidase levels were measured, respectively, using enzyme-linked immunosorbent assays and MUAN conversion in cervicovaginal lavages. Forty-eight adolescents (28.6%) were excluded because they tested positive for some of the infections investigated. The remaining 120 adolescents were grouped according to vaginal flora type: normal (n = 68) or bacterial vaginosis (n = 52). Their cytokine and sialidase levels were compared between the groups using the Mann-Whitney test (P < 0.05). RESULTS The pregnant adolescents with bacterial vaginosis had higher levels of IL-1 beta, IL-6 and IL-8 (P < 0.05). Sialidase was solely detected in 35 adolescents (67.2%) with bacterial vaginosis. CONCLUSIONS Not only IL-1 beta and sialidase levels, but also IL-6 and IL-8 levels are higher in pregnant adolescents with bacterial vaginosis, thus indicating that this condition elicits a more pronounced inflammatory response in this population, which potentially increases vulnerability to STI acquisition.
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Affiliation(s)
- Carolina Sanitá Tafner Ferreira
- BSc, Master's Student, Department of Pathology, Faculdade de Medicina de Botucatu (FMB), Universidade Estadual Paulista (Unesp), Botucatu, São Paulo, Brazil.
| | - Camila Marconi
- BSc, MSc, PhD. Postdoctoral Fellow. Department of Pathology, Faculdade de Medicina de Botucatu (FMB), Universidade Estadual Paulista (Unesp), Botucatu, São Paulo, Brazil.
| | - Cristina Maria de Lima Garcia Parada
- BSN, MSc, PhD. Adjunct Professor, Department of Nursing, Faculdade de Medicina de Botucatu (FMB), Universidade Estadual Paulista (Unesp), Botucatu, São Paulo, Brazil.
| | - Marli Teresinha Cassamassimo Duarte
- BSN, MSc, PhD. Assistant Professor, Department of Nursing, Faculdade de Medicina de Botucatu (FMB), Universidade Estadual Paulista (Unesp), Botucatu, São Paulo, Brazil
| | | | - Marilza Vieira Cunha Rudge
- MD, MSc, PhD. Titular Professor, Department of Gynecology and Obstetrics, Faculdade de Medicina de Botucatu (FMB), Universidade Estadual Paulista (Unesp), Botucatu, São Paulo, Brazil.
| | - Márcia Guimarães da Silva
- BSc, MSc, PhD. Assistant Professor, Department of Pathology, Faculdade de Medicina de Botucatu (FMB), Universidade Estadual Paulista (Unesp), Botucatu, São Paulo, Brazil.
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Redelinghuys MJ, Ehlers MM, Dreyer AW, Kock MM. Normal flora and bacterial vaginosis in pregnancy: an overview. Crit Rev Microbiol 2015; 42:352-63. [DOI: 10.3109/1040841x.2014.954522] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/12/2022]
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Kovachev SM. Obstetric and gynecological diseases and complications resulting from vaginal dysbacteriosis. MICROBIAL ECOLOGY 2014; 68:173-184. [PMID: 24711012 DOI: 10.1007/s00248-014-0414-5] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/02/2013] [Accepted: 03/24/2014] [Indexed: 06/03/2023]
Abstract
Accurate knowledge of the composition and ecology of vaginal microbial environment of a healthy woman is necessary for the understanding of normal flora and how to reduce the risk for diseases. Vagina and its microflora form a balanced ecosystem in which dominated bacteria are vaginal lactobacilli. There are dynamic changes in this ecosystem having structure and composition depending on many factors. The term dysbacteriosis defines any movement outside the normal range for the given biotope of obligate and/or facultative microflora. Such a change in the quantity and quality of the respective microbial balance is fraught with danger and requires correction and recovery. The purpose of this overview is to examine obstetric and gynecological diseases that can cause vaginal impaired microbial balance. Vaginal dysbacteriosis is a cause, predecessor, and often also consequence of vaginal infections. In essence, any vaginal infection can be seen as dysbacteriosis, developed to the most severe extent. Here, there is a dominant microorganism other than lactic acid bacteria in the vagina (clinically manifested or not, respectively), depletion of defense mechanisms of the vagina associated with the shift of lactobacilli from their dominant role in the vaginal balance, decrease in their number and species diversity, and a resulting change in the healthy status of the vagina. Vaginal dysbacteriosis can be found in pathogenetic mechanism, whereby many obstetric and gynecological diseases develop. Most of these diseases lead directly to increased maternal and infant morbidity and mortality, so it is important to understand the reasons for them and the arrangements for their prevention.
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Affiliation(s)
- Stefan Miladinov Kovachev
- Department of Gynecology, Military Medical Academy, "P.U.Todorov" bul. bl. No. 5, entr. B, fl. No. 25, 1404, Sofia, Bulgaria,
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Krauss-Silva L, Almada-Horta A, Alves MB, Camacho KG, Moreira MEL, Braga A. 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. BMC Pregnancy Childbirth 2014; 14:107. [PMID: 24641730 PMCID: PMC3994593 DOI: 10.1186/1471-2393-14-107] [Citation(s) in RCA: 47] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2013] [Accepted: 03/06/2014] [Indexed: 02/06/2023] Open
Abstract
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.
