Molecular Epidemiology of Vancomycin-Resistant Enterococci Bloodstream Infections in Germany: A Population-Based Prospective Longitudinal Study

Vancomycin-resistant enterococci (VRE) pose a public health challenge worldwide. While VRE bloodstream infections (VREBI) increase in Germany and Europe, population-based molecular data are scarce. We aimed to analyze the molecular epidemiology, demographic aspects, and geographical distribution of VREBI in the German Federal State of North-Rhine–Westphalia (NRW), located in the German–Dutch–Belgian border area, representing over 20% of Germany’s population. VREBI isolates were collected from hospitals across NRW between 2016 and 2019. Demographic data were gathered and anonymized upon sample collection. Multilocus sequence typing (MLST) and identification of glycopeptide resistance were carried out. Epidemiological analysis and geographical mapping were performed. Single VREBI isolates from 755 patients were analyzed. In total, 38.9% were female, and 80.0% were aged ≥ 60 years. The VREBI incidence per 100,000 inhabitants nearly tripled, from 0.52 (2016) to 1.48 (2019), particularly in male patients aged ≥ 50 years. The proportion of vanB reached 83% (n = 202/243) in 2018, overtaking vanA as the predominant glycopeptide resistance determinant, detected in close relation with ST117 isolates. The proportion of MLST sequence type (ST) 117 peaked in 2018, at 78.2% (n = 190/243). The major role of these emerging strains in invasive infections in central Europe requires novel strategies for their diagnosis, treatment, and prevention.

Pursuit of next-generation glycopeptides: A journey with vancomycin

Vancomycin, a blockbuster antibiotic of the glycopeptide class, has been a life-saving therapeutic against multidrug-resistant Gram-positive infections. The emergence of glycopeptide resistance has however enunciated the need to develop credible...

Analysis of the phenotypic and genotypic antimicrobial resistance profiles of clinically significant enterococci isolated in the Provincial Specialist Hospital in Lublin, Poland

The increasing significance of enterococci as healthcare-associated pathogens can be linked to their limited susceptibility to antibiotics. In this study, phenotypic and genotypic resistance profiles of 35 [n=18 E. faecium (Efm); n=17 E. faecalis (Efs)] invasive isolates cultured from hospitalized patients were analysed. Phenotypic identification was verified by the multiplex PCR targeting the 16S rDNA and the ddl genes encoding for the Efs and Efm – specific ligases. Antimicrobial susceptibility was determined using the disc diffusion method and E-tests. The high-level streptomycin resistance (HLSR), high-level gentamicin resistance (HLGR) and glycopeptide resistance was verified by amplification of the ant(6)-Ia, aac(6’)-Ie-aph(2’’)-Ia, as well as vanA and vanB genes, respectively. More than 70% of all isolates were cultured from patients in the Intensive Care and Internal Medicine Units. Blood was the predominant (77%) site of isolation. All Efm isolates were resistant to ampicillin, imipenem, and norfloxacin; 17 isolates demonstrated high-level aminoglycoside resistance (HLAR), including 27.7% with HLSR, 38.8% with HLGR and 27.7% with both phenotypes. HLAR was also common in Efs (HLSR>70%, HLGR>50%), followed by norfloxacin (64.7%) and ampicillin (11.7%) resistance. The ant(6)-Ia and aac(6’)-Ie-aph(2’’)-Ia genes were detected in >90% of the HLSR and HLGR isolates, respectively. Glycopeptide resistance was detected in 4 (22.2%) Efm isolates and mediated by the vanA gene. 19 (54.3%) isolates were multidrug resistant, including 17 (89.5%) Efm. All isolates were susceptible to linezolid. The study constitutes a contribution to the analysis of enterococcal antimicrobial resistance in Polish hospitals. The monitoring of enterococcal prevalence and antimicrobial resistance is crucial to control and prevent infections.

Genomic Insights into the Distribution and Phylogeny of Glycopeptide Resistance Determinants within the Actinobacteria Phylum

The spread of antimicrobial resistance (AMR) creates a challenge for global health security, rendering many previously successful classes of antibiotics useless. Unfortunately, this also includes glycopeptide antibiotics (GPAs), such as vancomycin and teicoplanin, which are currently being considered last-resort drugs. Emerging resistance towards GPAs risks limiting the clinical use of this class of antibiotics—our ultimate line of defense against multidrug-resistant (MDR) Gram-positive pathogens. But where does this resistance come from? It is widely recognized that the GPA resistance determinants—van genes—might have originated from GPA producers, such as soil-dwelling Gram-positive actinobacteria, that use them for self-protection. In the current work, we present a comprehensive bioinformatics study on the distribution and phylogeny of GPA resistance determinants within the Actinobacteria phylum. Interestingly, van-like genes (vlgs) were found distributed in different arrangements not only among GPA-producing actinobacteria but also in the non-producers: more than 10% of the screened actinobacterial genomes contained one or multiple vlgs, while less than 1% encoded for a biosynthetic gene cluster (BGC). By phylogenetic reconstructions, our results highlight the co-evolution of the different vlgs, indicating that the most diffused are the ones coding for putative VanY carboxypeptidases, which can be found alone in the genomes or associated with a vanS/R regulatory pair.

