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1.
Virulence ; 15(1): 2367659, 2024 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-38951957

RESUMO

Vancomycin-resistant Enterococcus faecium (E. faecium) infection is associated with higher mortality rates. Previous studies have emphasized the importance of innate immune cells and signalling pathways in clearing E. faecium, but a comprehensive analysis of host-pathogen interactions is lacking. Here, we investigated the interplay of host and E. faecium in a murine model of septic peritonitis. Following injection with a sublethal dose, we observed significantly increased murine sepsis score and histological score, decreased weight and bacterial burden, neutrophils and macrophages infiltration, and comprehensive activation of cytokine-mediated signalling pathway. In mice receiving a lethal dose, hypothermia significantly improved survival, reduced bacterial burden, cytokines, and CD86 expression of MHC-II+ recruited macrophages compared to the normothermia group. A mathematical model constructed by observational data from 80 animals, recapitulated the host-pathogen interplay, and further verified the benefits of hypothermia. These findings indicate that E. faecium triggers a severe activation of cytokine-mediated signalling pathway, and hypothermia can improve outcomes by reducing bacterial burden and inflammation.


Assuntos
Citocinas , Modelos Animais de Doenças , Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Interações Hospedeiro-Patógeno , Peritonite , Sepse , Enterococos Resistentes à Vancomicina , Animais , Peritonite/microbiologia , Peritonite/imunologia , Camundongos , Infecções por Bactérias Gram-Positivas/imunologia , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina/patogenicidade , Sepse/microbiologia , Sepse/imunologia , Citocinas/metabolismo , Camundongos Endogâmicos C57BL , Macrófagos/imunologia , Macrófagos/microbiologia , Transdução de Sinais
2.
Sci Rep ; 11(1): 11300, 2021 05 28.
Artigo em Inglês | MEDLINE | ID: mdl-34050227

RESUMO

Vancomycin-resistant enterococci (VRE) are prominent causes of nosocomial infections. Japanese traditional (Kampo) medicine promotes intestinal immunity and protects against bacterial infections. We assessed potential differences in the clinical course of VRE-positive patients, based on their characteristics and treatment with Kampo medicines. This retrospective observational study collected data from VRE-positive patients from August 2018 to July 2019 at a tertiary-care hospital in Japan. The data of 122 consecutive VRE-positive inpatients were analyzed. Sixty-nine patients were treated with probiotics, among whom, 18 were further treated with Kampo medicines. Twenty-six of the 122 patients subsequently died. In univariate analyses, subsequent VRE negative conversion significantly reduced the mortality of VRE-detected patients (p = .0003). Administration of probiotics (p = .0065) and Kampo medicines with probiotics (p = .0002), especially of the Kampo medicine hochuekkito (p = .0014), and a higher serum albumin level positively contributed to the subsequent VRE negative conversion. Multivariate analyses demonstrated that Kampo medicines and body mass index contributed to VRE negative conversion. Hochuekkito shortened the time needed for VRE negative conversion (p = 0.0485). Administration of Kampo medicines, especially of hochuekkito, in addition to probiotics in VRE patients may promote VRE negative conversion.


Assuntos
Medicamentos de Ervas Chinesas/farmacocinética , Medicina Tradicional do Leste Asiático/métodos , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana/efeitos dos fármacos , Medicamentos de Ervas Chinesas/metabolismo , Enterococcus/efeitos dos fármacos , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Japão/epidemiologia , Masculino , Medicina Tradicional Chinesa/métodos , Medicina Kampo/métodos , Pessoa de Meia-Idade , Probióticos/uso terapêutico , Estudos Retrospectivos , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/patogenicidade
3.
PLoS One ; 16(4): e0249823, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33831089

RESUMO

BACKGROUND: Vancomycin resistant enterococci (VRE) and vancomycin resistance coagulase negative staphylococci (VRCoNS) are common pathogens causing difficult to treat health care associated infections (HAI). Hence, the World Health Organization listed VRE as one of the high priority pathogens for new antibiotic discovery and antimicrobial resistance surveillance. Despite this, data on the prevalence of VRE and VRCoNS in Ethiopia is scarce. Thus, the present study determined prevalence of VRE and VRCoNS among patients attending Felege-Hiwot comprehensive specialized hospital, Ethiopia. METHODS: A hospital based cross-sectional study was conducted on 384 patients selected conveniently from February to March 2020. Data on demographic and clinical variables were collected using a structured questionnaire by face-to-face interview. Simultaneously urine, venous blood and wound swab were collected and processed following standard bacteriological technique. Antimicrobial susceptibility test was performed by minimum inhibitory concentration method using E-test for vancomycin and Kirby-Bauer disc diffusion method for other classes of antibiotics. Data was entered and analyzed using SPSS version 23. Logistic regression was performed to identify factors associated with VRE infection. P. value < 0.05 was considered as statistically significant. RESULTS: The prevalence of enterococci and CoNS were 6.8% and 12% respectively. The prevalence of VRE was 34.61% (9/26), while all CoNS (46 isolates) were susceptible to vancomycin. The majority (66.7%) of VRE was isolated from blood samples. Furthermore all VRE (100%), 58.8% of vancomycin susceptible enterococci and 45.7% of CoNS were multidrug resistant (MDR). Having educational level of secondary school and below (AOR = 12.80, CI = 1.149-142.5), previous exposure to catheterization (AOR = 56.0, CI = 4.331-724.0) and previous antibiotic use practice (AOR = 26.25, CI = 3.041-226.2) were a significant associated explanatory factor for VRE infection. CONCLUSIONS: The prevalence of vancomycin resistance enterococci, which is also multidrug resistant, was significantly high. Though no vancomycin resistance CoNS detected, the MDR level of CoNS was high. Thus to limit enterococci and CoNS infections and MDR development, focused infection prevention measures should be implemented.