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Affiliation(s)
- Leticia Krauss-Silva
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, R Leopoldo Bulhões, 1480, room 714, Manguinhos, Rio de Janeiro 21041-210, Brazil.
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Gilbert NM, Lewis WG, Lewis AL. Clinical features of bacterial vaginosis in a murine model of vaginal infection with Gardnerella vaginalis. PLoS One 2013; 8:e59539. [PMID: 23527214 PMCID: PMC3602284 DOI: 10.1371/journal.pone.0059539] [Citation(s) in RCA: 84] [Impact Index Per Article: 7.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/14/2013] [Accepted: 02/15/2013] [Indexed: 02/03/2023] Open
Abstract
Bacterial vaginosis (BV) is a dysbiosis of the vaginal flora characterized by a shift from a Lactobacillus-dominant environment to a polymicrobial mixture including Actinobacteria and Gram-negative bacilli. BV is a common vaginal condition in women and is associated with increased risk of sexually transmitted infection and adverse pregnancy outcomes such as preterm birth. Gardnerella vaginalis is one of the most frequently isolated bacterial species in BV. However, there has been much debate in the literature concerning the contribution of G. vaginalis to the etiology of BV, since it is also present in a significant proportion of healthy women. Here we present a new murine vaginal infection model with a clinical isolate of G. vaginalis. Our data demonstrate that this model displays key features used clinically to diagnose BV, including the presence of sialidase activity and exfoliated epithelial cells with adherent bacteria (reminiscent of clue cells). G. vaginalis was capable of ascending uterine infection, which correlated with the degree of vaginal infection and level of vaginal sialidase activity. The host response to G. vaginalis infection was characterized by robust vaginal epithelial cell exfoliation in the absence of histological inflammation. Our analyses of clinical specimens from women with BV revealed a measureable epithelial exfoliation response compared to women with normal flora, a phenotype that, to our knowledge, is measured here for the first time. The results of this study demonstrate that G. vaginalis is sufficient to cause BV phenotypes and suggest that this organism may contribute to BV etiology and associated complications. This is the first time vaginal infection by a BV associated bacterium in an animal has been shown to parallel the human disease with regard to clinical diagnostic features. Future studies with this model should facilitate investigation of important questions regarding BV etiology, pathogenesis and associated complications.
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Affiliation(s)
- Nicole M. Gilbert
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Warren G. Lewis
- Department of Medicine, Washington University School of Medicine, St. Louis, Missouri, United States of America
| | - Amanda L. Lewis
- Department of Molecular Microbiology, Washington University School of Medicine, St. Louis, Missouri, United States of America
- Department of Obstetrics and Gynecology, Center for Women’s Infectious Disease Research, Washington University School of Medicine, St. Louis, Missouri, United States of America
- * E-mail:
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Gillet E, Meys JFA, Verstraelen H, Verhelst R, De Sutter P, Temmerman M, Broeck DV. Association between bacterial vaginosis and cervical intraepithelial neoplasia: systematic review and meta-analysis. PLoS One 2012; 7:e45201. [PMID: 23056195 PMCID: PMC3462776 DOI: 10.1371/journal.pone.0045201] [Citation(s) in RCA: 101] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 08/17/2012] [Indexed: 11/18/2022] Open
Abstract
OBJECTIVE Bacterial vaginosis (BV), the most common vaginal disorder among women of reproductive age, has been suggested as co-factor in the development of cervical cancer. Previous studies examining the relationship between BV and cervical intra-epithelial neoplasia (CIN) provided inconsistent and conflicting results. The aim of this study is to clarify the association between these two conditions. METHODS A systematic review and meta-analysis were conducted to summarize published literature on the association between BV and cervical pre-cancerous lesions. An extensive search of electronic databases Medline (Pubmed) and Web of Science was performed. The key words 'bacterial vaginosis' and 'bacterial infections and vaginitis' were used in combination with 'cervical intraepithelial neoplasia', 'squamous intraepithelial lesions', 'cervical lesions', 'cervical dysplasia', and 'cervical screening'. Eligible studies required a clear description of diagnostic methods used for detecting both BV and cervical pre-cancerous lesions. Publications were included if they either reported odds ratios (OR) and corresponding 95% confidence intervals (CI) representing the magnitude of association between these two conditions, or presented data that allowed calculation of the OR. RESULTS Out of 329 articles, 17 cross-sectional and 2 incidence studies were selected. In addition, two studies conducted in The Netherlands, using the national KOPAC system, were retained. After testing for heterogeneity and publication bias, meta-analysis and meta-regression were performed, using a random effects model. Although heterogeneity among studies was high (χ(2) = 164.7, p<0.01, I(2) = 88.5), a positive association between BV and cervical pre-cancerous lesions was found, with an overall estimated odds ratio of 1.51 (95% CI, 1.24-1.83). Meta-regression analysis could not detect a significant difference between studies based on BV diagnosis, CIN diagnosis or study population. CONCLUSIONS Although most studies were cross-sectional and heterogeneity was high, this meta-analysis confirms a connection between BV and CIN.