The Colonization of Vancomycin-Resistant Enterococcus (VRE): Prevalence, Molecular Epidemiology, and Risk Factors in Patients Admitted to Intensive Care Units in Beijing.

Background: Vancomycin-resistant Enterococcus (VRE), as an important nosocomial pathogens, can be carried in gut for a long period and its colonization status associated with the subsequent infections. The aim of this study was to investigate the frequency of intestinal VRE colonization and identify the risk factors associated with VRE carriage in intensive care patients.Methods: We conducted a 4-week cross-sectional study at six hospitals in Beijing, China. Patients admitted to Intensive Care Units (ICUs) were screened for intestinal colonization of VRE every Tuesday morning. Rectal swabs were selectively cultured for VRE, then the identified strains were analyzed by PCR to detect the glycopeptide resistance gene and were characterized by MLST. Risk factors were recorded to assess their effect on VRE acquisition during ICUs stay.Results: Of 148 patients recruited, 46 (31.1%) were colonized with VRE, with the majority (n=42) being Enterococcus faecium. In total, 78.3% of the VRE were vanA positive and 15.2% vanM positive, while 6.5% undetected glycopeptide resistance gene. The predominant ST was ST78 (47.6%) followed by ST192 (14.3%), ST555 (9.5%), ST789 (9.5%), ST547 (4.8%), and ST922 (4.8%). Risk factors associated with VRE carriage were age of >65 years, a longer length of ICU stay, use of an endotracheal tube, and prior glycopeptides use.Conclusions: The overall incidence proportion of VRE colonization at ICUs was relatively high in Beijing, and clonal expansion and horizontal transmission of resistant genes were both found here. Routine screening is necessary to prevent the dissemination of VRE.

Determination of a Tentative Epidemiological Cut-Off Value (ECOFF) for Dalbavancin and Enterococcus faecium

Dalbavancin is a lipoglycopeptide antibiotic that shows potent activity against Gram-positive bacteria. It circumvents vanB-type glycopeptide resistance mechanisms; however, data on the in vitro activity of dalbavancin for Enterococcus faecium (E. faecium) are scarce, and thus, no breakpoints are provided. In recent years, there has been a continuing shift from vanA-type to vanB-type vancomycin-resistance in enterococci in Central Europe. Therefore, we aimed to investigate the in vitro activity of dalbavancin against different van-genotypes, with particular focus on vanB-type E. faecium. Dalbavancin susceptibility was determined for 25 van-negative, 50 vanA-positive, and 101 vanB-positive clinical E. faecium isolates (typed by cgMLST). Epidemiological Cut-Off Values (ECOFFs) were determined using ECOFFinder. For vanB-type E. faecium isolates, dalbavancin MICs were similar to those of vancomycin-susceptible isolates reaching values no higher than 0.125 mg/L. ECOFFs for van-negative and vanB-positive isolates were 0.5 mg/l and 0.25 mg/L respectively. In contrast, E. faecium possessing vanA predominantly showed dalbavancin MICs >8 mg/L, therefore preventing the determination of an ECOFF. We demonstrated the potent in vitro activity of dalbavancin against vancomycin-susceptible and vanB-type E. faecium. On the basis of the observed wildtype distribution, a dalbavancin MIC of 0.25 mg/L can be suggested as a tentative ECOFF for E. faecium.

Recent pattern of antibiotic resistance in Staphylococcus aureus clinical isolates in Eastern India and the emergence of reduced susceptibility to vancomycin