Assuntos
Infecções Estafilocócicas/microbiologia , Staphylococcus/patogenicidade , Infecções Urinárias/microbiologia , Enterococos Resistentes à Vancomicina/patogenicidade , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Criança , Pré-Escolar , Coagulase/deficiência , Coagulase/metabolismo , Farmacorresistência Bacteriana Múltipla , Etiópia , Feminino , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Pacientes Ambulatoriais/estatística & dados numéricos , Prevalência , Infecções Estafilocócicas/epidemiologia , Staphylococcus/enzimologia , Staphylococcus/isolamento & purificação , Infecções Urinárias/epidemiologia , Enterococos Resistentes à Vancomicina/isolamento & purificação
4.
Hosp Top ; 99(3): 130-139, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33459211

RESUMO

Increasing cleaning time may reduce hospital-acquired transmission of Clostridioides difficile, methicillin-resistant Staphylococcus aureus (MRSA), and vancomycin-resistant enterococcus (VRE). We constructed a cost-benefit model to estimate the impact of implementing an enhanced cleaning protocol, allowing hospital housekeepers an additional 15 minutes to terminally clean contact precautions rooms. The enhanced cleaning protocol saved the hospital $758 per terminally-cleaned room when accounting for only C. difficile. Scaling up to a hospital with 100 cases of C. difficile/year, and the US annual C. difficile incidence, cost savings were $75,832/year and $169.8 million/year, respectively. These results may inform infection control strategic decision-making and resource allocation.


Assuntos
Zeladoria/normas , Controle de Infecções/economia , Quartos de Pacientes/normas , Fatores de Tempo , Clostridioides difficile/efeitos dos fármacos , Clostridioides difficile/patogenicidade , Análise Custo-Benefício/métodos , Zeladoria/economia , Zeladoria/métodos , Humanos , Controle de Infecções/métodos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Quartos de Pacientes/tendências , Melhoria de Qualidade/normas , Indicadores de Qualidade em Assistência à Saúde , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/patogenicidade
5.
mSphere ; 5(6)2020 11 18.
Artigo em Inglês | MEDLINE | ID: mdl-33208515

RESUMO

Vancomycin-resistant Enterococcus (VRE) is a leading cause of hospital-acquired infections and continues to spread despite widespread implementation of pathogen-targeted control guidelines. Commensal gut microbiota provide colonization resistance to VRE, but the role of gut microbiota in VRE acquisition in at-risk patients is unknown. To address this gap in our understanding, we performed a case-control study of gut microbiota in hospitalized patients who did (cases) and did not (controls) acquire VRE. We matched case subjects to control subjects by known risk factors and "time at risk," defined as the time elapsed between admission until positive VRE screen. We characterized gut bacterial communities using 16S rRNA gene amplicon sequencing of rectal swab specimens. We analyzed 236 samples from 59 matched case-control pairs. At baseline, case and control subjects did not differ in gut microbiota when measured by community diversity (P = 0.33) or composition (P = 0.30). After hospitalization, gut communities of cases and controls differed only in the abundance of the Enterococcus-containing operational taxonomic unit (OTU), with the gut microbiota of case subjects having more of this OTU than time-matched control subjects (P = 0.01). Otherwise, case and control communities after the time at risk did not differ in diversity (P = 0.33) or community structure (P = 0.12). Among patients who became VRE colonized, those having the Blautia-containing OTU on admission had lower Enterococcus relative abundance once colonized (P = 0.004). Our results demonstrate that the 16S profile of the gut microbiome does not predict VRE acquisition in hospitalized patients, likely due to rapid and profound microbiota change. The gut microbiome does not predict VRE acquisition, but it may be associated with Enterococcus expansion, suggesting that these should be considered two distinct processes.IMPORTANCE The Centers for Disease Control and Prevention estimates that VRE causes an estimated 54,000 infections and 539 million dollars in attributable health care costs annually. Despite improvements in hand washing, environmental cleaning, and antibiotic use, VRE is still prevalent in many hospitals. There is a pressing need to better understand the processes by which patients acquire VRE. Multiple lines of evidence suggest that intestinal microbiota may help some patients resist VRE acquisition. In this large case-control study, we compared the 16S profile of intestinal microbiota on admission in patients that did and did not subsequently acquire VRE. The 16S profile did not predict subsequent VRE acquisition, in part due to rapid and dramatic change in the gut microbiome following hospitalization. However, Blautia spp. present on admission predicted decreased Enterococcus abundance after VRE acquisition, and Lactobacillus spp. present on admission predicted Enterococcus dominance after VRE acquisition. Thus, VRE acquisition and domination may be distinct processes.


