Garnerella vaginalis bacteremia after vaginal myomectomy

A case report of septic gardnerellosis

Gardnerella vaginalis is a bacterium that is found as the most common cause of bacterial vaginitis in women. In this paper, we describe a case report of a 22-years old woman infected with G. vaginalis, who was initially suspected to have Dengue fever. The similarity of clinical symptoms developed by this disease with the symptoms of some other tropical infectious diseases, as well as a travel history, complicated identification of the disease cause for this particular patient. Here, we present a detailed epidemiological and clinical description of this case, leading to a final diagnosis of a septic form of gardnerellosis.

Gardnerella and vaginal health: the truth is out there

The human vagina is a dynamic ecosystem in which homeostasis depends on mutually beneficial interactions between the host and their microorganisms. However, the vaginal ecosystem can be thrown off balance by a wide variety of factors. Bacterial vaginosis (BV) is the most common vaginal infection in women of childbearing age but its etiology is not yet fully understood, with different controversial theories being raised over the years. What is generally accepted is that BV is often characterized by a shift in the composition of the normal vaginal microbiota, from a Lactobacillus species dominated microbiota to a mixture of anaerobic and facultative anaerobic bacteria. During BV, a polymicrobial biofilm develops in the vaginal microenvironment, being mainly composed of Gardnerella species. The interactions between vaginal microorganisms are thought to play a pivotal role in the shift from health to disease and might also increase the risk of sexually transmitted infections acquisition. Here, we review the current knowledge regarding the specific interactions that occur in the vaginal niche and discuss mechanisms by which these interactions might be mediated. Furthermore, we discuss the importance of novel strategies to fight chronic vaginal infections.

Septic shock caused by Gardnerella vaginalis and Atopobium vaginae

Although bacterial vaginosis is the most common and benign vaginal infection worldwide, some cases of severe acute infections have been described in the literature. We report the case of a 57-year-old French female who developed a life-threatening postoperative peritonitis after a total hysterectomy with adnexectomy in the context of the removal of leiomyosarcoma. The microbiological analysis of the peritoneal fluid identified Gardnerella vaginalis and Atobopium vaginae. The final diagnosis was a septic shock induced by an early onset peritonitis caused by Gardnerella vaginalis and Atobopium vaginae. The normal flora of the genital area could lead to a serious life threatening postoperative infection and should always be in the differential diagnosis.

Gardnerella vaginalis as a Cause of Bacterial Vaginosis: Appraisal of the Evidence From in vivo Models

Koch's postulates dictate the use of experimental models to illustrate features of human disease and provide evidence for a singular organism as the cause. The underlying cause(s) of bacterial vaginosis (BV) has been debated in the literature for over half a century. In 1955, it was first reported that a bacterium now known as Gardnerella vaginalis may be the cause of a condition (BV) resulting in higher vaginal pH, thin discharge, a fishy odor, and the presence of epithelial cells covered in bacteria. Here we review contemporary and historical studies on BV with a focus on reports of experimental infections in human or animal models using Gardnerella vaginalis. We evaluate experimental evidence for the hypothesis that G. vaginalis is sufficient to trigger clinical features of BV or relevant health complications associated with the condition. Additionally, we evaluate in vivo models of co-infection employing G. vaginalis together with other bacterial species to investigate evidence for the hypothesis that G. vaginalis may encourage colonization or virulence of other potential pathogens. Together, these studies paint a complex picture in which G. vaginalis has both direct and indirect roles in the features, health complications, and co-infections associated with BV. We briefly review the current taxonomic landscape and genetic diversity pertinent to Gardnerella and note the limitations of sequence-based studies using different marker genes and priming sites. Although much more study is needed to refine our understanding of how BV develops and persists within the human host, applications of the experimental aspects of Koch's postulates have provided an important glimpse into some of the causal relationships that may govern this condition in vivo.

A Rare Cause of a Scrotal Abscess due to the Symbiotic Infection of Gardnerella vaginalis and Prevotella bivia in an Adult Male

Gardnerella vaginalis (G. vaginalis) is the major bacteria detected in women with bacterial vaginosis (BV). Prevotella bivia (P. bivia) has been demonstrated to show a symbiotic relationship with G. vaginalis. Some men have been shown to be colonized with G. vaginalis in their urogenital or anorectal tracts, however genitourinary infections in males, including balanitis and urethritis, due to this organism appear to be much less common. In this report, we summarize previous cases of men with G. vaginalis infection, and we present a rare and unusual case of a unilateral scrotal abscess caused by G. vaginalis in co-infection with P. bivia.

