Prevalence of toxic shock syndrome toxin 1-producing Staphylococcus aureus and the presence of antibodies to this superantigen in menstruating women

Toxin exposure and HLA alleles determine serum antibody binding to toxic shock syndrome toxin 1 (TSST-1) of Staphylococcus aureus

Life-threatening toxic shock syndrome is often caused by the superantigen toxic shock syndrome toxin-1 (TSST-1) produced by Staphylococcus aureus. A well-known risk factor is the lack of neutralizing antibodies. To identify determinants of the anti-TSST-1 antibody response, we examined 976 participants of the German population-based epidemiological Study of Health in Pomerania (SHIP-TREND-0). We measured anti-TSST-1 antibody levels, analyzed the colonization with TSST-1-encoding S. aureus strains, and performed a genome-wide association analysis of genetic risk factors. TSST-1-specific serum IgG levels varied over a range of 4.2 logs and were elevated by a factor of 12.3 upon nasal colonization with TSST-1-encoding S. aureus. Moreover, the anti-TSST-1 antibody levels were strongly associated with HLA class II gene loci. HLA-DRB1*03:01 and HLA-DQB1*02:01 were positively, and HLA-DRB1*01:01 as well as HLA-DQB1*05:01 negatively associated with the anti-TSST-1 antibody levels. Thus, both toxin exposure and HLA alleles affect the human antibody response to TSST-1.

Development of in vitro methods to model the impact of vaginal lactobacilli on Staphylococcus aureus biofilm formation on menstrual cups as well as validation of recommended cleaning directions

Introduction

Menstrual cups (MC) are a reusable feminine hygiene product. A recent publication suggested that Staphylococcus aureus (S. aureus) biofilms can form on MCs which may lead to increased risk of menstrual Toxic Shock Syndrome (mTSS). Additionally, there is concern that buildup of residual menses may contribute to microbial growth and biofilm formation further increasing mTSS risk. Quantitative and qualitative analysis of in vitro tests were utilized to determine if S. aureus biofilm could form on MC in the presence of the keystone species Lactobacillus after 12 h of incubation. The methodology was based on a modification of an anaerobic in vitro method that harnesses the keystone species hypothesis by including a representative of vaginal lactic acid bacteria.

Methods

MCs were incubated anaerobically for 12 h in Vaginal Defined Media (VDM) with the two morphologically distinct bacteria, Lactobacillus gasseri (L. gasseri) and S. aureus. Colony Forming Units (CFU) for each organism from the VDM broth and sonicated MC were estimated. In addition, a separate experiment was conducted where S. aureus was grown for 12 h in the absence of L. gasseri. Qualitative analysis for biofilm formation utilized micro-CT (µ-CT) and cryogenic scanning electron microscopy (Cryo-SEM).

Results

Samples collected from the media control had expected growth of both organisms after 12 h of incubation. Samples collected from VDM broth were similar to media control at the end of the 12-h study. Total S. aureus cell density on MC following sonication/rinsing was minimal. Results when using a monoculture of S. aureus demonstrated that there was a significant growth of the organism in the media control and broth as well as the sonicated cups indicating that the presence of L. gasseri was important for controlling growth and adherence of S. aureus. Few rod-shaped bacteria (L. gasseri) and cocci (S. aureus) could be identified on the MCs when grown in a dual species culture inoculum and no biofilm was noted via µ-CT and cryo-SEM. Additionally, efforts to model and understand the validity of the current labeled recommendations for MC cleaning in-between uses are supported.

Discussion

The data support continued safe use of the Tampax® cup when used and maintained as recommended.

The safety assessment of tampons: illustration of a comprehensive approach for four different products

Introduction

We illustrate a comprehensive tampon safety assessment approach that assures products can be used safely. Material biocompatibility, vaginal mucosa assessment, vaginal microbiome evaluation, and in vitro assessment of potential risk of staphylococcal toxic shock syndrome expressed through growth of Staphylococcus aureus (S. aureus) and production of TSST-1 are the four essential portions of the approach. Post-marketing surveillance informs of possible health effects that warrant follow up. The approach meets or exceeds US and international regulatory guidance and is described through the example of four tampon products.

Methods/Results

Each product is comprised mostly of large molecular weight components (cotton, rayon, polymers) that cannot pass the vaginal mucosa, are widely used across the industry, and replete with a vast body of safety data and a long history of safe use in the category. Quantitative risk assessment of all small molecular weight components assured a sufficient margin of safety supporting their use. Vaginal mucosa assessment confirmed that pressure points, rough edges and/or sharp contact points were absent. A randomized cross-over clinical trial (ClinicalTrials.gov Identifier: NCT03478371) revealed favorable comfort ratings, and few complaints of irritation, burning, stinging, or discomfort upon insertion, wear, and removal. Adverse events were few, mild in severity, self-limited and resolved without treatment. Vaginal microbiota assessment in vitro presented no adverse effect on microbial growth. Culture-independent microbiome analyses from vaginal swab samples obtained during the clinical trial showed no differences attributable to tampon usage, but instead due to statistically significant subject-to-subject variability. Growth of S. aureus and TSST-1 toxin production in the presence of any of the four products in vitro were statistically significantly reduced when compared to medium control alone.

Discussion

The data from the four elements of the comprehensive safety assessment approach illustrated herein confirm that tampons evaluated using this system can be used safely for menstrual protection. A post-marketing surveillance system that monitors and responds to in-market experiences indicated in-use tolerability of the product among consumers, thus confirming the conclusions of the pre-marketing safety assessment.

Staphylococcal Enterotoxin B and C Mutants and Vaccine Toxoids

Three mutants individually of both staphylococcal enterotoxins B and C were prepared by site-specific mutagenesis of enterotoxin amino acids that contact host T lymphocyte immune cell receptor sites (N23A, Q210A, and N23A/Q210A); these amino acids are shared between the two enterotoxins, and mutations reduce the interaction with the variable part of the β-chain of the T lymphocyte receptor. The mutant proteins, as expressed in Staphylococcus aureus RN4220, lacked biological toxicity as measured by the loss of (i) stimulation of rabbit splenocyte proliferation, (ii) pyrogenicity, and (iii) the ability to enhance the lethality of endotoxin shock, compared to wild-type enterotoxins. In addition, the mutants were able to vaccinate rabbits against pyrogenicity, the enhancement of endotoxin shock, and lethality in a pneumonia model when animals were challenged with methicillin-resistant S. aureus. Three vaccine injections (one primary and two boosters) protected rabbits for at least 3.5 months postvaccination when challenged with wild-type enterotoxins (last time point tested). These mutant proteins have the potential to function as toxoid vaccines against these two causes of nonmenstrual toxic shock syndrome (TSS). IMPORTANCE Toxic shock syndrome toxin 1 (TSST-1) and staphylococcal enterotoxins B and C cause the majority of cases of staphylococcal toxic shock syndrome. Previously, vaccine toxoids of TSST-1 have been prepared. In this study, vaccine toxoids of enterotoxins B and C were prepared. The toxoids lost biological toxicity but were able to vaccinate rabbits against lethal TSS.