Assuntos
Enterococcus faecium/crescimento & desenvolvimento , Microbioma Gastrointestinal/fisiologia , RNA Ribossômico 16S/genética , Enterococos Resistentes à Vancomicina/crescimento & desenvolvimento , Antibacterianos/farmacologia , Fenômenos Fisiológicos Bacterianos , Estudos de Casos e Controles , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Enterococcus faecium/patogenicidade , Fezes/microbiologia , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Humanos , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/patogenicidade
6.
Sci Rep ; 10(1): 20542, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33239734

RESUMO

Vancomycin-resistant enterococci are a global challenge currently as reported by the World Health Organization. It is also important to recognize that combating antimicrobial resistance needs to recognize the interconnections between people, animals, plants and their shared environment in creating public health, the so-called One Health approach. Although the presence of VRE has been described in many regions of the world, there is a lack of comprehensive data indicating their prevalence of in Africa. Therefore, this study aimed to aggregate the result of studies describing VRE reported across multiple regions in Africa. A literature search was conducted on PubMed, Google scholar, and Hinari with the term "Vancomycin resistance enterococcus in Africa" on August 1-3, 2019. All available articles were downloaded to "Endnote version 7.1" then to Microsoft Word 2013. Articles determined to meet our criteria for the review was extracted to Microsoft Excel 2013. Those articles that reported the prevalence of vancomycin resistance Enterococcus obtained from all sample types and published from 2010 to 2019 in the English language were included for the review. A meta-analysis was conducted with OpenMetaAnalyst version R.3.1.0 software. The effect size was determined using a binary random effect model and statically significant considered when p < 0.05. Heterogeneity determined with the inconsistency index. A leave one out analysis used to perform the sensitivity analysis. There were 151 articles identified from the database searches; of this, 36 articles included after extensive review with two independent authors. Out of 4073 samples collected, 1488 isolates identified with an overall pooled prevalence of VRE 26.8% (95% CI; 10.7-43.0%) in Africa with a one-health perspective. The analysis showed that considerable heterogeneity among the studies (I2 = 99.97%; p < 0.001). Subgroup analysis in-country, African region, laboratory method, year of publication, and sample source showed that a high prevalence was identified from South Africa (74.8%), South African regions (74.8%), PCR (959.2%), 2010-2015 years (30.3%) and environmental (52.2%), respectively. This meta-analysis indicates that there was a high-pooled prevalence of vancomycin-resistant enterococci in African. A lot should be done to prevent and control the transmission of vancomycin resistance enterococci to a human being from the environment in the continent.


Assuntos
Infecções por Bactérias Gram-Positivas/epidemiologia , Enterococos Resistentes à Vancomicina/genética , África/epidemiologia , Antibacterianos , Enterococcus/genética , Humanos , Testes de Sensibilidade Microbiana , Saúde Única/tendências , Reação em Cadeia da Polimerase , Prevalência , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/patogenicidade
7.
J Clin Lab Anal ; 34(12): e23541, 2020 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-33025699

RESUMO

BACKGROUND: The aim of this study was to provide information about the spread and characteristics of the vancomycin-resistant Enterococcus faecium isolates (VREfm) in Turkey. METHODS: Seventy-one nonduplicate consecutive isolates of VREfm were obtained from various clinical specimens of inpatients treated at university or training hospitals in seven regions of Turkey. Further characteristics included antibiotic susceptibility testing, pulsed-field gel electrophoresis (PFGE) of SmaI-digested genomic DNA, and multilocus sequence typing (MLST) of selected isolates. The presence of vancomycin resistance and virulence genes (esp and hyl) was investigated by polymerase chain reaction (PCR). RESULTS: All VREfm isolates had MICs to vancomycin of ≥32 mg/L and contained the vanA gene. The presence of esp gene was identified in 64 and hyl in eight VREfm isolates. All VREfm showed the multiresistance phenotype, including ampicillin (99%), penicillin (99%), imipenem (99%), ciprofloxacin (87%), moxifloxacin (87%), erythromycin (97%), streptomycin (86%), gentamicin (82%), tetracycline (70%), and teicoplanin (99%). All were susceptible to tigecycline while quinupristin-dalfopristin (97%) and linezolid (93%) were the most active other agents. Analysis of the PFGE profiles showed that 53 (74.6%) VREfm isolates shared a similar electrophoretic profile, designed as type 1, and were closely related (>85%). The sequence type was identified by MLST in 44 VRE isolates with unrelated or closely related PFGE patterns. MLST revealed that nosocomial spread of VREfm resulted from dissemination of lineage C1 E faecium clones. Sequence types ST78, ST203, and ST117 were the most frequently isolated. This is the first report of ST733 around the world. CONCLUSIONS: Lineage C1 clones are disseminated among clinical VREfm isolates in seven different regions in Turkey. Regarding VREfm isolates, the worldwide epidemic strains are in circulation in Turkey.