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Affiliation(s)
- Evy Gillet
- International Centre for Reproductive Health (ICRH), Ghent University, Ghent, Belgium
- Department of Gynaecology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Joris F. A. Meys
- Department of Applied Mathematics, Biometrics and Process Control, Faculty of Bioscience Engineering, Ghent University, Ghent, Belgium
| | - Hans Verstraelen
- Department of Obstetrics and Gynaecology, Ghent University Hospital, Ghent, Belgium
| | - Rita Verhelst
- International Centre for Reproductive Health (ICRH), Ghent University, Ghent, Belgium
| | - Philippe De Sutter
- Department of Gynaecology, Vrije Universiteit Brussel, Brussels, Belgium
| | - Marleen Temmerman
- International Centre for Reproductive Health (ICRH), Ghent University, Ghent, Belgium
| | - Davy Vanden Broeck
- International Centre for Reproductive Health (ICRH), Ghent University, Ghent, Belgium
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Cetin I, Pileri P, Villa A, Calabrese S, Ottolenghi L, Abati S. Pathogenic mechanisms linking periodontal diseases with adverse pregnancy outcomes. Reprod Sci 2012; 19:633-41. [PMID: 22421445 DOI: 10.1177/1933719111432871] [Citation(s) in RCA: 28] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
In the last 2 decades, a large proportion of studies have focused on the relationship between maternal periodontal disease and poor obstetric outcomes. The aim of the present review is to summarize the current knowledge about human studies on the pathogenetic mechanisms linking periodontal diseases with adverse pregnancy outcomes. A search of the medical literature was conducted using NIH (National Institute of Health) Pubmed through April 2011. Articles were identified with the Medical Subject Heading (MeSH) and free text terms "small for gestational age (SGA)," "preeclampsia," "preterm labor," and "periodontal disease." Experimental human studies have shown that periodontal pathogens may disseminate toward placental and fetal tissues accompanied by an increase in inflammatory mediators in the placenta. As such, new inflammatory reactions within the placental tissues of the pregnant woman may occur, the physiological levels of prostaglandin E(2) (PGE(2)) and tumor necrosis factor-α (TNF-α) in the amniotic fluid may increase and eventually lead to premature delivery. Although many data from clinical trials suggest that periodontal disease may increase the adverse pregnancy outcome, the exact pathogenetic mechanism involved remains controversial. The findings explain the potential link between periodontal infections and adverse pregnancy outcomes. First, periodontal bacteria can directly cause infections both of the uteroplacenta and the fetus; second, systemic inflammatory changes induced by periodontal diseases can activate responses at the maternal-fetal interface. Of note, associative studies have produced different results in different population groups and no conclusive evidence has still been produced for the potential role of preventive periodontal care to reduce the risk factors of preterm birth.
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Affiliation(s)
- I Cetin
- Unit of Obstetrics and Gynecology, Department of Clinical Sciences L. Sacco, and Center for Fetal Research Giorgio Pardi, University of Milan, Milan, Italy.
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Krauss-Silva L, Moreira MEL, Alves MB, Braga A, Camacho KG, Batista MRR, Almada-Horta A, Rebello MR, Guerra F. A randomised controlled trial of probiotics for the prevention of spontaneous preterm delivery associated with bacterial vaginosis: preliminary results. Trials 2011; 12:239. [PMID: 22059409 PMCID: PMC3264514 DOI: 10.1186/1745-6215-12-239] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Accepted: 11/08/2011] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Bacterial vaginosis increases the risk of spontaneous preterm delivery at less than 34 weeks of gestation. OBJECTIVE The purpose of this study was to evaluate the efficacy of the early administration of selected lactobacilli strains (probiotics) to pregnant women with asymptomatic bacterial vaginosis/intermediate-degree infections to prevent spontaneous premature delivery and associated neonatal morbidity. METHODS/DESIGN Asymptomatic pregnant women at less than 20 weeks of gestation, with no indication of elective preterm delivery, with a vaginal pH ≥ 4.5 and Nugent score > 3 were randomly assigned to the placebo or intervention group (oral administration of selected lactobacilli up to the 24th to 26th week of gestation). The randomisation was stratified for the history of premature delivery (HPD) and blocked. The allocation was concealed, and the participating health professionals and patients were blinded. The primary outcome was preterm delivery (<34 to <32 weeks), and the secondary outcomes were associated neonatal complications. RESULTS In total, 4,204 pregnant women were screened; 320 and 324 individuals were respectively randomly assigned to the placebo and intervention groups, and 62% finished the trial. None of the randomised patients were lost to follow-up. For the non-HPD stratum, the intent-to-treat relative risks of spontaneous premature birth at < 34 and < 37 weeks' gestation were 0.33 (0.03, 3.16) and 0.49 (0.17, 1.44), respectively, and they were non-significant (ns) with p = 0.31 and 0.14. The corresponding actual treatment figures were zero and 0.32 (0.09, 1.19), which were ns with p = 0.12 and 0.06. The intent-to-treat relative risk of spontaneous premature birth at < 37 weeks of gestation for the trial as a whole, including HPD and non-HPD participants, was 0.69 (0.26, 1.78), p = 0.30 (ns). The neonatal complications under evaluation occurred in only one infant (< 34 weeks; placebo group) who presented with respiratory distress syndrome and suspected early neonatal sepsis. The recorded adverse events were minor and relatively non-specific. CONCLUSIONS The efficacy of the tested probiotics to prevent preterm delivery among women without a history of preterm delivery was not determined because the study sample was insufficient to estimate statistically significant intent-to-treat effects; additional studies are needed to evaluate this intervention among these women. TRIAL REGISTRATION Trial registration at NIH register: NCT00303082. Sources of funding: the Brazilian Health Ministry and the State of Rio de Janeiro Research Foundation.