Targeted Proteomics Analysis of Staphylococcal Superantigenic Toxins in Menstrual Fluid from Women with Menstrual Toxic Shock Syndrome (mTSS)

Menstrual toxic shock syndrome (mTSS) is a rare life-threatening febrile illness that occurs in women using intravaginal menstrual protection. It is caused by toxic shock syndrome toxin 1 (TSST-1) produced by Staphylococcus aureus, triggering a sudden onset of rash and hypotension, subsequently leading to multiple organ failure. Detecting TSST-1 and S. aureus virulence factors in menstrual fluid could accelerate the diagnosis and improve therapeutic management of mTSS. However, menstrual fluid is a highly complex matrix, making detection of bacterial toxins challenging. Here, we present a mass-spectrometry-based proteomics workflow for the targeted, quantitative analysis of four S. aureus superantigenic toxins in menstrual fluids (TSST-1, SEA, SEC, and SED). This method was applied to characterize toxin levels in menstrual fluids collected from patients with mTSS and healthy women. Toxins were detectable in samples from patients with mTSS and one healthy donor at concentrations ranging from 0 to 0.46 µg/mL for TSST-1, and 0 to 1.07 µg/mL for SEC. SEA and SED were never detected in clinical specimens, even though many S. aureus strains were positive for the corresponding genes. The method presented here could be used to explore toxin production in vivo in users of intravaginal devices to improve the diagnosis, understanding, and prevention of mTSS.

Non-thermal Plasma Treatment of ESKAPE Pathogens: A Review

The acronym ESKAPE refers to a group of bacteria consisting of Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp. They are important in human medicine as pathogens that show increasing resistance to commonly used antibiotics; thus, the search for new effective bactericidal agents is still topical. One of the possible alternatives is the use of non-thermal plasma (NTP), a partially ionized gas with the energy stored particularly in the free electrons, which has antimicrobial and anti-biofilm effects. Its mechanism of action includes the formation of pores in the bacterial membranes; therefore, resistance toward it is not developed. This paper focuses on the current overview of literature describing the use of NTP as a new promising tool against ESKAPE bacteria, both in planktonic and biofilm forms. Thus, it points to the fact that NTP treatment can be used for the decontamination of different types of liquids, medical materials, and devices or even surfaces used in various industries. In summary, the use of diverse experimental setups leads to very different efficiencies in inactivation. However, Gram-positive bacteria appear less susceptible compared to Gram-negative ones, in general.

TSST-1+Staphylococcus aureus in Bullous Pemphigoid

A potential role of Staphylococcus aureus in bullous pemphigoid was explored by examining the colonization rate in patients with new-onset disease compared with that in age- and sex-matched controls. S. aureus colonization was observed in 85% of bullous pemphigoid lesions, 3-6-fold higher than the nares or unaffected skin from the same patients (P ≤ 0.003) and 6-fold higher than the nares or skin of controls (P ≤ 0.0015). Furthermore, 96% of the lesional isolates produced the toxic shock syndrome toxin-1 superantigen, and most of these additionally exhibited homogeneous expression of the enterotoxin gene cluster toxins. Toxic shock syndrome toxin-1‒neutralizing antibodies were not protective against colonization. However, S. aureus colonization was not observed in patients who had recently received antibiotics, and the addition of antibiotics with staphylococcal coverage eliminated S. aureus and resulted in clinical improvement. This study shows that toxic shock syndrome toxin-1‒positive S. aureus is prevalent in bullous pemphigoid lesions and suggests that early implementation of antibiotics may be of benefit. Furthermore, our results suggest that S. aureus colonization could provide a source of infection in patients with bullous pemphigoid, particularly in the setting of high-dose immunosuppression.

Surgical Infection Society 2020 Updated Guidelines on the Management of Complicated Skin and Soft Tissue Infections

Background: The Surgical Infection Society (SIS) Guidelines for the treatment of complicated skin and soft tissue infections (SSTIs) were published in October 2009 in Surgical Infections. The purpose of this project was to provide a succinct update on the earlier guidelines based on an additional decade of data. Methods: We reviewed the previous guidelines eliminating bite wounds and diabetic foot infections including their associated references. Relevant articles on the topic of complicated SSTIs from 2008-2020 were reviewed and graded individually. Comparisons were then made between the old and the new graded recommendations with review of the older references by two authors when there was disparity between the grades. Results: The majority of new studies addressed antimicrobial options and duration of therapy particularly in complicated abscesses. There were fewer updated studies on diagnosis and specific operative interventions. Many of the topics addressed in the original guidelines had no new literature to evaluate. Conclusions: Most recommendations remain unchanged from the original guidelines with the exception of increased support for adjuvant antimicrobial therapy after drainage of complex abscess and increased data for the use of alternative antimicrobial agents.

Immune-Based Anti-Staphylococcal Therapeutic Approaches

Widespread methicillin-resistant Staphylococcus aureus (S. aureus) infections within community and healthcare settings are responsible for accelerated development of antibiotic resistance. As the antibiotic pipeline began drying up, alternative strategies were sought for future treatment of S. aureus infections. Here, we review immune-based anti-staphylococcal strategies that, unlike conventional antibiotics, target non-essential gene products elaborated by the pathogen. These strategies stimulate narrow or broad host immune mechanisms that are critical for anti-staphylococcal defenses. Alternative approaches aim to disrupt bacterial virulence mechanisms that enhance pathogen survival or induce immunopathology. Although immune-based therapeutics are unlikely to replace antibiotics in patient treatment in the near term, they have the potential to significantly improve upon the performance of antibiotics for treatment of invasive staphylococcal diseases.

High Titer Persistent Neutralizing Antibodies Induced by TSST-1 Variant Vaccine Against Toxic Shock Cytokine Storm

Staphylococcal superantigen toxins lead to a devastating cytokine storm resulting in shock and multi-organ failure. We have previously assessed the safety and immunogenicity of a recombinant toxic shock syndrome toxin 1 variant vaccine (rTSST-1v) in clinical trials (NCT02971670 and NCT02340338). The current study assessed neutralizing antibody titers after repeated vaccination with escalating doses of rTSST-1v. At study entry, 23 out of 34 subjects (67.6%) had neutralizing antibody titers inhibiting T cell activation as determined by ³H-thymidine incorporation at a serum dilution of ≤1:100 with similar figures for inhibition of IL-2 activation (19 of 34 subjects, 55.9%) as assessed by quantitative PCR. After the first vaccination, numbers of subjects with neutralization titers inhibiting T cell activation (61.7% ≥ 1:1000) and inhibiting IL-2 gene induction (88.2% ≥ 1:1000) increased. The immune response was augmented after the second vaccination (inhibiting T cell activation: 78.8% ≥ 1:1000; inhibiting IL-2 induction: 93.9% ≥ 1:1000) corroborated with a third immunization months later in a small subgroup of subjects. Assessment of IFNγ, TNFα and IL-6 inhibition revealed similar results, whereas neutralization titers did not change in placebo participants. Antibody titer studies show that vaccination with rTSST-1v in subjects with no/low neutralizing antibodies can rapidly induce high titer neutralizing antibodies persisting over months.

