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

Abstract

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

The Human Microbiome during Bacterial Vaginosis

“…vaginalis has shown high sensitivity (100%) but low specificity (49%) for BV. It is often detected in the absence of BV as well as in both sexually inexperienced and experienced women (54,55). Numerous studies have confirmed the presence of G. vaginalis not only in women with BV but also in women without BV, via both conventional culture techniques and molecular-based studies (11,56).…”

“…Both culture-and DNA-based studies have detected these genera in both women with and those without BV (4,9,14,20,54,57,82,87). Delaney and Onderdonk reported that the bacterial concentration of Peptostreptococcus increased significantly as the total Nugent score increased.…”

“…An additional symbiotic relationship between Prevotella and Peptostreptococcus anaerobius was reported, where amino acids produced by Prevotella enhanced the growth of P. anaerobius (89). In addition to these polyamines, Prevotella species such as P. bivia and P. disiens produce collagenase and fibrinolysins, which can degrade the mucosal surface and promote the detachment of vaginal epithelial cells, and sialidase and prolidases, which lead to vaginal sloughing (54).…”

Dental Caries: A Microbiological Approach

“…Bacterial vaginosis is more frequent in females with bacterial infection of caries [35]. Total spending on dental services in the United States will be over $65 billion this year, with arguably about half of this a direct or indirect result of dental caries [36].…”

Chronic Inflammation in the Epidermis: A Mathematical Model

“…Dysbiosis is broadly observed for several microbial ecologies, including in aquatic systems or intestinal systems. It has been shown to be associated with illnesses, such as cancer [30,31], bacterial vaginosis [32], inflammatory bowel disease [33,34], chronic fatigue syndrome [35], obesity [36,37] and colitis [38]. Dysbiosis in the gut is known to be associated with major chronic inflammation states [39].…”