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Affiliation(s)
- Leticia Krauss-Silva
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
| | - Maria Elizabeth L Moreira
- Clinical Research Unit, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
| | - Mariane B Alves
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
- Institute of Mathematics, Federal University in Rio de Janeiro, Av. Athos da Silveira Ramos - 149, Rio de Janeiro, 21941-909, Brazil
| | - Alcione Braga
- PROCEP, Pró-Cardíaco, R. General Polidoro, 142, Rio de Janeiro, 22280-003, Brazil
| | - Karla G Camacho
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
| | - Maria Rosa R Batista
- Department of Obstetrics and Gynecology, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
| | - Antonio Almada-Horta
- Federal University in Rio de Janeiro Medical School, Av. Brigadeiro Trompowski, Rio de Janeiro, 21044-020, Brazil
| | - Maria R Rebello
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
| | - Fernando Guerra
- Department of Obstetrics and Gynecology, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
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Rampersaud R, Planet PJ, Randis TM, Kulkarni R, Aguilar JL, Lehrer RI, Ratner AJ. Inerolysin, a cholesterol-dependent cytolysin produced by Lactobacillus iners. J Bacteriol 2011; 193:1034-41. [PMID: 21169489 PMCID: PMC3067590 DOI: 10.1128/jb.00694-10] [Citation(s) in RCA: 94] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/15/2010] [Accepted: 11/30/2010] [Indexed: 11/20/2022] Open
Abstract
Lactobacillus iners is a common constituent of the human vaginal microbiota. This species was only recently characterized due to its fastidious growth requirements and has been hypothesized to play a role in the pathogenesis of bacterial vaginosis. Here we present the identification and molecular characterization of a protein toxin produced by L. iners. The L. iners genome encodes an open reading frame with significant primary sequence similarity to intermedilysin (ILY; 69.2% similarity) and vaginolysin (VLY; 68.4% similarity), the cholesterol-dependent cytolysins from Streptococcus intermedius and Gardnerella vaginalis, respectively. Clinical isolates of L. iners produce this protein, inerolysin (INY), during growth in vitro, as assessed by Western analysis. INY is a pore-forming toxin that is activated by reducing agents and inhibited by excess cholesterol. It is active across a pH range of 4.5 to 6.0 but is inactive at pH 7.4. At sublytic concentrations, INY activates p38 mitogen-activated protein kinase and allows entry of fluorescent phalloidin into the cytoplasm of epithelial cells. Unlike VLY and ILY, which are human specific, INY is active against cells from a broad range of species. INY represents a new target for studies directed at understanding the role of L. iners in states of health and disease at the vaginal mucosal surface.
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Affiliation(s)
- Ryan Rampersaud
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
| | - Paul J. Planet
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
| | - Tara M. Randis
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
| | - Ritwij Kulkarni
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
| | - Jorge L. Aguilar
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
| | - Robert I. Lehrer
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
| | - Adam J. Ratner
- Departments of Pediatrics, Microbiology and Immunology, Columbia University, New York, New York 10032, Department of Medicine, University of California—Los Angeles, Los Angeles, California 90095
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High sialidase levels increase preterm birth risk among women who are bacterial vaginosis-positive in early gestation. Am J Obstet Gynecol 2011; 204:142.e1-9. [PMID: 21055720 DOI: 10.1016/j.ajog.2010.08.061] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2010] [Revised: 07/21/2010] [Accepted: 08/20/2010] [Indexed: 11/20/2022]
Abstract
OBJECTIVE The purpose of this study was to assess whether vaginal sialidases level in early pregnancy is associated with preterm birth among women who are bacterial vaginosis-positive. STUDY DESIGN Of the 1806 women who were enrolled at < 20 weeks of gestation, 800 of the women were bacterial vaginosis-positive (Nugent score, 7-10); 707 of the women had birth outcome data; 109 of the women who were bacterial vaginosis-positive had an adverse preterm outcome, which included 53 spontaneous preterm births (19 births were early at 20-34 weeks, and 34 births were late at 34-37 weeks), and 14 of the women had late miscarriages (12-20 weeks). Sialidase levels were compared with 352 control subjects (term normal birthweight infants). RESULTS Sialidase levels at ≥ 5, ≥ 10, and ≥ 14 nmol (odds ratio [OR], 1.56; 95% confidence interval [CI], 1.01-2.41; OR, 2.14; 95% CI, 1.25-3.64; OR, 3.17; 95% CI, 1.64-6.10, respectively) was associated significantly with all adverse preterm outcomes. The ≥ 10 nmol and ≥ 14 nmol cut-points were associated strongly with early spontaneous preterm births (OR, 3.79; 95% CI, 1.42-10.10 and OR, 5.36; 95% CI, 1.77-16.23, respectively) and late miscarriages (OR, 4.87; 95% CI, 1.61-14.65; OR, 8.33; 95% CI, 2.57-26.9, respectively). CONCLUSION Elevated sialidase level that is measured at 12 weeks of gestation is associated strongly with early spontaneous preterm births and late miscarriage.
