Mode and dynamics of vanA-type vancomycin resistance dissemination in Dutch hospitals

Background Enterococcus faecium is a commensal of the gastrointestinal tract of animals and humans but also a causative agent of hospital-acquired infections. Resistance against glycopeptides and to vancomycin has motivated the inclusion of E. faecium in the WHO global priority list. Vancomycin resistance can be conferred by the vanA gene cluster on the transposon Tn1546, which is frequently present in plasmids. The vanA gene cluster can be disseminated clonally but also horizontally either by plasmid dissemination or by Tn1546 transposition between different genomic locations. Methods We performed a retrospective study of the genomic epidemiology of 309 vancomycin-resistant E. faecium (VRE) isolates across 32 Dutch hospitals (2012-2015). Genomic information regarding clonality and Tn1546 characterization was extracted using hierBAPS sequence clusters (SC) and TETyper, respectively. Plasmids were predicted using gplas in combination with a network approach based on shared k-mer content. Next, we conducted a pairwise comparison between isolates sharing a potential epidemiological link to elucidate whether clonal, plasmid, or Tn1546 spread accounted for vanA-type resistance dissemination. Results On average, we estimated that 59% of VRE cases with a potential epidemiological link were unrelated which was defined as VRE pairs with a distinct Tn1546 variant. Clonal dissemination accounted for 32% cases in which the same SC and Tn1546 variants were identified. Horizontal plasmid dissemination accounted for 7% of VRE cases, in which we observed VRE pairs belonging to a distinct SC but carrying an identical plasmid and Tn1546 variant. In 2% of cases, we observed the same Tn1546 variant in distinct SC and plasmid types which could be explained by mixed and consecutive events of clonal and plasmid dissemination. Conclusions In related VRE cases, the dissemination of the vanA gene cluster in Dutch hospitals between 2012 and 2015 was dominated by clonal spread. However, we also identified outbreak settings with high frequencies of plasmid dissemination in which the spread of resistance was mainly driven by horizontal gene transfer (HGT). This study demonstrates the feasibility of distinguishing between modes of dissemination with short-read data and provides a novel assessment to estimate the relative contribution of nested genomic elements in the dissemination of vanA-type resistance.Peer reviewe

Enterococcus faecium:from microbiological insights to practical recommendations for infection control and diagnostics

Early in its evolution, Enterococcus faecium acquired traits that allowed it to become a successful nosocomial pathogen. E. faecium inherent tenacity to build resistance to antibiotics and environmental stressors that allows the species to thrive in hospital environments. The continual wide use of antibiotics in medicine has been an important driver in the evolution of E. faecium becoming a highly proficient hospital pathogen.For successful prevention and reduction of nosocomial infections with vancomycin resistant E. faecium (VREfm), it is essential to focus on reducing VREfm carriage and spread. The aim of this review is to incorporate microbiological insights of E. faecium into practical infection control recommendations, to reduce the spread of hospital-acquired VREfm (carriage and infections). The spread of VREfm can be controlled by intensified cleaning procedures, antibiotic stewardship, rapid screening of VREfm carriage focused on high-risk populations, and identification of transmission routes through accurate detection and typing methods in outbreak situations. Further, for successful management of E. faecium, continual innovation in the fields of diagnostics, treatment, and eradication is necessary

Feasibility study of ultrasound-guided resection of tongue cancer with immediate specimen examination to improve margin control - Comparison with conventional treatment

Objectives: Squamous cell carcinoma of the tongue (SCCT) is preferably treated by surgery. Free resection margins (> 5 mm) provide local control and disease-free survival. However, close (1-5 mm) and positive margins (< 1 mm) are frequently encountered. We present our first experience of in-vivo ultrasound (US) guided SCCT resections followed by ex-vivo US control on the resection specimen to obtain free margins. We compare the results with those from a hisorical cohort of 91 conventionally treated SCCT patients. Materials and methods: Ten patients with SCCT were included in a consecutive US-cohort. We aimed for a 5-10 mm margin during surgery, while we visualized the resection plane on US. Ex-vivo US measurements on the resection specimen determined whether there was any need for an immediate re-resection. US measurements were then compared with histopathology. Histopathological margins were compared with a consecutive cohort of 91 patients who had undergone conventional surgery for a SCCT. Results: In the US cohort, 70% of the margins were free. In the conventional cohort, this figure was 17% (P = 0.005). US predicted minimal histopathological margin distance with a mean +/- SD error of 1.9 +/- 1.8 mm. The mean +/- SD of the histopathological overall submucosal/deep margin distance was 7.9 +/- 2.1 mm in the US cohort and 7.0 +/- 2.2 mm in the conventional cohort (P = 0.188). Ex-vivo examination through use of US indicated an immediate re-resection, which prevented local adjuvant treatment. Conclusion: Use of US-guided SCCT resection is feasible and improves margin control

Feasibility study of ultrasound-guided resection of tongue cancer with immediate specimen examination to improve margin control - Comparison with conventional treatment