Kawasaki syndrome: role of superantigens revisited

Kawasaki syndrome (KS) is an acute vasculitis in children complicated by the development of heart disease. Despite its description over 50 years ago, the etiology of coronary artery disease in KS is unknown. High dose intravenous immunoglobulin is the most effective approach to reduce cardiovascular complications. It remains unclear why patients with KS develop coronary artery aneurysms. A subset of patients is resistant to immunoglobulin therapy. Given the heterogeneity of clinical features, variability of history, and therapeutic response, KS may be a cluster of phenotypes triggered by multiple infectious agents and influenced by various environmental, genetic, and immunologic responses. The cause of KS is unknown, and a diagnostic test remains lacking. A better understanding of mechanisms leading to acute KS would contribute to a more precision medicine approach for this complex disease. In the current viewpoint, we make the case for microbial superantigens as important causes of KS.

Device-Associated Menstrual Toxic Shock Syndrome

In the 1980s, menstrual toxic shock syndrome (mTSS) became a household topic, particularly among mothers and their daughters. The research performed at the time, and for the first time, exposed the American public as well as the biomedical community, in a major way, to understanding disease progression and investigation. Those studies led to the identification of the cause, Staphylococcus aureus and the pyrogenic toxin superantigen TSS toxin 1 (TSST-1), and many of the risk factors, for example, tampon use. Those studies in turn led to TSS warning labels on the outside and inside of tampon boxes and, as important, uniform standards worldwide of tampon absorbency labeling. This review addresses our understanding of the development and conclusions related to mTSS and risk factors. We leave the final message that even though mTSS is not commonly in the news today, cases continue to occur. Additionally, S. aureus strains cycle in human populations in roughly 10-year intervals, possibly dependent on immune status. TSST-1-producing S. aureus bacteria appear to be reemerging, suggesting that physician awareness of this emergence and mTSS history should be heightened.

Association of characteristics of tampon use with menstrual toxic shock syndrome in France

BACKGROUND

Menstrual tampons are widely used in western countries. Indirect evidence suggests that tampon misuse could be associated with an increased risk of menstrual toxic shock syndrome (MTSS). The aim of this study was to determine what characteristics of tampon use are associated with increased risk of menstrual toxic shock syndrome (MTSS).

METHODS

A nationwide, case-control study in France, was conducted with women that use tampons with MTSS diagnoses according to the CDC diagnostic criteria (n = 55, from January 2011, to December 2017) and a control group of women with no MTSS history (n = 126, from February to December 2017). Information regarding tampon use during a 6-month period was collected. Associations between tampon use and MTSS were assessed using logistic regression models stratified by residential area.

FINDINGS

Compared to controls, women diagnosed with MTSS more frequently reported maximum tampon wear of >6 h (62% vs. 41%; P = 0.02), overnight tampon use (77% vs. 54%; P = 0.006), and neither read nor followed tampon instructions in case of reading (65% vs. 42%; P = 0.006). In univariate analysis, MTSS risk was two-fold higher with tampon use for >6 consecutive hours (odds ratio, 2.3 [95% CI, 1.2-4.5]), and three-fold higher with tampon use during sleep for >8 h (odds ratio, 3.2 [95% CI, 1.4-7.7]). In multivariate logistic regression analysis, only maximum tampon use for >6 h (odds ratio, 2.03 [95% CI, 1.04-3.98]), and neither read nor followed the tampon instructions in case of reading (odds ratio, 2.25 [95% CI, 1.15-4.39]) were independently associated with MTSS.

INTERPRETATION

Our study suggests that the risk of MTSS was associated with using tampons for more than 6 h, overnight tampon use during sleep, and neither read nor followed tampon insertion instructions in case of reading.

FUNDING

LABEX ECOFECT (ANR-11-LABX-0048) of Université de Lyon within the programme "Investissements d'Avenir" (ANR-11-IDEX-0007) operated by the French National Research Agency (ANR).

Toxic Shock Syndrome: Still a Timely Diagnosis

BACKGROUND

Toxic shock syndrome (TSS) is an acute, severe, toxin-mediated disease, characterized by fever, hypotension, and multiorgan system involvement. Toxic shock syndrome has made headlines because of its high associated morbidity and mortality rate in previously healthy young females. Incidence peaked in the early 1980s owing to increased usage of ultra-absorbent tampons. After improved patient education and tampon labeling, the incidence of menstrual TSS has declined.

CASE

A previously healthy 14-year-old girl presented to an urgent care center with a 2-day history of fever, erythematous maculopapular rash, vomiting, diarrhea, and malaise. She was found to be tachycardic and hypotensive. Investigations revealed thrombocytopenia, an elevated white count and lactate, and acute kidney injury, consistent with septic shock. Recent tampon usage with menstruation was reported, and a pelvic examination revealed purulent vaginal discharge. The patient was transferred to a pediatric intensive care unit for antibiotic and vasopressor therapy. Vaginal swabs later tested positive for Staphylococcus aureus and TSS toxin-1.

CONCLUSIONS

Although the incidence of TSS has decreased in recent years, it is crucial that clinicians rapidly recognize and treat this life-threatening condition. Emergency physicians should always have a high index of suspicion for TSS in young females presenting without another obvious cause of shock. A pelvic examination should always be completed in these cases.