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Gillet E, Meys JF, Verstraelen H, Bosire C, De Sutter P, Temmerman M, Broeck DV. Bacterial vaginosis is associated with uterine cervical human papillomavirus infection: a meta-analysis. BMC Infect Dis 2011; 11:10. [PMID: 21223574 PMCID: PMC3023697 DOI: 10.1186/1471-2334-11-10] [Citation(s) in RCA: 196] [Impact Index Per Article: 15.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2010] [Accepted: 01/11/2011] [Indexed: 02/07/2023] Open
Abstract
Background Bacterial vaginosis (BV), an alteration of vaginal flora involving a decrease in Lactobacilli and predominance of anaerobic bacteria, is among the most common cause of vaginal complaints for women of childbearing age. It is well known that BV has an influence in acquisition of certain genital infections. However, association between BV and cervical human papillomavirus (HPV) infection has been inconsistent among studies. The objective of this meta-analysis of published studies is to clarify and summarize published literature on the extent to which BV is associated with cervical HPV infection. Methods Medline and Web of Science were systematically searched for eligible publications until December 2009. Articles were selected based on inclusion and exclusion criteria. After testing heterogeneity of studies, meta-analysis was performed using random effect model. Results Twelve eligible studies were selected to review the association between BV and HPV, including a total of 6,372 women. The pooled prevalence of BV was 32%. The overall estimated odds ratio (OR) showed a positive association between BV and cervical HPV infection (OR, 1.43; 95% confidence interval, 1.11-1.84). Conclusion This meta-analysis of available literature resulted in a positive association between BV and uterine cervical HPV infection.
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Affiliation(s)
- Evy Gillet
- International Centre for Reproductive Health (ICRH), Ghent University, Ghent, Belgium
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Zabor EC, Klebanoff M, Yu K, Zhang J, Nansel T, Andrews W, Schwebke J, Jeffcoat M. Association between periodontal disease, bacterial vaginosis, and sexual risk behaviours. J Clin Periodontol 2010; 37:888-93. [PMID: 20636412 PMCID: PMC2962875 DOI: 10.1111/j.1600-051x.2010.01593.x] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/19/2022]
Abstract
BACKGROUND Both periodontal disease and bacterial vaginosis may cause adverse pregnancy outcomes. This study evaluated the association between periodontal disease and bacterial vaginosis. MATERIALS AND METHODS Data from 3569 women enrolled in the Longitudinal Study of Vaginal Flora were used. Periodontal disease, defined as greater than three sites with ≥4 mm attachment loss, was assessed by specially calibrated hygienists at baseline. Positive bacterial vaginosis status was based on a Nugent Gram stain score ≥7. Pairs of independent variables were compared with Pearson's χ(2) and risk ratios were calculated through log-binomial regression. RESULTS Twenty-eight per cent of women with bacterial vaginosis had periodontal disease compared with 22% without , corresponding to 1.29 (95% CI: 1.13, 1.47) times greater risk of periodontal disease among women with bacterial vaginosis. In adjusted analysis the risk ratio dropped to 1.23 (95% CI: 1.08, 1.40). Receptive oral sex with an uncircumcised partner was associated with 1.28 times (95% CI: 0.97, 1.69) the risk for periodontal disease compared with receptive oral sex with a circumcised partner, though the association is not statistically significant. CONCLUSIONS In this population, there is a small but significant association between periodontal disease and bacterial vaginosis and a possible trend between receptive oral sex with an uncircumcised partner and periodontal disease.
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Affiliation(s)
- Emily Craig Zabor
- Division of Biostatistics, University of Minnesota, Minneapolis, MN, USA.
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Krauss-Silva L, Moreira MEL, Alves MB, Rezende MR, Braga A, Camacho KG, Batista MRR, Savastano C, Almada-Horta A, Guerra F. Randomized controlled trial of probiotics for the prevention of spontaneous preterm delivery associated with intrauterine infection: study protocol. Reprod Health 2010; 7:14. [PMID: 20591191 PMCID: PMC2911410 DOI: 10.1186/1742-4755-7-14] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2010] [Accepted: 06/30/2010] [Indexed: 12/02/2022] Open
Abstract
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.