Assuntos
Infecção Hospitalar , Enterococcus faecium , Infecções por Bactérias Gram-Positivas , Enterococos Resistentes à Vancomicina , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Criança , Pré-Escolar , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Estudos Transversais , Farmacorresistência Bacteriana/genética , Eletroforese em Gel de Campo Pulsado , Enterococcus faecium/classificação , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/patogenicidade , Feminino , Infecções por Bactérias Gram-Positivas/epidemiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Lactente , Masculino , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Turquia/epidemiologia , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/patogenicidade , Fatores de Virulência/genética , Adulto Jovem
8.
Indian J Med Microbiol ; 38(2): 200-209, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32883934

RESUMO

Purpose: Enterococci express high degree of resistance towards wide range of antibiotics. Production of biofilm and many virulence factors along with drug resistance makes it difficult to eradicate the infection from urinary tract. The present study detected the expression of such factors including biofilm production by multidrug-resistant (MDR) enterococci. Materials and Methods: Drug susceptibility of 103 uropathogenic enterococci was performed followed by estimation of minimum inhibitory concentration of high-level gentamicin and vancomycin by microbroth dilution method. Vancomycin-resistant genes were detected by multiplex polymerase chain reaction. Production of virulence factors such as haemagglutination, caseinase, lipase, gelatinase, haemolysin and ß-lactamase was detected by phenotypic methods in MDR strains. Biofilm production was detected by calcofluor-white fluorescence staining and semi-quantitative adherence assay. Results: 45% and 18.4% of the isolates were high-level gentamicin-resistant and vancomycin-resistant enterococci (VRE), respectively. vanA gene was detected in 14 and vanB gene in 5 strains. Biofilm, caseinase and gelatinase were the most expressed virulence factor. Expression of caseinase, gelatinase and lipase was significantly higher in Enterococcus faecalis (P < 0.05). Expression of haemagglutination, gelatinase and haemolysin among the vancomycin-resistant isolates was significantly higher (P < 0.05). Conclusion: VanA and vanB are the prevalent genotypes responsible for vancomycin resistance. The high prevalence of MDR enterococcal strains producing biofilm and virulence determinants raises concern. asa1, hyl, esp, gelE, cyl and other genes are known to express these factors and contribute to biofilm formation. Most uropathogenic enterococci expressed biofilm at moderate level and can be detected effectively by calcofluor-white staining. No correlation was noted between vancomycin resistance and biofilm production.


Assuntos
Biofilmes/crescimento & desenvolvimento , Enterococcus faecium/patogenicidade , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções Urinárias/microbiologia , Enterococos Resistentes à Vancomicina/patogenicidade , Fatores de Virulência/biossíntese , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Estudos Transversais , Farmacorresistência Bacteriana Múltipla , Enterococcus/efeitos dos fármacos , Enterococcus/isolamento & purificação , Enterococcus/metabolismo , Enterococcus/patogenicidade , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/isolamento & purificação , Enterococcus faecalis/metabolismo , Enterococcus faecalis/patogenicidade , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/isolamento & purificação , Enterococcus faecium/metabolismo , Genes Bacterianos , Humanos , Índia , Testes de Sensibilidade Microbiana , Resistência a Vancomicina/genética , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/isolamento & purificação , Enterococos Resistentes à Vancomicina/fisiologia , Virulência/genética , Fatores de Virulência/genética
9.
Proc Natl Acad Sci U S A ; 117(21): 11703-11714, 2020 05 26.
Artigo em Inglês | MEDLINE | ID: mdl-32393645

RESUMO

Patients with hematological malignancies or undergoing hematopoietic stem cell transplantation are vulnerable to colonization and infection with multidrug-resistant organisms, including vancomycin-resistant Enterococcus faecium (VREfm). Over a 10-y period, we collected and sequenced the genomes of 110 VREfm isolates from gastrointestinal and blood cultures of 24 pediatric patients undergoing chemotherapy or hematopoietic stem cell transplantation for hematological malignancy at St. Jude Children's Research Hospital. We used patient-specific reference genomes to identify variants that arose over time in subsequent gastrointestinal and blood isolates from each patient and analyzed these variants for insight into how VREfm adapted during colonization and bloodstream infection within each patient. Variants were enriched in genes involved in carbohydrate metabolism, and phenotypic analysis identified associated differences in carbohydrate utilization among isolates. In particular, a Y585C mutation in the sorbitol operon transcriptional regulator gutR was associated with increased bacterial growth in the presence of sorbitol. We also found differences in biofilm-formation capability between isolates and observed that increased biofilm formation correlated with mutations in the putative E. faecium capsular polysaccharide (cps) biosynthetic locus, with different mutations arising independently in distinct genetic backgrounds. Isolates with cps mutations showed improved survival following exposure to lysozyme, suggesting a possible reason for the selection of capsule-lacking bacteria. Finally, we observed mutations conferring increased tolerance of linezolid and daptomycin in patients who were treated with these antibiotics. Overall, this study documents known and previously undescribed ways that VREfm evolve during intestinal colonization and subsequent bloodstream infection in immunocompromised pediatric patients.