Virulence factors and antimicrobial resistance of Staphylococcus aureus isolated from the production process of Minas artisanal cheese from the region of Campo das Vertentes, Brazil

Staphylococcus aureus is one of the main pathogens found in cheeses produced with raw milk, including Minas artisanal cheese from Brazil. However, information about S. aureus isolated from artisanal cheeses and its sources of production in small-scale dairies is very limited. We aimed to characterize the virulence factors of S. aureus isolated from raw milk, endogenous starter culture, Minas artisanal cheese, and cheese handlers from the region of Campo das Vertentes, Minas Gerais, Brazil. We identified the staphylococcal isolates by MALDI-TOF mass spectrometry. We evaluated biofilm production on Congo red agar and polystyrene plates. We used PCR to detect icaA, icaB, icaC, sea, seb, sec, sed, see, tsst-1, agr, and mecA. We evaluated the expression of staphylococcal toxin genes in PCR-positive staphylococcal isolates using quantitative reverse-transcription PCR, and we evaluated the production of these toxins and their hemolytic activity in vitro. We also evaluated the antimicrobial resistance profile of the staphylococcal isolates. For statistical analysis, we used cluster analysis, χ² tests, and correspondence tests. We analyzed 76 staphylococcal isolates. According to PCR, 18.42, 18.42, 2.63, and 77.63% were positive for sea, tsst-1, sec, and agr, respectively. We found low expression of staphylococcal toxin genes according to quantitative reverse-transcription PCR, and only 2 staphylococcal isolates produced toxic shock syndrome toxins. A total of 43 staphylococcal isolates (56.58%) had hemolytic activity; 53 were biofilm-forming on Congo red agar (69.73%), and 62 on polystyrene plates (81.58%). None of the staphylococcal isolates expressed the mecA gene, and none presented a multi-drug resistance pattern. The highest resistance was observed for penicillin G (67.11%) in 51 isolates and for tetracycline (27.63%) in 21 isolates. The staphylococcal isolates we evaluated had toxigenic potential, with a higher prevalence of sea and tsst-1. Biofilm production was the main virulence factor of the studied bacteria. Six clusters were formed whose distribution frequencies differed for hemolytic activity, biofilm formation (qualitative and quantitative analyses), and resistance to penicillin, tetracycline, and erythromycin. These findings emphasize the need for effective measures to prevent staphylococcal food poisoning by limiting S. aureus growth and enterotoxin formation throughout the food production chain and the final product.

Menstrual toxic shock syndrome: case report and systematic review of the literature

Menstrual toxic shock syndrome (mTSS) is a life-threatening disease caused by superantigen-producing Staphylococcus aureus. Incidence ranges from 0·03 to 0·50 cases per 100 000 people, with overall mortality around 8%. In this Grand Round, we present the case of a previously healthy 23-year-old menstruating woman who was diagnosed with mTSS after she presented at our hospital with a septic condition for the second time. The diagnosis was confirmed by fulfilment of the clinical criteria outlined by the US Centers for Disease Control and Prevention (CDC; fever, rash, desquamation, hypotension, and multi-system involvement) as well as a nasal swab positive for the S aureus strain and presence of the gene encoding for toxic shock syndrome toxin 1 (TSST-1). In the early 1980s, when mTSS was first described, use of tampons was considered the main risk factor. Today, the complex interplay between pathogenic factors of S aureus, immunological mechanisms of the host, and changes in the vaginal ecosystem during menstruation has broadened current understanding of the disease, and the CDC criteria have appreciable limitations in everyday clinical practice.

TBA225, a fusion toxoid vaccine for protection and broad neutralization of staphylococcal superantigens

Superantigens (SAgs) play a major role in the pathogenesis of Staphylococcus aureus and are associated with several diseases, including food poisoning, bacterial arthritis, and toxic shock syndrome. Monoclonal antibodies to these SAgs, primarily TSST-1, SEB and SEA have been shown to provide protection in animal studies and to reduce clinical severity in bacteremic patients. Here we quantify the pre-existing antibodies against SAgs in many human plasma and IVIG samples and demonstrate that in a major portion of the population these antibody titers are suboptimal and IVIG therapy only incrementally elevates the anti-SAg titers. Our in vitro neutralization studies show that a combination of antibodies against SEA, SEB,and TSST-1 can provide broad neutralization of staphylococcal SAgs. We report a single fusion protein (TBA₂₂₅) consisting of the toxoid versions of TSST-1, SEB and SEA and demonstrate its immunogenicity and protective efficacy in a mouse model of toxic shock. Antibodies raised against this fusion vaccine provide broad neutralization of purified SAgs and culture supernatants of multiple clinically relevant S. aureus strains. Our data strongly supports the use of this fusion protein as a component of an anti-virulence based multivalent toxoid vaccine against S. aureus disease.

The effect of vaginal microbial communities on colonization by Staphylococcus aureus with the gene for toxic shock syndrome toxin 1 (TSST-1): a case-control study

Menstrual toxic shock syndrome is associated with vaginal colonization by Staphylococcus aureus strains that encode toxic shock syndrome toxin 1 (tst+). Interestingly, a small proportion of women are colonized by S. aureus tst+ but do not have symptoms of toxic shock syndrome. Here we sought to determine if differences in the species composition of vaginal bacterial communities reflect a differential risk of colonization by S. aureus capable of producing toxic shock syndrome toxin 1 (TSST-1). The composition of vaginal communities of women that were or were not colonized with S. aureus tst+ were compared based on terminal restriction fragment length polymorphism (T-RFLP) profiles and sequences of cloned 16S rRNA genes. There were no detectable differences in community composition or species rank abundance between communities of women vaginally colonized with S. aureus tst+ as compared to those that were not. Phylogenetic analysis of cloned 16S rRNA gene sequences showed that the predominant members of communities of women colonized with S. aureus tst+ were indistinguishable from those of other healthy women. The data suggest that the numerically dominant members of vaginal communities do not preclude colonization and proliferation of S. aureus tst+ within indigenous microbial communities of the vagina.

Fulminant Staphylococcal Infections

Fulminant staphylococcal infection indicates an explosive, intense, and severe infection occurring in a patient whose previous condition and antecedent would never have caused any anticipation of life-threatening development. This includes necrotizing pneumonia, necrotizing fasciitis, and to some extent toxic shock syndrome and infective endocarditis. In the three former diseases, toxin production plays a major role whereas in the latter (fulminant presentation of infective endocarditis), association with any particular toxinic profile has never been demonstrated. This article reviews the clinical, pathophysiological, and therapeutic aspects of these diseases.

Complex ecological interactions of Staphylococcus aureus in tampons during menstruation

Menstrual toxic shock syndrome (mTSS) is a severe disease that occurs in healthy women vaginally colonized by Staphylococcus aureus producing toxic shock toxin 1 and who use tampons. The aim of the present study was to determine the impact of the composition of vaginal microbial communities on tampon colonisation by S. aureus during menses. We analysed the microbiota in menstrual fluids extracted from tampons from 108 healthy women and 7 mTSS cases. Using culture, S. aureus was detected in menstrual fluids of 40% of healthy volunteers and 100% of mTSS patients. Between class analysis of culturomic and 16S rRNA gene metabarcoding data indicated that the composition of the tampons' microbiota differs according to the presence or absence of S. aureus and identify discriminating genera. However, the bacterial communities of tampon fluid positive for S. aureus did not cluster together. No difference in tampon microbiome richness, diversity, and ecological distance was observed between tampon vaginal fluids with or without S. aureus, and between healthy donors carrying S. aureus and mTSS patients. Our results show that the vagina is a major niche of. S. aureus in tampon users and the composition of the tampon microbiota control its virulence though more complex interactions than simple inhibition by lactic acid-producing bacterial species.