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Affiliation(s)
- Leticia Krauss-Silva
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
| | - Maria Elizabeth L Moreira
- Clinical Research Unit, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
| | - Mariane B Alves
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
- Institute of Mathematics, Federal University of Rio de Janeiro, Av. Athos da Silveira Ramos - 149, Rio de Janeiro, 21941-909, Brazil
| | - Maria R Rezende
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
| | - Alcione Braga
- PROCEP, Pró-Cardíaco, R. General Polidoro, 142, Rio de Janeiro, 22280-003, Brazil
| | - Karla G Camacho
- Health Technology Assessment Unit, National School of Public Health, Oswaldo Cruz Foundation, Brazilian Health Ministry, Brazil, R. Leopoldo Bulhões, 1480, Rio de Janeiro, 21041-210, Brazil
| | - Maria Rosa R Batista
- Department of Obstetrics and Gynecology, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
| | - Clarisse Savastano
- Clinical Research Unit, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
| | - Antonio Almada-Horta
- Federal University of Rio de Janeiro Medical School, Av. Brigadeiro Trompowski, Rio de Janeiro, 21044-020, Brazil
| | - Fernando Guerra
- Department of Obstetrics and Gynecology, Fernandes Figueira Institute, Oswaldo Cruz Foundation, Brazilian Health Ministry, Av. Rui Barbosa, 716, Rio de Janeiro, 22250-020, Brazil
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Srinivasan U, Misra D, Marazita ML, Foxman B. Vaginal and oral microbes, host genotype and preterm birth. Med Hypotheses 2009; 73:963-75. [PMID: 19942083 PMCID: PMC4026093 DOI: 10.1016/j.mehy.2009.06.017] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/03/2009] [Revised: 06/03/2009] [Accepted: 06/06/2009] [Indexed: 01/08/2023]
Abstract
Preterm birth (PTB) is a leading cause of infant mortality and morbidity in the US and across the globe. Infection and associated inflammation are important initiators for PTB pathways; an estimated 40% of PTBs are attributed to amniochorionic-decidual or systemic inflammation. Historically, intrauterine infections have been implicated in PTB; recent evidence suggests that infections remote from the fetal site may also be causative. There is strong epidemiological evidence that bacterial vaginosis and periodontitis--two syndromes characterized by perturbations in the normal vaginal and oral bacterial microflora, respectively--are linked to infection-associated PTB. Oral and vaginal environments are similar in their bacterial microbiology; identical bacterial species have been independently isolated in periodontitis and bacterial vaginosis. Periodontitis and bacterial vaginosis also share many behavioral and sociodemographic risk factors suggesting a possible common pathophysiology. Genetic polymorphisms in host inflammatory responses to infection are shared between bacterial vaginosis, periodontitis and PTB, suggesting common mechanisms through which host genotype modify the effect of abnormal bacterial colonization on preterm birth. We review the state of knowledge regarding the risk of PTB attributable to perturbations in bacterial flora in oral and vaginal sites and the role of host genetics in modifying the risk of infection-related PTB. We posit that bacterial species that are common in perturbed vaginal and oral sites are associated with PTB through their interaction with the host immune system.
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Affiliation(s)
- Usha Srinivasan
- Department of Epidemiology, School of Public Health, University of Michigan, Ann Arbor, MI, USA.
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Cauci S, Culhane JF, Di Santolo M, McCollum K. Among pregnant women with bacterial vaginosis, the hydrolytic enzymes sialidase and prolidase are positively associated with interleukin-1beta. Am J Obstet Gynecol 2008; 198:132.e1-7. [PMID: 17714681 DOI: 10.1016/j.ajog.2007.05.035] [Citation(s) in RCA: 55] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/24/2006] [Revised: 03/09/2007] [Accepted: 05/22/2007] [Indexed: 11/23/2022]
Abstract
OBJECTIVE The objective of the study was to explore the mechanisms of local innate immunity induction and modulation in pregnant women with bacterial vaginosis (BV). STUDY DESIGN A total of 200 singleton pregnant women in early gestation (12 +/- 4 weeks) with BV (Nugent 7-10) without concurrent vaginal infections with Trichomonas vaginalis, Chlamydia trachomatis, Neisseria gonorrhoeae, syphilis, and yeast. Concentrations of vaginal interleukin (IL)-1beta and IL-8, the number of neutrophils, and the levels of sialidase and prolidase hydrolytic enzymes were determined in vaginal fluid. RESULTS Concentrations of vaginal IL-1beta had a strong positive correlation with levels of sialidase (P < .001) and prolidase (P < .001). Conversely, such enzymes were negatively correlated with the ratio of IL-8/IL-1beta (both P < .001) and were not significantly associated with concentrations of IL-8. Notably, the number of vaginal neutrophils had a negative correlation with sialidase (P = .007). CONCLUSION The strong induction of IL-1beta in BV-positive women appears to be associated with the production of the hydrolytic enzymes sialidase and prolidase by BV-associated bacteria. However, these 2 enzymes may inhibit the expected amplification of the proinflammatory IL-1beta cascade as evaluated by the down-regulation of the IL-8/IL-1beta ratio. A blunted response to IL-1beta signals may cause the poor rise of neutrophils, which is peculiar to BV. This impairment of local defense may contribute to increased susceptibility to adverse outcomes in BV-positive pregnant women.
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Affiliation(s)
- Sabina Cauci
- Department of Biomedical Sciences and Technologies, University of Udine School of Medicine, Udine, Italy.
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Abstract
Studying the vaginal microflora is not only fascinating, with many discoveries to be made, it is also a very practical way to help women get rid of bothersome and sometimes dangerous infections. Gram-stained vaginal preparations, Pap smears, specific cultures, and nucleic acid detection techniques can be used to diagnose the constituents of the vaginal flora, but in trained hands office-based microscopy of a fresh vaginal smear, preferably using a x400 magnification phase-contrast microscope, allows almost every diagnosis and combination of diagnoses imaginable. In this chapter I will address the pros and cons of the tools that are in use to study vaginal flora, and discuss the different types of bacterial flora and the difficulties encountered in reaching the correct diagnosis of pathological conditions. The 'intermediate flora' is addressed separately, and a new entity--'aerobic vaginitis'--is discussed. Future research should focus on the interaction between infecting microorganisms and host defence mechanisms, as both together generate the pathogenicity of these conditions.