Objectives: Squamous cell carcinoma of the tongue (SCCT) is preferably treated by surgery. Free resection margins (&gt; 5 mm) provide local control and disease-free survival. However, close (1-5 mm) and positive margins (&lt; 1 mm) are frequently encountered. We present our first experience of in-vivo ultrasound (US) guided SCCT resections followed by ex-vivo US control on the resection specimen to obtain free margins. We compare the results with those from a hisorical cohort of 91 conventionally treated SCCT patients. Materials and methods: Ten patients with SCCT were included in a consecutive US-cohort. We aimed for a 5-10 mm margin during surgery, while we visualized the resection plane on US. Ex-vivo US measurements on the resection specimen determined whether there was any need for an immediate re-resection. US measurements were then compared with histopathology. Histopathological margins were compared with a consecutive cohort of 91 patients who had undergone conventional surgery for a SCCT. Results: In the US cohort, 70% of the margins were free. In the conventional cohort, this figure was 17% (P = 0.005). US predicted minimal histopathological margin distance with a mean +/- SD error of 1.9 +/- 1.8 mm. The mean +/- SD of the histopathological overall submucosal/deep margin distance was 7.9 +/- 2.1 mm in the US cohort and 7.0 +/- 2.2 mm in the conventional cohort (P = 0.188). Ex-vivo examination through use of US indicated an immediate re-resection, which prevented local adjuvant treatment. Conclusion: Use of US-guided SCCT resection is feasible and improves margin control.</p

Genomic rearrangements uncovered by genome-wide co-evolution analysis of a major nosocomial pathogen, Enterococcus faecium

Enterococcus faecium is a gut commensal of the gastro-digestive tract, but also known as nosocomial pathogen among hospitalized patients. Population genetics based on whole-genome sequencing has revealed that E. faecium strains from hospitalized patients form a distinct Glade, designated Glade A1, and that plasmids are major contributors to the emergence of nosocomial E. faecium. Here we further explored the adaptive evolution of E faecium using a genome-wide co-evolution study (GWES) to identify co-evolving single-nucleotide polymorphisms (SNPs). We identified three genomic regions harbouring large numbers of SNPs in tight linkage that are not proximal to each other based on the completely assembled chromosome of the Glade A1 reference hospital isolate AUS0004. Close examination of these regions revealed that they are located at the borders of four different types of large-scale genomic rearrangements, insertion sites of two different genomic islands and an IS30-like transposon. In non-Glade A1 isolates, these regions are adjacent to each other and they lack the insertions of the genomic islands and IS30-like transposon. Additionally, among the Glade A1 isolates there is one group of pet isolates lacking the genomic rearrangement and insertion of the genomic islands, suggesting a distinct evolutionary trajectory. In silico analysis of the biological functions of the genes encoded in three regions revealed a common link to a stress response. This suggests that these rearrangements may reflect adaptation to the stringent conditions in the hospital environment, such as antibiotics and detergents, to which bacteria are exposed. In conclusion, to our knowledge, this is the first study using GWES to identify genomic rearrangements, suggesting that there is considerable untapped potential to unravel hidden evolutionary signals from population genomic data.Peer reviewe

Recent Recombination Events in the Core Genome Are Associated with Adaptive Evolution in Enterococcus faecium

Peer reviewe

REVISITING ANNA MOSCOWITZ\u27S KROSS\u27S CRITIQUE OF NEW YORK CITY\u27S WOMEN\u27S COURT: THE CONTINUED PROBLEM OF SOLVING THE PROBLEM OF PROSTITUTION WITH SPECIALIZED CRIMINAL COURTS

This article explores New York City\u27s non-traditional, judicially based response to prostitution. This article first recounts the history of New York City’s Women’s Court. It then examines the work of the Midtown Community Court, the “problem-solving court” established in 1993 to address criminal issues, like prostitution, in Midtown Manhattan. It also discusses the renewed concerns about sex work in New York and describe the movement, propelled by modern reformers, to address prostitution through specialty courts. It then contrasts the shared features and attributes of the Women’s Court and Midtown Court models. Finally, the article urges modern reformers to step back from the problem-solving court movement and their call for the creation of more such specialized criminal courts

mlplasmids : a user-friendly tool to predict plasmid- and chromosome-derived sequences for single species

Assembly of bacterial short-read whole-genome sequencing data frequently results in hundreds of contigs for which the origin, plasmid or chromosome, is unclear. Complete genomes resolved by long-read sequencing can be used to generate and label short-read contigs. These were used to train several popular machine learning methods to classify the origin of contigs from Enterococcus faecium, Klebsiella pneumoniae and Escherichia colt using pentamer frequencies. We selected support-vector machine (SVM) models as the best classifier for all three bacterial species (Fl-score E. faecium=0.92, F1-score K. pneumoniae=0.90, F1-score E. coli=0.76), which outperformed other existing plasmid prediction tools using a benchmarking set of isolates. We demonstrated the scalability of our models by accurately predicting the plasmidome of a large collection of 1644 E. faecium isolates and illustrate its applicability by predicting the location of antibiotic-resistance genes in all three species. The SVM classifiers are publicly available as an R package and graphical-user interface called 'mlplasmids'. We anticipate that this tool may significantly facilitate research on the dissemination of plasmids encoding antibiotic resistance and/or contributing to host adaptation.Peer reviewe

gplas : a comprehensive tool for plasmid analysis using short-read graphs

aSummary: Plasmids can horizontally transmit genetic traits, enabling rapid bacterial adaptation to new environments and hosts. Short-read whole-genome sequencing data are often applied to large-scale bacterial comparative genomics projects but the reconstruction of plasmids from these data is facing severe limitations, such as the inability to distinguish plasmids from each other in a bacterial genome. We developed gplas, a new approach to reliably separate plasmid contigs into discrete components using sequence composition, coverage, assembly graph information and network partitioning based on a pruned network of plasmid unitigs. Gplas facilitates the analysis of large numbers of bacterial isolates and allows a detailed analysis of plasmid epidemiology based solely on short-read sequence data.Peer reviewe