Assuntos
Enterococcus faecium , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina , Antibacterianos/farmacologia , Bacteriemia/microbiologia , Biofilmes , Criança , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/genética , Enterococcus faecium/patogenicidade , Evolução Molecular , Feminino , Microbioma Gastrointestinal/genética , Genoma Bacteriano/genética , Humanos , Hospedeiro Imunocomprometido , Masculino , Mutação/genética , Sorbitol/metabolismo , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/genética , Enterococos Resistentes à Vancomicina/patogenicidade
10.
mSphere ; 5(2)2020 04 08.
Artigo em Inglês | MEDLINE | ID: mdl-32269153

RESUMO

Vancomycin-resistant enterococci pose a threat in the clinical setting and have been linked to hospital outbreaks worldwide. In 2017, a local spread of VanA-type vancomycin-resistant enterococci (VRE) occurred in Japan, and 25 enterococcal isolates, including 14 Enterococcus faecium, 8 E. raffinosus, and 3 E. casseliflavus isolates, were identified from four inpatients. Molecular analysis of the multispecies of VanA-type VRE revealed the involvement of both the dissemination of clonally related VRE strains between patients and the horizontal transfer of plasmids harboring the vanA gene cluster between Enterococcus spp. Pulsed-field gel electrophoresis showed that the plasmid DNAs without S1 nuclease treatment were able to migrate into the gel, suggesting that the topology of the plasmid was linear. Whole-genome sequencing revealed that this plasmid, designated pELF2, was 108,102 bp long and encoded multiple antimicrobial resistance genes, including ermA and ant(9). The amino acid sequences of putative replication- and transfer-related genes were highly conserved between pELF2 and pELF1, the latter of which was the first identified enterococcal conjugative linear plasmid. On comparing the genomic structure, pELF2 showed the presence of a backbone similar to that of pELF1, especially with respect to the nucleotide sequences of both terminal ends, indicating a hybrid-type linear plasmid, possessing two different terminal structures. pELF2 possessed a broad host range and high conjugation frequencies for enterococci. The easy transfer of pELF2 to different Enterococcus spp. in vitro might explain this local spread of multiple species, highlighting the clinical threat from the spread of antimicrobial resistance by an enterococcal linear plasmid.IMPORTANCE Increasing multidrug resistance, including vancomycin resistance, in enterococci is a major concern in clinical settings. Horizontal gene transfer, such as via plasmids, has been shown to play a crucial role in the acquisition of vancomycin resistance. Among vancomycin resistance types, the VanA type is one of the most prevalent, and outbreaks caused by VanA-type vancomycin-resistant enterococci (VRE) have occurred worldwide. Here, we describe an enterococcal linear plasmid responsible for multispecies local spread of VanA-type VRE. Such a study is important because although hospital outbreaks caused by mixed enterococcal species have been reported, this particular spread indicates plasmid transfer across species. This is a crucial finding because the high risk for such a spread of antimicrobial resistance calls for regular monitoring and surveillance.


Assuntos
Proteínas de Bactérias/genética , Carbono-Oxigênio Ligases/genética , Farmacorresistência Bacteriana Múltipla/genética , Transferência Genética Horizontal , Família Multigênica , Plasmídeos/genética , Resistência a Vancomicina/genética , Enterococos Resistentes à Vancomicina/genética , Antibacterianos/farmacologia , Eletroforese em Gel de Campo Pulsado , Enterococcus/genética , Enterococcus faecium/genética , Genoma Bacteriano , Infecções por Bactérias Gram-Positivas/microbiologia , Humanos , Testes de Sensibilidade Microbiana , Enterococos Resistentes à Vancomicina/classificação , Enterococos Resistentes à Vancomicina/patogenicidade , Sequenciamento Completo do Genoma
11.
Biochim Biophys Acta Biomembr ; 1862(8): 183195, 2020 08 01.
Artigo em Inglês | MEDLINE | ID: mdl-32130974