Gram-Positive Uropathogens, Polymicrobial Urinary Tract Infection, and the Emerging Microbiota of the Urinary Tract

Gram-positive bacteria are a common cause of urinary-tract infection (UTI), particularly among individuals who are elderly, pregnant, or who have other risk factors for UTI. Here we review the epidemiology, virulence mechanisms, and host response to the most frequently isolated Gram-positive uropathogens: Staphylococcus saprophyticus, Enterococcus faecalis, and Streptococcus agalactiae. We also review several emerging, rare, misclassified, and otherwise underreported Gram-positive pathogens of the urinary tract including Aerococcus, Corynebacterium, Actinobaculum, and Gardnerella. The literature strongly suggests that urologic diseases involving Gram-positive bacteria may be easily overlooked due to limited culture-based assays typically utilized for urine in hospital microbiology laboratories. Some UTIs are polymicrobial in nature, often involving one or more Gram-positive bacteria. We herein review the risk factors and recent evidence for mechanisms of bacterial synergy in experimental models of polymicrobial UTI. Recent experimental data has demonstrated that, despite being cleared quickly from the bladder, some Gram-positive bacteria can impact pathogenic outcomes of co-infecting organisms. When taken together, the available evidence argues that Gram-positive bacteria are important uropathogens in their own right, but that some can be easily overlooked because they are missed by routine diagnostic methods. Finally, a growing body of evidence demonstrates that a surprising variety of fastidious Gram-positive bacteria may either reside in or be regularly exposed to the urinary tract and further suggests that their presence is widespread among women, as well as men. Experimental studies in this area are needed; however, there is a growing appreciation that the composition of bacteria found in the bladder could be a potentially important determinant in urologic disease, including susceptibility to UTI.

Transient microbiota exposures activate dormant Escherichia coli infection in the bladder and drive severe outcomes of recurrent disease

Pathogens often inhabit the body asymptomatically, emerging to cause disease in response to unknown triggers. In the bladder, latent intracellular Escherichia coli reservoirs are regarded as likely origins of recurrent urinary tract infection (rUTI), a problem affecting millions of women worldwide. However, clinically plausible triggers that activate these reservoirs are unknown. Clinical studies suggest that the composition of a woman’s vaginal microbiota influences her susceptibility to rUTI, but the mechanisms behind these associations are unclear. Several lines of evidence suggest that the urinary tract is routinely exposed to vaginal bacteria, including Gardnerella vaginalis, a dominant member of the vaginal microbiota in some women. Using a mouse model, we show that bladder exposure to G. vaginalis triggers E. coli egress from latent bladder reservoirs and enhances the potential for life-threatening outcomes of the resulting E. coli rUTI. Transient G. vaginalis exposures were sufficient to cause bladder epithelial apoptosis and exfoliation and interleukin-1-receptor-mediated kidney injury, which persisted after G. vaginalis clearance from the urinary tract. These results support a broader view of UTI pathogenesis in which disease can be driven by short-lived but powerful urinary tract exposures to vaginal bacteria that are themselves not “uropathogenic” in the classic sense. This “covert pathogenesis” paradigm may apply to other latent infections, (e.g., tuberculosis), or for diseases currently defined as noninfectious because routine culture fails to detect microbes of recognized significance.

Millions of women suffer from recurrent urinary tract infections (rUTI) and the only treatment option is prophylactic antibiotics, which contributes to antibiotic resistance. In experimental models, Escherichia coli, the dominant UTI pathogen, establishes reservoirs inside the bladder lining; it is believed that some cases of rUTI in women may be due to these reservoirs awakening in response to triggers that are still unknown. Here we present a new mouse model that demonstrates the first clinically plausible trigger of rUTI arising from these reservoirs. Specifically, we show that bladder exposure to Gardnerella vaginalis, a common member of the vaginal microbial community, can drive the emergence of E. coli from bladder reservoirs. Furthermore, upon its exposure to the urinary tract, this vaginal organism caused severe kidney damage and other complications, suggesting that carriage of particular vaginal bacteria could also impact a woman’s risk for kidney infection. Bladder exposure to G. vaginalis is likely to occur during sexual activity in many women. Taken together, these data provide the first explanation for why certain characteristics of the vaginal microbiota have been linked with rUTI. Finally, our findings suggest that targeting specific members of the vaginal community may be an effective strategy for treating rUTI.

Gardnerella vaginalis bacteremia in a previously healthy man: case report and characterization of the isolate

Gardnerella vaginalis in women causes vaginitis or infections in other sites, such as the urinary tract, but is an infrequent cause of bacteremia. Bacteremia in men is very rare and is typically associated with immunocompromised states. Here we describe G. vaginalis bacteremia in a previously healthy man with renal calculi and urosepsis.