Innate immune responses following Kawasaki disease and toxic shock syndrome

The pathogenesis of Kawasaki disease (KD) remains unknown and there is accumulating evidence for the importance of the innate immune system in initiating and mediating the host inflammatory response. We compared innate immune responses in KD and toxic shock syndrome (TSS) participants more than two years after their acute illness with control participants to investigate differences in their immune phenotype. Toxic shock syndrome shares many clinical features with KD; by including both disease groups we endeavoured to explore changes in innate immune responses following acute inflammatory illnesses more broadly. We measured the in vitro production of interferon (IFN)-γ, tumour necrosis factor (TNF)-α, interleukin (IL)-1β, IL-6, IL-1 receptor antagonist (IL-1ra), and IL-10 following whole blood stimulation with toll-like receptor and inflammasome ligands in 52 KD, 20 TSS, and 53 control participants in a case-control study. Analyses were adjusted for age, sex, and unstimulated cytokine concentrations. Compared to controls, KD participants have reduced IL-1ra production in response to stimulation with double stranded RNA (geometric mean ratio (GMR) 0.37, 95% CI 0.15, 0.89, p = 0.03) and increased IL-6 production in response to incubation with Lyovec™ (GMR 5.48, 95% CI 1.77, 16.98, p = 0.004). Compared to controls, TSS participants have increased IFN-γ production in response to peptidoglycan (GMR 4.07, 95% CI 1.82, 9.11, p = 0.001), increased IL-1β production to lipopolysaccharide (GMR 1.64, 95% CI 1.13, 2.38, p = 0.01) and peptidoglycan (GMR 1.61, 95% CI 1.11, 2.33, p = 0.01), and increased IL-6 production to peptidoglycan (GMR 1.45, 95% CI 1.10, 1.92, p = 0.01). Years following the acute illness, individuals with previous KD or TSS exhibit a pro-inflammatory innate immune phenotype suggesting a possible underlying immunological susceptibility or innate immune memory.

The Evaluation and Management of Toxic Shock Syndrome in the Emergency Department: A Review of the Literature

BACKGROUND

Toxic shock syndrome (TSS) is a severe, toxin-mediated illness that can mimic several other diseases and is lethal if not recognized and treated appropriately.

OBJECTIVE

This review provides an emergency medicine evidence-based summary of the current evaluation and treatment of TSS.

DISCUSSION

The most common etiologic agents are Staphylococcus aureus and Streptococcus pyogenes. Sources of TSS include postsurgical wounds, postpartum, postabortion, burns, soft tissue injuries, pharyngitis, and focal infections. Symptoms are due to toxin production and infection focus. Early symptoms include fever, chills, malaise, rash, vomiting, diarrhea, and hypotension. Diffuse erythema and desquamation may occur later in the disease course. Laboratory assessment may demonstrate anemia, thrombocytopenia, elevated liver enzymes, and abnormal coagulation studies. Diagnostic criteria are available to facilitate the diagnosis, but they should not be relied on for definitive diagnosis. Rather, specific situations should trigger consideration of this disease process. Treatment involves intravenous fluids, source control, and antibiotics. Antibiotics should include a penicillinase-resistant penicillin, cephalosporin, or vancomycin (in methicillin-resistant S. aureus prevalent areas) along with either clindamycin or linezolid.

CONCLUSION

TSS is a potentially deadly disease requiring prompt recognition and treatment. Focused history, physical examination, and laboratory testing are important for the diagnosis and management of this disease. Understanding the evaluation and treatment of TSS can assist providers with effectively managing these patients.

[Staphylococcal toxic shock syndrome at a chronic hemodialysis]

Le syndrome de choc toxique staphylococcique est un syndrome infectieux aigu et systémique lié à l'activité super-antigénique des toxines staphylococciques. C'est une pathologie qui est assez rare mais reste grevée d'une mortalité considérable malgré la prise en charge thérapeutique. La porte d'entrée est le plus souvent cutanée avec dissémination bactériémique secondaire pourrait être sujet de mesures préventives. Nous rapportons le cas d'un choc toxique à staphylocoque doré d'évolution rapidement mortelle, développé chez un hémodialysé chronique dont la porte d'entrée à partir de la fistule artério-veineuse était soupçonnée.

Examining the safety of menstrual cups among rural primary school girls in western Kenya: observational studies nested in a randomised controlled feasibility study

OBJECTIVE

Examine the safety of menstrual cups against sanitary pads and usual practice in Kenyan schoolgirls.

DESIGN

Observational studies nested in a cluster randomised controlled feasibility study.

SETTING

30 primary schools in a health and demographic surveillance system in rural western Kenya.

PARTICIPANTS

Menstruating primary schoolgirls aged 14-16 years participating in a menstrual feasibility study.

INTERVENTIONS

Insertable menstrual cup, monthly sanitary pads or 'usual practice' (controls).

OUTCOME MEASURES

Staphylococcus aureus vaginal colonization, Escherichia coli growth on sampled used cups, toxic shock syndrome or other adverse health outcomes.

RESULTS

Among 604 eligible girls tested, no adverse event or TSS was detected over a median 10.9 months follow-up. S. aureusprevalence was 10.8%, with no significant difference over intervention time or between groups. Of 65 S.aureus positives at first test, 49 girls were retested and 10 (20.4%) remained positive. Of these, two (20%) sample isolates tested positive for toxic shock syndrome toxin-1; both girls were provided pads and were clinically healthy. Seven per cent of cups required replacements for loss, damage, dropping in a latrine or a poor fit. Of 30 used cups processed for E. coli growth, 13 (37.1%, 95% CI 21.1% to 53.1%) had growth. E. coli growth was greatest in newer compared with established users (53%vs22.2%, p=0.12).

CONCLUSIONS

Among this feasibility sample, no evidence emerged to indicate menstrual cups are hazardous or cause health harms among rural Kenyan schoolgirls, but large-scale trials and post-marketing surveillance should continue to evaluate cup safety.

pH-Dependent Antimicrobial Properties of Copper Oxide Nanoparticles in Staphylococcus aureus

The antimicrobial properties of CuO nanoparticles have been investigated, but the underlying mechanisms of toxicity remain the subject of debate. Here, we show that CuO nanoparticles exhibit significant toxicity at pH 5 against four different Staphylococcus aureus (S. aureus) strains, including Newman, SA113, USA300, and ATCC6538. At this pH, but not at pH 6 and 7, 5 mM CuO nanoparticles effectively caused reduction of SA113 and Newman cells and caused at least 2 log reduction, whereas 20 mM killed most strains but not USA300. At 5 mM, the nanoparticles were also found to dramatically decrease reductase activity in SA113, Newman, and ATCC6538 cells, but not USA300 cells. In addition, analysis of X-ray absorption near-edge structure and extended X-ray absorption fine structure confirmed that S. aureus cells exposed to CuO nanoparticles contain CuO, indicating that Cu²⁺ ions released from nanoparticles penetrate bacterial cells and are subsequently oxidized intracellularly to CuO at mildly acidic pH. The CuO nanoparticles were more soluble at pH 5 than at pH 6 and 7. Taken together, the data conclusively show that the toxicity of CuO nanoparticles in mildly acidic pH is caused by Cu²⁺ release, and that USA300 is more resistant to CuO nanoparticles (NPs) than the other three strains.