RESUMO

The global health threat surrounding bacterial resistance has resulted in antibiotic researchers shifting their focus away from 'traditional' antibiotics and concentrating on other antimicrobial agents, including antimicrobial peptides. These low molecular weight "mini-proteins" exhibit broad-spectrum activity against bacteria, including multi-drug resistant strains, viruses, fungi and protozoa and constitute a major element of the innate-immune system of many multicellular organisms. Some naturally occurring antimicrobial peptides are lipidated and/or glycosylated and almost all antimicrobial peptides in clinical use are either lipopeptides (Daptomycin and Polymyxin E and B) or glycopeptides (Vancomycin). Lipidation, glycosylation and PEGylation are an option for improving stability and activity in serum and for reducing the rapid clearing via the kidneys and liver. Two broad-spectrum antimicrobial peptides NH2-RIRIRWIIR-CONH2 (A1) and NH2-KRRVRWIIW-CONH2 (B1) were conjugated via a linker, producing A2 and B2, to individual fatty acids of C8, C10, C12 and C14 and in addition, A2 was conjugated to either glucose, N-acetyl glucosamine, galactose, mannose, lactose or polyethylene glycol (PEG). Antimicrobial activity against two Gram-positive strains (methicillin resistant Staphylococcus aureus (MRSA) and vancomycin resistant Enterococcus faecalis (VRE)) and three Gram-negative strains (Salmonella typhimurium, E. coli and Pseudomonas aeruginosa) were determined. Activity patterns for the lipidated versions are very complex, dependent on sequence, bacteria and fatty acid. Two reciprocal effects were measured; compared to the parental peptides, some combinations led to a 16-fold improvement whereas other combinations let to a 32-fold reduction in antimicrobial activity. Glycosylation decreased antimicrobial activity by 2 to 16-fold in comparison to A1, respectively on the sugar-peptide combination. PEGylation rendered the peptide inactive. Antimicrobial activity in the presence of 25% human serum of A1 and B1 was reduced 32-fold and 8-fold, respectively. The longer chain fatty acids almost completely restored this activity; however, these fatty acids increased hemolytic activity. B1 modified with C8 increased the therapeutic index by 2-fold for four bacterial strains. Our results suggest that finding the right lipid-peptide combination can lead to improved activity in the presence of serum and potentially more effective drug candidates for animal studies. Glycosylation with the optimal sugar and numbers of sugars at the right peptide position could be an alternative route or could be used in addition to lipidation to counteract solubility and toxicity issues.


Assuntos
Antibacterianos/efeitos adversos , Anti-Infecciosos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Glicosilação/efeitos dos fármacos , Humanos , Metabolismo dos Lipídeos/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/patogenicidade , Testes de Sensibilidade Microbiana , Relação Estrutura-Atividade , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Enterococos Resistentes à Vancomicina/patogenicidade
13.
BMC Infect Dis ; 20(1): 228, 2020 Mar 18.
Artigo em Inglês | MEDLINE | ID: mdl-32188401

RESUMO

BACKGROUND: Vancomycin-resistant enterococcus (VRE) is an important cause of infection in immunocompromised populations. Few studies have described the characteristics of vanB VRE infection. We sought to describe the epidemiology, treatment and outcomes of VRE bloodstream infections (BSI) in a vanB predominant setting in malignant hematology and oncology patients. METHODS: A retrospective review was performed at two large Australian centres and spanning a 6-year period (2008-2014). Evaluable outcomes were intensive care admission (ICU) within 48 h of BSI, all-cause mortality (7 and 30 days) and length of admission. RESULTS: Overall, 106 BSI episodes were observed in 96 patients, predominantly Enterococcus faecium vanB (105/106, 99%). Antibiotics were administered for a median of 17 days prior to BSI, and 76/96 (79%) were neutropenic at BSI onset. Of patients screened before BSI onset, 49/72 (68%) were found to be colonised. Treatment included teicoplanin (59), linezolid (6), daptomycin (2) and sequential/multiple agents (21). Mortality at 30-days was 31%. On multivariable analysis, teicoplanin was not associated with mortality at 30 days. CONCLUSIONS: VRE BSI in a vanB endemic setting occurred in the context of substantive prior antibiotic use and was associated with high 30-day mortality. Targeted screening identified 68% to be colonised prior to BSI. Teicoplanin therapy was not associated with poorer outcomes and warrants further study for vanB VRE BSI in cancer populations.


Assuntos
Bacteriemia/tratamento farmacológico , Bacteriemia/epidemiologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/epidemiologia , Neoplasias/microbiologia , Enterococos Resistentes à Vancomicina , Adulto , Idoso , Antibacterianos/uso terapêutico , Austrália , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Proteínas de Bactérias , Enterococcus faecium/isolamento & purificação , Enterococcus faecium/patogenicidade , Feminino , Infecções por Bactérias Gram-Positivas/microbiologia , Infecções por Bactérias Gram-Positivas/mortalidade , Humanos , Masculino , Pessoa de Meia-Idade , Neoplasias/complicações , Estudos Retrospectivos , Resultado do Tratamento , Enterococos Resistentes à Vancomicina/patogenicidade
14.
Am J Infect Control ; 48(3): 324-326, 2020 03.
Artigo em Inglês | MEDLINE | ID: mdl-31551123

RESUMO

We evaluated the impact of discontinuing vancomycin-resistant Enterococcus (VRE) screening and use of contact precautions on the incidence of health care-associated Clostridioides difficile infection (HA-CDI) in acute teaching hospitals in Ontario, Canada. Among hospitals that stopped VRE screening and contact precaution measures, there was a significant change in HA-CDI rates after the discontinuation of practices (incidence rate ratios, 1.11; 95% confidence interval, 1.01-1.22). No change in rate was observed among hospitals that continued VRE control practices. Screening and use of contact precautions for VRE may provide hospitals additional advantages for broadened HA-CDI control and prevention.