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Cauci S, Di Santolo M, Casabellata G, Ryckman K, Williams SM, Guaschino S. Association of interleukin-1beta and interleukin-1 receptor antagonist polymorphisms with bacterial vaginosis in non-pregnant Italian women. Mol Hum Reprod 2007; 13:243-50. [PMID: 17314118 DOI: 10.1093/molehr/gam002] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
Bacterial vaginosis (BV) is the most prevalent alteration of vaginal microflora worldwide. BV is a polymicrobial disorder, and its etiology is elusive. Factors predisposing to this recurrent condition are not fully characterized. We aimed to investigate whether interleukin-1beta (IL-1beta) and IL-1 receptor antagonist (IL-1ra) polymorphisms are associated with BV in non-pregnant white Italian women. Genomic DNA was obtained from 164 BV positive, and 406 control women. Two diallelic polymorphisms in the IL-1beta gene (IL-1B) representing C/T base transitions at - 511 and + 3954 positions and a variable number tandem repeats (VNTR) in intron 2 of the IL-1ra gene (IL-1RN) were assessed. We demonstrated that women who were homozygous for - 511 CC or + 3954 TT of the IL-1B gene were at increased risk for BV with an odds ratio (OR) = 1.5 [95% confidence interval (CI) = 1.03-2.14, P = 0.032], and OR = 2.8 (95% CI = 1.37-5.88, P = 0.004), respectively. The haplotype - 511/ + 3954 T-C was protective for BV, with an OR = 0.7 (95% CI = 0.49-0.90, P = 0.009). The IL-1RN VNTR genotype was not associated with BV, although the rare allele 3 showed a trend towards protection (P = 0.049). These data show that host genetic variants at the IL-1beta locus predispose to BV among Caucasian non-pregnant women. Further studies will determine whether these genetic polymorphisms modulate the risk for BV recurrence, and/or BV associated severe adverse outcomes as preterm birth and human immunodeficiency virus transmission.
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Affiliation(s)
- Sabina Cauci
- Department of Biomedical Sciences and Technologies, School of Medicine, University of Udine, Udine, Italy.
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Cauci S, Culhane JF. Modulation of vaginal immune response among pregnant women with bacterial vaginosis by Trichomonas vaginalis, Chlamydia trachomatis, Neisseria gonorrhoeae, and yeast. Am J Obstet Gynecol 2007; 196:133.e1-7. [PMID: 17306653 DOI: 10.1016/j.ajog.2006.08.033] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2006] [Revised: 06/15/2006] [Accepted: 08/08/2006] [Indexed: 02/03/2023]
Abstract
OBJECTIVE This study was undertaken to examine the influence of coinfections on vaginal innate and adaptive immunity, and microbial enzyme activities of pregnant women with bacterial vaginosis (BV). STUDY DESIGN The population consisted of 265 singleton pregnant women in early gestation (<20 weeks) with BV (Nugent 7-10) who had vaginal fluid collected for measurement of interleukin-1beta (IL-1beta) and IL-8 concentrations, number of neutrophils, immunoglobulin A against Gardnerella vaginalis (anti-Gvh IgA), and activities of microbial sialidase and prolidase. RESULTS Among women with BV, median levels of vaginal IL-1beta (4-fold, P = .005), IL-8 (4-fold, P < .001), and neutrophils (6-fold, P = .013) were greatly increased in women with T vaginalis with respect to women without any coinfection. Yeast increased the level of IL-8 (5-fold, P < .001), but not IL-1beta (P = .239) and neutrophils (P = .060). Chlamydia trachomatis and Neisseria gonorrhoeae had no effect on vaginal cytokines. None of the coinfections influenced vaginal anti-Gvh IgA, sialidase and prolidase activities. CONCLUSION The strong proinflammatory cytokine induction by T. vaginalis may contribute to the observed increase in preterm birth among BV positive women coinfected with T. vaginalis treated with metronidazole.
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Affiliation(s)
- Sabina Cauci
- Department of Biomedical Sciences and Technologies, School of Medicine, University of Udine, Italy.