PURPOSE: We aimed to determine the recent pattern of antibiotic resistance and assess the vancomycin susceptibility profile of clinical Staphylococcus aureus in view of emerging reports of vancomycin creep, reduced vancomycin susceptibility (RVS), including heterogeneous vancomycin-intermediate S. aureus (hVISA) and vancomycin-intermediate S. aureus, and vancomycin resistance in S. aureus isolates. MATERIALS AND METHODS: Consecutive, nonduplicate isolates of S. aureus between July 2015 and June 2016 were subjected to antimicrobial susceptibility testing using standard disk diffusion test or Etest as per the Clinical and Laboratory Standards Institute 2015. Detection of hVISA was done by glycopeptide resistance detection Etest according to the manufacturer's instructions in strains with vancomycin minimum inhibitory concentration of 1–2 μg/ml. RESULTS: A total of 284 S. aureus were obtained from pus (175, 61.6%), respiratory tract (31, 10.9%), urine (27, 9.5%), blood (25, 8.8%), body fluids (18, 6.3%), and catheter tips (8, 2.8%). 127 (44.7%) isolates were methicillin resistant, and 158 (55.6%) were multidrug resistant. High resistance was observed to penicillin (81.7%), erythromycin (62.3%), and ciprofloxacin (52.1%), whereas the resistance was low to gentamicin (5.3%), rifampicin (8.1%), and doxycycline (9.5%). Two hundred and fifty-one (88.3%) isolates were fully susceptible to vancomycin, whereas 33 (11.6%) demonstrated RVS. All were uniformly susceptible to linezolid, tigecycline, and daptomycin. CONCLUSIONS: A moderately high percentage of S. aureus isolates demonstrated RVS, which may limit its usefulness in methicillin-resistant isolates and may be associated with increased complications in methicillin-susceptible infections. In view of increasing glycopeptide resistance, the susceptibility status of vancomycin along with other antibiotics among clinical S. aureus isolates should be investigated periodically.

Comparison of E test GRD and vancomycin screen agar (BHI-V3 and BHI-V4) in detection of heteroresistant vancomycin intermediate staphylococcus aureus (hVISA).

Objectives: MRSA isolates with vancomycin MIC of 1-2 μg/ml have been linked with treatment failure and heteroresistant VISA phenotype. This study was aimed at comparing two screening methods i.e. GRD Etest and Vancomycin Screen agar in detection of heteroresistance. Material & Methods: The present study was carried out on 41 Methicillin Resistant Staphylococcus aureus strains isolated from different clinical specimens collected from Lahore General Hospital, Lahore. After screening for methicillin resistance, vancomycin MIC was determined by standard E test. Isolates with a vancomycin MIC of 1-2 μg/ml were screened for heteroresistance by Glycopeptide Resistance Detection (GRD) E-test and Vancomycin screen agar. Data was entered and analyzed by using SPSS version 20.0. Study Design: Comparative Study. Setting: Pathology Department of Post Graduate Medical Institute, Lahore. Period: May 2014 to May 2015. Results: When compared with E test GRD, Vancomycin screen agar (V3) showed 100% sensitivity with a 95% CI 39.76% to 100% and the specificity was 65 % with a 95 % CI 47.46% to 79.79%. Its PPV was 23% and NPV was 100% with an overall diagnostic accuracy of 68%. When compared with E test GRD, Vancomycin screen agar (V4) showed a sensitivity of 75% with a 95% CI 19.41% to 99.37% and a specificity of 86.47% with a 95% CI 71.91 to 95.59%. Its PPV was 37.5% and NPV predictive value was 96.96% with an overall diagnostic accuracy of 85.36%. Conclusion: In developing countries like Pakistan, where E tests are costly and difficult to use in routine laboratories, a screening test, which does not miss heteroresistant VISA may be of clinical use.

MASALAH KETAHANAN (RESISTENSI) VANCOMYCIN TERHADAP ENTEROCOCCI

Enterococcus adalah bakteri komensal dalam usus (colon) manusia dan binatang, dapat menyebabkan infeksi saluran kemih,endokarditis dan infeksi intra abdominal. Vancomycin-resistant enterococci (VRE) merupakan masalah kesehatan utama di berbagainegara. VRE yang merupakan cadangan (reservoir) glycopeptide resistance dianggap dapat menjangkit ke manusia melalui persentuhan(kontak) dengan binatang atau memakan (konsumsi) daging. Walaupun E. faecalis lebih sering terjadi infeksi di manusia, tetapivancomycin resistance lebih sering ditemui di isolat E. faecium. VRE merupakan patogen pada populasi imunokompromis terutamapenderita yang mendapatkan berbagai antibiotik dan menjalani rawat inap yang lama. terdapat enam tipe glycopeptide resistanceyang dilaporkan mengenai enterococcus yaitu VanA, VanB, VanC, VanD, VanE dan Vang. VRE merupakan salah satu penyebab infeksinosokomial dan kerentanannya (kemampuan resistensinya) dapat berpindah antar organisme atau spesies lainnya. Untuk itu kebijakanpengendalian infeksi (infection control) dan panduan pemberian antibiotik sangat penting diterapkan untuk mengendalikan penyebaranVRE dan organism yang rentan (resisten) terhadap berbagai obat.