The Frequency of Staphylococcus aureus Isolated from Endocervix of Infertile Women in Northwest Iran

Background

Infertility is one of the major social issues. Due to the asymptomatic cervical infection associated with Staphylococcus aureus (S. aureus), the majority of patients remain undiagnosed. The present study intended to assess the frequency of S. aureus isolated from infertile women’s endocervix in northwest Iran.

Materials and Methods

In a descriptive cross sectional study, specimens were randomly collected during vagina examination using a sterile speculum and swabbing. After performance of antibiotic susceptibility testing, polymerase chain reaction (PCR) was used to identify methicillin-resistance S. aureus (MRSA) and toxic shock syndrome toxin-1 (TSST-1).

Results

About 26 (26%) and 9 (9%) women’s urogenital tracts were colonized by S. aureus and Candida spp., respectively, of which three (11.5%) patients were infected with fungi and S. aureus, simultaneously. Antibiotic susceptibility results showed high activity of vancomycin and co-trimoxazole on isolates. Regarding PCR results, mecA sequences were detected in 7 (26.9%) strains, whilst the tst gene encoding TSST-1 was not detected in any of clinical strains.

Conclusion

The prevalence of S. aureus was very high in infertile women. Therefore, it demands all patients undergoing infertility treatment to be investigated thoroughly for this type of infection.

A confirmed case of toxic shock syndrome associated with the use of a menstrual cup

Toxic shock syndrome (TSS) is caused by toxic bacteria and has been associated with prolonged, continual use of high-absorbency tampons. This article documents the first case of TSS associated with the use of a menstrual cup in a 37-year-old woman. The authors also discuss the history of TSS associated with tampon use and the mechanisms by which menstrual cups may also lead to the syndrome.

Menstrual cups have been reported to be an acceptable substitute for tampons. These flexible cups have also been reported to provide a sustainable solution to menstrual management, with modest cost savings and no significant health risk.

The present article documents the first case of toxic shock syndrome associated with the use of a menstrual cup in a woman 37 years of age, using a menstrual cup for the first time. Toxic shock syndrome and the literature on menstrual cups is reviewed and a possible mechanism for the development of toxic shock syndrome in the patient is described.

Impact of the Regulators SigB, Rot, SarA and sarS on the Toxic Shock Tst Promoter and TSST-1 Expression in Staphylococcus aureus

Staphylococcus aureus is an important pathogen manifesting virulence through diverse disease forms, ranging from acute skin infections to life-threatening bacteremia or systemic toxic shock syndromes. In the latter case, the prototypical superantigen is TSST-1 (Toxic Shock Syndrome Toxin 1), encoded by tst(H), and carried on a mobile genetic element that is not present in all S. aureus strains. Transcriptional regulation of tst is only partially understood. In this study, we dissected the role of sarA, sarS (sarH1), RNAIII, rot, and the alternative stress sigma factor sigB (σ^B). By examining tst promoter regulation predominantly in the context of its native sequence within the SaPI1 pathogenicity island of strain RN4282, we discovered that σ^B emerged as a particularly important tst regulator. We did not detect a consensus σ^B site within the tst promoter, and thus the effect of σ^B is likely indirect. We found that σ^B strongly repressed the expression of the toxin via at least two distinct regulatory pathways dependent upon sarA and agr. Furthermore rot, a member of SarA family, was shown to repress tst expression when overexpressed, although its deletion had no consistent measurable effect. We could not find any detectable effect of sarS, either by deletion or overexpression, suggesting that this regulator plays a minimal role in TSST-1 expression except when combined with disruption of sarA. Collectively, our results extend our understanding of complex multifactorial regulation of tst, revealing several layers of negative regulation. In addition to environmental stimuli thought to impact TSST-1 production, these findings support a model whereby sporadic mutation in a few key negative regulators can profoundly affect and enhance TSST-1 expression.

Staphylococcal superantigens interact with multiple host receptors to cause serious diseases

Staphylococcus aureus strains that cause human diseases produce a large family of pyrogenic toxin superantigens (SAgs). These include toxic shock syndrome toxin-1 (TSST-1), the staphylococcal enterotoxins (SEs), and the SE-like proteins; to date, 23 staphylococcal SAgs have been described. Among the SAgs, three have been highly associated with human diseases (TSST-1, SEB, and SEC), likely because they are produced in high concentrations compared to other SAgs. Another major family of exotoxins produced by S. aureus is the cytolysins, particularly α-, β-, γ-, and δ-toxins, phenol soluble modulins, and leukocidins. This review discusses the association of SAgs with human diseases and particularly the "outside-in" signaling mechanism that leads to SAg-associated diseases. We discuss SAg interactions with three host immune cell receptors, including variable regions of the β-chain of the T cell receptor, MHC II α- and/or β-chains, and an epithelial/endothelial cell receptor that may include CD40. To a lesser extent, we discuss the role of cytolysins in facilitating disease production by SAgs.

Chronic superantigen exposure induces systemic inflammation, elevated bloodstream endotoxin, and abnormal glucose tolerance in rabbits: possible role in diabetes

Excessive weight and obesity are associated with the development of diabetes mellitus type 2 (DMII) in humans. They also pose high risks of Staphylococcus aureus colonization and overt infections. S. aureus causes a wide range of severe illnesses in both healthy and immunocompromised individuals. Among S. aureus virulence factors, superantigens are essential for pathogenicity. In this study, we show that rabbits that are chronically exposed to S. aureus superantigen toxic shock syndrome toxin-1 (TSST-1) experience impaired glucose tolerance, systemic inflammation, and elevated endotoxin levels in the bloodstream, all of which are common findings in DMII. Additionally, such DMII-associated findings are also seen through effects of TSST-1 on isolated adipocytes. Collectively, our findings suggest that chronic exposure to S. aureus superantigens facilitates the development of DMII, which may lead to therapeutic targeting of S. aureus and its superantigens.

Obesity has a strong correlation with type 2 diabetes, in which fatty tissue, containing adipocytes, contributes to the development of the illness through altered metabolism and chronic inflammation. The human microbiome changes in persons with obesity and type 2 diabetes, including increases in Staphylococcus aureus colonization and overt infections. While the microbiome is essential for human wellness, there is little understanding of the role of microbes in obesity or the development of diabetes. Here, we demonstrate that the S. aureus superantigen toxic shock syndrome toxin-1 (TSST-1), an essential exotoxin in pathogenesis, induces inflammation, lipolysis, and insulin resistance in adipocytes both in vitro and in vivo. Chronic stimulation of rabbits with TSST-1 results in impaired systemic glucose tolerance, the hallmark finding in type 2 diabetes in humans, suggesting a role of S. aureus and its superantigens in the progression to type 2 diabetes.