Assuntos
Infecções por Clostridium/etiologia , Infecções por Clostridium/microbiologia , Infecção Hospitalar/etiologia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Controle de Infecções/estatística & dados numéricos , Enterococos Resistentes à Vancomicina/patogenicidade , Clostridioides/patogenicidade , Infecção Hospitalar/microbiologia , Atenção à Saúde , Instalações de Saúde , Hospitais , Humanos , Incidência , Ontário , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/efeitos dos fármacos
15.
J Hosp Infect ; 105(1): 53-63, 2020 May.
Artigo em Inglês | MEDLINE | ID: mdl-31857122

RESUMO

Preventing vancomycin-resistant enterococci (VRE) infection is a healthcare priority. However, the cost-effectiveness of VRE control interventions is unclear. The aim of this study was to synthesize evidence on economic evaluation of VRE control practices such as screening, contact precautions, patient cohorting, and others. The literature was searched from January 1985 to June 2018, and included economic evaluations of VRE control practices in hospital settings, published in English. A total of 4711 articles were screened; nine primary studies met our criteria. All studies evaluated some form of VRE screening and contact precautions, in populations ranging from single hospital wards (or select patient groups) to multiple healthcare facilities. There was significant variability in the interventions and comparisons used. Most studies (N = 7) conducted a cost-effectiveness analysis; two studies were cost-consequence studies. All economic evaluations were from the hospital perspective. Four studies found implementing enhanced VRE-specific control practices to be cost-effective/cost-saving and two studies found that discontinuing VRE-specific control practices was not cost-effective. Three studies found decreasing VRE-specific control practices to be cost-effective/cost-saving. The quality of the included studies was generally low according to the Joanna Briggs Institute (JBI) checklist for economic evaluations; major limitations included risks of bias in intervention effect estimates, and a lack of sensitivity analyses. Most studies show that some form of VRE screening and use of Contact Precautions is cost-effective. The low study quality and heterogeneity of interventions and comparators precludes definitive conclusions about the cost effectiveness of specific VRE control interventions. Additional high-quality economic evaluations are needed to strengthen the available evidence.


Assuntos
Análise Custo-Benefício , Infecção Hospitalar/economia , Infecção Hospitalar/prevenção & controle , Infecções por Bactérias Gram-Positivas/economia , Infecções por Bactérias Gram-Positivas/prevenção & controle , Controle de Infecções/economia , Hospitais/estatística & dados numéricos , Humanos , Ensaios Clínicos Controlados Aleatórios como Assunto , Enterococos Resistentes à Vancomicina/patogenicidade
16.
Probiotics Antimicrob Proteins ; 12(3): 1203-1217, 2020 09.
Artigo em Inglês | MEDLINE | ID: mdl-31758332

RESUMO

Enterococci are commensals of human and other animals' gastrointestinal tracts. Only making up a small part of the microbiota, they have not played a significant role in research, until the 1980s. Although the exact year is variable according to different geographical areas, this was the decade when vancomycin-resistant enterococci (VRE) were discovered and since then their role as causative agents of human infections has increased. Enterococcus faecium is on the WHO's list of "bacteria for which new antibiotics are urgently needed," and with no new antibiotics in development, the situation is desperate. In this review, different aspects of VRE are outlined, including the mortality caused by VRE, antibiotic resistance profiles, animal-modeling efforts, and virulence. In addition, the limitations of current antibiotic treatments for VRE and prospective new treatments, such as bacteriocins, are reviewed.


Assuntos
Bacteriocinas , Enterococcus faecalis , Enterococcus faecium , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina , Animais , Bacteriocinas/metabolismo , Bacteriocinas/farmacologia , Enterococcus faecalis/efeitos dos fármacos , Enterococcus faecalis/patogenicidade , Enterococcus faecalis/fisiologia , Enterococcus faecium/efeitos dos fármacos , Enterococcus faecium/patogenicidade , Enterococcus faecium/fisiologia , Humanos , Enterococos Resistentes à Vancomicina/patogenicidade , Enterococos Resistentes à Vancomicina/fisiologia , Virulência
17.
Int J Antimicrob Agents ; 55(3): 105828, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31669742

RESUMO

INTRODUCTION: Vancomycin-resistant enterococci (VRE) are a leading cause of nosocomial infections because of the limited number of effective therapeutic options. In an effort to repurpose FDA-approved drugs against antibiotic-resistant bacteria, auranofin has been identified as a potent drug against VRE. METHODS AND RESULTS: The present study determined that auranofin's antibacterial activity was not affected when evaluated against a higher inoculum size of VRE (~107 CFU/mL), and auranofin successfully reduced the burden of stationary phase VRE cells via a time-kill assay. In addition, auranofin reduced VRE production of key virulence factors, including proteases, lipase and haemagglutinin. The promising features of auranofin prompted evaluation of its in vivo efficacy in a lethal mouse model of VRE septicaemia. All mice receiving auranofin at 0.125 mg/kg orally, 0.125 mg/kg subcutaneously (SC) or 0.0625 mg/kg (SC) survived the lethal VRE challenge. Additionally, auranofin was superior to linezolid, the current drug of choice, in reducing VRE burden in the liver, kidneys and spleen of mice. Remarkably, auranofin successfully reduced VRE below the limit of detection in murine internal organs after 4 days of oral or subcutaneous treatment. CONCLUSION: These results indicate that auranofin warrants further investigation as a new treatment for systemic VRE infections.