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Culhane JF, Nyirjesy P, McCollum K, Goldenberg RL, Gelber SE, Cauci S. Variation in vaginal immune parameters and microbial hydrolytic enzymes in bacterial vaginosis positive pregnant women with and without Mobiluncus species. Am J Obstet Gynecol 2006; 195:516-21. [PMID: 16643824 DOI: 10.1016/j.ajog.2006.02.036] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/22/2005] [Revised: 01/30/2006] [Accepted: 02/26/2006] [Indexed: 11/30/2022]
Abstract
OBJECTIVE This study was undertaken to assess if levels of interleukin-1beta (IL-1beta), IL-8, sialidase, prolidase and immunoglobulin A against Gardenerella vaginalis hemolysin (anti-Gvh IgA) in vaginal secretions differ between BV+ women with (M+) and without (M-) Mobiluncus spp. STUDY DESIGN Vaginal secretions were obtained from 265 women at their first prenatal care visit and assessed for all study parameters. Gram stain evaluation using Nugent criteria was performed and coinfection with sexually transmitted infections determined. Differences between BV+/M+ and BV+/M- women were evaluated using the chi2 statistic or Mann-Whitney test. RESULTS Of the 265 BV+ women, 43% (n = 113) were M+ of which 97% (n = 110) had Nugent scores of 9 or 10 . BV+/M+ women had elevated levels of sialidase (median value: 4.11 nmol vs 1.91 nmol of converted substrate; P = .003) but no difference in prolidase, anti-Gvh IgA, IL-1beta, IL-8, levels were found between the two groups. BV+/M- women had significantly higher rates of coinfection with Trichomonas vaginalis. CONCLUSION BV+/M+ women have higher vaginal concentrations of sialidase and lower rates of T. vaginalis compared with BV+/M- women. Further research is needed to assess the association of this, and other, microbiologic profiles to risk of adverse pregnancy outcome.
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Affiliation(s)
- Jennifer F Culhane
- Department of Obstetrics and Gynecology, Drexel University College of Medicine, Philadelphia, PA 19102, USA.
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SIBioC 2006 38th National Congress of the Italian Society of Clinical Biochemistry and Clinical Molecular Biology, Turin, Italy, September 19–22, 2006. Clin Chem Lab Med 2006. [DOI: 10.1515/cclm.2006.230] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
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Sawada M, Otsuki K, Mitsukawa K, Yakuwa K, Nagatsuka M, Okai T. Cervical inflammatory cytokines and other markers in the cervical mucus of pregnant women with lower genital tract infection. Int J Gynaecol Obstet 2005; 92:117-21. [PMID: 16307744 DOI: 10.1016/j.ijgo.2005.10.004] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/01/2005] [Revised: 10/02/2005] [Accepted: 10/12/2005] [Indexed: 10/25/2022]
Abstract
OBJECTIVE To evaluate concentrations of interleukin (IL)-6, IL-8, lactoferrin (LF), and alpha defencine (alpha-DF) in the cervical mucus of pregnant women and analyze their relation to cervicitis and bacterial vaginosis (BV). METHODS Cervical mucus samples were obtained from August 2003 through May 2004 from 157 women who were between the 6th and 36th week of an uncomplicated singleton pregnancy. All women were delivered at term, 69 without BV or cervicitis, 9 with BV, and 79 with cervicitis. RESULTS Interleukin 8, LF, and mu-DF concentrations were higher in women with cervicitis (0.81 +/- 0.36 pg/mL, 14.8+/-12.3 microg/mL, and 0.60 +/- 0.49 microg/mL) than in women without BV or cervicitis (0.35 +/- 0.34 pg/mL, 8.0 +/- 11.0 microg/mL, and 0.15 +/- 0.12 microg/mL). Interleukin 6 concentration was higher in women with BV (0.26 +/- 0.32 pg/mL) than in women without BV or cervicitis (0.09 +/- 0.15 pg/mL) or in women with cervicitis (0.12 +/- 0.18 pg/mL). CONCLUSIONS Higher levels of inflammatory cytokines in the cervical mucus of pregnant women may lead to early detection of lower genital tract infection.
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Affiliation(s)
- M Sawada
- Department of Obstetrics and Gynecology, Showa University School of Medicine, Shinagawa-ku, Tokyo, Japan
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Abstract
The use of biochemical profiles and new molecular microbiologic methodologies is transforming our understanding of BV. Most important is the recognition of different subgroups of women who have BV who are at variable risk of certain obstetric and gynecologic complications. New diagnostic tests may soon be available that will allow women to test self-obtained specimens. Treatment of BV has lagged, although innovative methods appear to be helpful in managing recurrent diseases.
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Affiliation(s)
- Jack D Sobel
- Harper University Hospital, Division of Infectious Diseases, 3990 John R-5 Hudson, Detroit, MI 48201, USA.
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Reid G, Anand S, Bingham MO, Mbugua G, Wadstrom T, Fuller R, Anukam K, Katsivo M. Probiotics for the developing world. J Clin Gastroenterol 2005; 39:485-8. [PMID: 15942433 DOI: 10.1097/01.mcg.0000165648.32371.38] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Every minute of every day more and more children die of diarrheal diseases and women, and girls become infected by HIV. An estimated 7,000 women become infected each day. While many valiant efforts are being made to address these issues, until now they have proved to be markedly ineffective. The notion that lactic acid bacteria, formulated into food or dietary supplements, could have a role to play in slowing the morbidity and mortality associated with HIV/AIDS and gastroenteritis, is built upon sound clinical findings and scientific investigations, yet no international efforts have been placed in this approach, to date. We hereby summarize the reasons why such efforts should be made, provide an example of one model being set up in sub-Saharan Africa, and challenge the international community to consider the potential benefits of probiotics, especially for communities not reached by governmental and nongovernmental agencies.
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Affiliation(s)
- Gregor Reid
- Canadian Research and Development Centre for Probiotics, Lawson Health Research Institute, London, Ontario, Canada.
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