Prevalence of antibody to toxic shock syndrome toxin-1 in burn patients

Background

Burn wounds lack normal barriers that protect against pathogenic bacteria, and burn patients are easily colonized and infected by Staphylococcus aureus. Toxic shock syndrome (TSS) is a rare but fatal disease caused by S. aureus. A lack of detectable antibodies to TSS toxin-1 (TSST-1) in serum indicates susceptibility to TSS.

Methods

A total of 207 patients (169 men and 38 women; median age, 42.5 yr) admitted to a burn center in Korea were enrolled in this study. The serum antibody titer to TSST-1 was measured by sandwich ELISA. S. aureus isolates from the patients' nasal swab culture were tested for TSST-1 toxin production by PCR-based detection of the TSST-1 toxin gene.

Results

One hundred seventy-four (84.1%) patients showed positive results for antibody against TSST-1. All patients aged ≥61 yr (n=28) and <26 months (n=7) were positive for the anti-TSST-1 antibody. S. aureus was isolated from 70 patients (33.8%), and 58.6% of the isolates were methicillin resistant. Seventeen patients were colonized with TSST-1-producing S. aureus. The antibody positivity in these 17 carriers was 88.2%, and the positivity in the non-carriers was 83.7%.

Conclusions

Most burn patients had antibody to TSST-1, and nasal colonization with TSST-1-producing S. aureus was associated with positive titers of anti-TSST-1 antibody. Additionally, patients with negative titers of anti-TSST-1 antibody might be susceptible to TSS.

Antibiotics and bacterial resistance in the 21st century

Dangerous, antibiotic resistant bacteria have been observed with increasing frequency over the past several decades. In this review the factors that have been linked to this phenomenon are addressed. Profiles of bacterial species that are deemed to be particularly concerning at the present time are illustrated. Factors including economic impact, intrinsic and acquired drug resistance, morbidity and mortality rates, and means of infection are taken into account. Synchronously with the waxing of bacterial resistance there has been waning antibiotic development. The approaches that scientists are employing in the pursuit of new antibacterial agents are briefly described. The standings of established antibiotic classes as well as potentially emerging classes are assessed with an emphasis on molecules that have been clinically approved or are in advanced stages of development. Historical perspectives, mechanisms of action and resistance, spectrum of activity, and preeminent members of each class are discussed.

Staphylococcus aureus toxic shock syndrome toxin-1 (TSST-1) production and Lactobacillus species growth in a defined medium simulating vaginal secretions

Lactobacillus species are commensal with the healthy vaginal environment and inhibit the growth of many pathogenic bacteria in the vaginal tract by a variety of mechanisms, such as the production of hydrogen peroxide, organic acids, and antimicrobial substances. Simulation of the vaginal environment is crucial for proper investigation of the effects of Lactobacillus species on pathogenic bacteria. In this study, we modified a medium used to simulate vaginal secretions to improve the growth of toxic shock syndrome toxin-1 (TSST-1)-producing Staphylococcus aureus clinical strains and Lactobacillus species so that interactions between these bacteria may be examined. A medium consisting of basal salts, vitamins, albumin, glycogen, mucin, urea, sodium bicarbonate, polyoxyethylene sorbitan monolaurate, and amino acids supported the growth of S. aureus and the production of TSST-1 as determined by Western analysis. Improved growth of the Lactobacillus species was seen when this same medium was supplemented with manganese chloride, sodium acetate, and an increase in glucose concentration. However, growth of S. aureus in the supplemented medium resulted in reduced levels of TSST-1. Production of TSST-1 was not detected in a medium routinely used for the growth of Lactobacillus species although S. aureus growth was not inhibited. The development of an improved genital tract secretion medium provides a more authentic environment in which to study the interactions of Lactobacillus species and vaginal pathogens, such as S. aureus.

Searching the Staphylococcal Superantigens: Enterotoxins A, B, C, and TSST1 in Synovial Fluid of Cases With Negative Culture Inflammatory Arthritis

Background:

Accurate and rapid diagnosis of bacterial arthritis is not always possible in unvaccinated (Streptococcus pneumoniae and Haemophilus influenzae type B) children in Iran.

Objectives:

Searching the staphylococcal superantigen (entrotoxin A, B, C and TSST1) in synovial fluid of cases with inflammatory arthritis.

Patients and Methods:

This cross sectional study was implemented in the pediatric and orthopedic wards, Rasoul Akram Hospital, Tehran, Iran (2008-2010) upon synovial fluid (SF) aspirated from 66 children (five months to 16 years; mean age 11 ± 3.8 years) with monoarthritis. Staphylococcal supperantigens (enterotoxins A, B, C, TSST1) were assessed by Enzyme-linked immunosorbent assay (ELISA) in synovial fluid of cases with inflammatory arthitis. Staphylococcal superantigens compared between cases with positive and negative Staphylococcus aureus culture (P < 0.05 was significant)

Results:

S. aureus was the most common cause of septic arthritis. Positive S. aureus culture in SF was reported in 10.6% (7/66) of the cases. Enterotoxin A was the least common type of superantigens found even in SF negative culture; 47% of the cases had one or more staphylococcal superantigens. Enterotoxin A was the least common type in SF; there was poor agreement between positive culture for S. aureus and presence of enterotoxins B, C, and TSST1 in SF, and intermediate agreement (KAPPA Index = 0.67) for enterotoxin A.

Conclusions:

A possible role (%47) for staphylococcal toxins was defined even in SF negative cultures obtained from monoarthritis cases. Failure in isolation of organisms might be due to natural un-growth of microorganism in synovial fluid, and previous antibiotic usage or low technical methods. It could not be determined from the data obtained in the current investigation whether or not staphylococcal toxins (superantigens) play a pathogenic role without direct invasion of the organism. It is recommend to use complementary methods for searching the S. aureus superantigens in future studies.

Superantigens of Staphylococcus aureus from patients with diabetic foot ulcers

BACKGROUND

Diabetic foot ulcer (DFU) infections are challenging. Staphylococcus aureus is the most commonly isolated pathogen in DFUs. Superantigens (SAgs) are causative in many S. aureus infections. We hypothesized both that DFU S. aureus will produce large SAg numbers, consistent with skin infections, and that certain SAgs will be overrepresented. We assessed the SAg and α-toxin profile of isolates from patients with DFU, compared with profiles of isolates from other sources.