Assuntos
Antibacterianos/farmacologia , Auranofina/farmacologia , Enterococos Resistentes à Vancomicina/efeitos dos fármacos , Animais , Antirreumáticos/farmacologia , Infecções por Bactérias Gram-Positivas/tratamento farmacológico , Infecções por Bactérias Gram-Positivas/microbiologia , Linezolida/farmacologia , Camundongos , Testes de Sensibilidade Microbiana , Enterococos Resistentes à Vancomicina/patogenicidade
18.
Transfusion ; 60(2): 430-435, 2020 02.
Artigo em Inglês | MEDLINE | ID: mdl-31859413

RESUMO

BACKGROUND: Vancomycin-resistant enterococci (VRE) are antibiotic-resistant organisms associated with both colonization and serious life-threatening infection in health care settings. Contamination of platelet concentrates (PCs) with Enterococcus can result in transfusion-transmitted infection. CASE PRESENTATION: This report describes the investigation of a septic transfusion case involving a 27-year-old male patient with relapsed acute leukemia who was transfused with a 5-day-old buffy coat PC pool and developed fever and rigors. DISCUSSION: Microbiology testing and pulse-field gel electrophoresis (PFGE) was done on patient blood cultures obtained from peripheral and central lines. Microbiology and molecular testing were also performed on the remaining posttransfusion PC pool, which was refrigerated for 24 hours before microbiology testing. Red blood cell (RBC) and plasma units associated with the implicated PCs were screened for microbial contamination. Patient blood cultures obtained from peripheral and central lines yielded vancomycin-resistant Enterococcus faecium. Gram stain of a sample from the platelet pool was negative but coagulase-negative Staphylococcus (CNST) and VRE were isolated on culture. Antibiotic sensitivity and PFGE profiles of several VRE isolates from the patient before and after transfusion, and the PC pool, revealed that all were closely related. Associated RBC and plasma components tested negative for microbial contamination. CONCLUSIONS: Microbiological and molecular investigations showed a relationship between VRE isolated from the patient before and after transfusion, and therefore it is postulated that a patient-to-PC retrograde contamination (from either blood or skin) occurred. As the CNST isolated from the PC pool was not isolated from patient samples, its implication in the transfusion event is unknown.


Assuntos
Enterococcus faecium/patogenicidade , Reação Transfusional/diagnóstico , Reação Transfusional/microbiologia , Enterococos Resistentes à Vancomicina/patogenicidade , Adulto , Antibacterianos/uso terapêutico , Enterococcus faecium/efeitos dos fármacos , Humanos , Masculino , Testes de Sensibilidade Microbiana , Reação Transfusional/tratamento farmacológico , Enterococos Resistentes à Vancomicina/efeitos dos fármacos
19.
Artigo em Inglês | MEDLINE | ID: mdl-31827777

RESUMO

Background: Little is known about risk factors for subsequent infections among vancomycin resistant Enterococcus faecium (VREfm) colonizers, especially characterized by concordant pulsotypes (CP) of paired colonization and infection-related isolates. Methods: This case-control study was conducted at a teaching hospital between 2011 and 2014. Targeted patients received active surveillance culture for VREfm by anal swabs at admission. Cases were those who developed VREfm infection within 180 days after colonization of VREfm. Controls were those colonized with VREfm without subsequent VREfm infection. CP were defined by similarities ≥86.7% using pulsed-field gel electrophoresis between paired colonization and infection-related isolates. Results: Ninety-seven cases and 194 controls were enrolled. By conditional multivariable logistic regression analysis, the risk factors for subsequent infection among VREfm colonizers were intensive care unit (ICU) admission (adjusted odds ratio [aOR], 9.32; 95% CI, 3.61-24.02), receipt of central venous catheters (CVC) (aOR, 3.38; 95% CI, 1.30-8.82), and utilization of third- and fourth-generation cephalosporins (aOR, 4.06; 95% CI, 1.79-9.20, and aOR, 5.32; 95% CI, 1.85- 10.29, respectively) (all P ≤ 0.01). Fifty-six (57.7%) of case patients belonged to the CP group, which were associated with ICU admission (aOR, 3.74; 95% CI, 1.38-10.13), and infection developing within 30 days after colonization (aOR, 3.34; 95% CI, 1.25-8.91). Conclusions: Among VREfm colonizers, being admitted to ICU and receiving CVC or broad spectrum cephalosporins, were the risk factors for subsequent infections. These findings highlight the importance of conducting more strict infection control measures on specific groups of VREfm colonizers.


Assuntos
Antibacterianos/farmacologia , Enterococcus faecium/efeitos dos fármacos , Infecções por Bactérias Gram-Positivas/etiologia , Infecções por Bactérias Gram-Positivas/microbiologia , Enterococos Resistentes à Vancomicina/fisiologia , Enterococos Resistentes à Vancomicina/patogenicidade , Idoso , Idoso de 80 Anos ou mais , Técnicas de Tipagem Bacteriana , Estudos de Casos e Controles , Cefalosporinas/uso terapêutico , Feminino , Hospitais de Ensino , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Fatores de Risco , Vancomicina/farmacologia , Enterococos Resistentes à Vancomicina/classificação , Dispositivos de Acesso Vascular/efeitos adversos
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