MATERIALS

Twenty-five S. aureus isolates from patients with DFU were characterized. Polymerase chain reaction was used to detect genes for methicillin-resistance and SAgs. Some SAgs and the α-toxin were quantified. We compared the SAg profile of DFU isolates with SAg profiles of S. aureus isolates from skin lesions of patients with atopic dermatitis and from vaginal mucosa of healthy individuals.

RESULTS

Most DFU isolates were methicillin susceptible (64%), with USA100 the most common clonal group. The SAg gene profile of DFU isolates most closely resembled that of isolates from patients with atopic dermatitis, with the highest number of different SAg genes per isolate and a high prevalence of staphylococcal enterotoxin D and the enterotoxin gene cluster. DFU isolates also had a high prevalence of staphylococcal enterotoxin-like X.

CONCLUSIONS

Comparison of the SAg profile of DFU isolates to SAg profiles of skin lesion isolates and vaginal mucosa isolates revealed that the SAg profile of DFU isolates was more similar to that of skin lesion isolates. SAgs offer selective advantages in facilitating DFU infections and suggest that therapies to neutralize or reduce SAg production by S. aureus may be beneficial in management of patients with DFU.

Lesson of the month 2: toxic shock syndrome

Toxic shock syndrome (TSS) represents a fascinating example of immune activation caused by infection resulting in a dramatic and challenging clinical syndrome. TSS is commonly associated with tampon use and still causes significant morbidity and mortality in young healthy women. A misconception is that TSS presents with a skin rash and only occurs in women and children; however, it can occur in males and can present without skin changes. TSS presents initially as a febrile illness and within a few hours can progress to severe hypotension and multiple organ failure (MOF). Staphylococcus aureus and group A beta haemolytic streptococcus (GABHS) can secrete toxins from a small or hidden focus of infection and hence blood culture and sensitivity (C+S) tests can be negative, thereby making diagnosing this condition challenging. Clindamycin is superior to penicillin in the treatment of this condition and significantly decreases the mortality rate in TSS. However, there is also an important role for intravenous immunoglobulins (IVIG). Early intensive care unit (ICU) as well as surgical team involvement (in selected cases) is required to avoid mortality which may approach 70%.

Novel antimicrobial peptides that inhibit gram positive bacterial exotoxin synthesis

Gram-positive bacteria, such as Staphylococcus aureus, cause serious human illnesses through combinations of surface virulence factors and secretion of exotoxins. Our prior studies using the protein synthesis inhibitor clindamycin and signal transduction inhibitors glycerol monolaurate and α-globin and β-globin chains of hemoglobin indicate that their abilities to inhibit exotoxin production by S. aureus are separable from abilities to inhibit growth of the organism. Additionally, our previous studies suggest that inhibition of exotoxin production, in absence of ability to kill S. aureus and normal flora lactobacilli, will prevent colonization by pathogenic S. aureus, while not interfering with lactobacilli colonization. These disparate activities may be important in development of novel anti-infective agents that do not alter normal flora. We initiated studies to explore the exotoxin-synthesis-inhibition activity of hemoglobin peptides further to develop potential agents to prevent S. aureus infections. We tested synthesized α-globin chain peptides, synthetic variants of α-globin chain peptides, and two human defensins for ability to inhibit exotoxin production without significantly inhibiting S. aureus growth. All of these peptides were weakly or not inhibitory to bacterial growth. However, the peptides were inhibitory to exotoxin production with increasing activity dependent on increasing numbers of positively-charged amino acids. Additionally, the peptides could be immobilized on agarose beads or have amino acid sequences scrambled and still retain exotoxin-synthesis-inhibition. The peptides are not toxic to human vaginal epithelial cells and do not inhibit growth of normal flora L. crispatus. These peptides may interfere with plasma membrane signal transduction in S. aureus due to their positive charges.

[Staphylococcal toxic shock syndrome after breast surgery]

The surgical site infection occurs within 30 days after surgery. It is the most common complication of surgery, with a rate of 1 to 5% without antibiotic prophylaxis and less than 1% with antibiotic prophylaxis. The toxic shock syndrome (TSS) is a dramatic complication. We report the case 39-year-old woman who presented a life-threatening TSS acquired after breast surgery. We describe the signs and symptoms of this condition as well as treatment principles.

Staphylococcal and streptococcal superantigen exotoxins

SUMMARY This review begins with a discussion of the large family of Staphylococcus aureus and beta-hemolytic streptococcal pyrogenic toxin T lymphocyte superantigens from structural and immunobiological perspectives. With this as background, the review then discusses the major known and possible human disease associations with superantigens, including associations with toxic shock syndromes, atopic dermatitis, pneumonia, infective endocarditis, and autoimmune sequelae to streptococcal illnesses. Finally, the review addresses current and possible novel strategies to prevent superantigen production and passive and active immunization strategies.

Use of porcine vaginal tissue ex-vivo to model environmental effects on vaginal mucosa to toxic shock syndrome toxin-1

Menstrual toxic shock syndrome (mTSS) is a rare, recognizable, and treatable disease that has been associated with tampon use epidemiologically. It involves a confluence of microbial risk factors (Staphylococcus aureus strains that produce the superantigen-TSST-1), as well as environmental characteristics of the vaginal ecosystem during menstruation and host susceptibility factors. This paper describes a series of experiments using the well-characterized model of porcine vaginal mucosa ex-vivo to assess the effect of these factors associated with tampon use on the permeability of the mucosa. The flux of radiolabeled TSST-1 and tritiated water ((3)H2O) through porcine vaginal mucosa was determined at various temperatures, after mechanical disruption of the epithelial surface by tape stripping, after treatment with surfactants or other compounds, and in the presence of microbial virulence factors. Elevated temperatures (42, 47 and 52°C) did not significantly increase flux of (3)H2O. Stripping of the epithelial layers significantly increased the flux of labeled toxin in a dose-dependent manner. Addition of benzalkonium chloride (0.1 and 0.5%) and glycerol (4%) significantly increased the flux of (3)H2O but sodium lauryl sulfate at any concentration tested did not. The flux of the labeled toxin was significantly increased in the presence of benzalkonium chloride but not Pluronic® L92 and Tween 20 and significantly increased with addition of α-hemolysin but not endotoxin. These results show that the permeability of porcine vagina ex-vivo to labeled toxin or water can be used to evaluate changes to the vaginal environment and modifications in tampon materials, and thus aid in risk assessment.

Clinical relevance of the ESKAPE pathogens

In recent years, the Infectious Diseases Society of America has highlighted a faction of antibiotic-resistant bacteria (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter spp.) - acronymically dubbed 'the ESKAPE pathogens' - capable of 'escaping' the biocidal action of antibiotics and mutually representing new paradigms in pathogenesis, transmission and resistance. This review aims to consolidate clinically relevant background information on the ESKAPE pathogens and provide a contemporary summary of bacterial resistance, alongside pertinent microbiological considerations necessary to face the mounting threat of antimicrobial resistance.