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1.
Nucleic Acids Res ; 51(W1): W493-W500, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37207327

RESUMO

Metagenomics can be used to monitor the spread of antibiotic resistance genes (ARGs). ARGs found in databases such as ResFinder and CARD primarily originate from culturable and pathogenic bacteria, while ARGs from non-culturable and non-pathogenic bacteria remain understudied. Functional metagenomics is based on phenotypic gene selection and can identify ARGs from non-culturable bacteria with a potentially low identity shared with known ARGs. In 2016, the ResFinderFG v1.0 database was created to collect ARGs from functional metagenomics studies. Here, we present the second version of the database, ResFinderFG v2.0, which is available on the Center of Genomic Epidemiology web server (https://cge.food.dtu.dk/services/ResFinderFG/). It comprises 3913 ARGs identified by functional metagenomics from 50 carefully curated datasets. We assessed its potential to detect ARGs in comparison to other popular databases in gut, soil and water (marine + freshwater) Global Microbial Gene Catalogues (https://gmgc.embl.de). ResFinderFG v2.0 allowed for the detection of ARGs that were not detected using other databases. These included ARGs conferring resistance to beta-lactams, cycline, phenicol, glycopeptide/cycloserine and trimethoprim/sulfonamide. Thus, ResFinderFG v2.0 can be used to identify ARGs differing from those found in conventional databases and therefore improve the description of resistomes.


Assuntos
Antibacterianos , Bases de Dados Genéticas , Resistência Microbiana a Medicamentos , Metagenômica , Antibacterianos/farmacologia , Bactérias/genética , Resistência Microbiana a Medicamentos/genética , Genes Bacterianos , Internet
2.
Antimicrob Agents Chemother ; 68(4): e0145923, 2024 Apr 03.
Artigo em Inglês | MEDLINE | ID: mdl-38441061

RESUMO

Beta-lactamase-mediated degradation of beta-lactams is the most common mechanism of beta-lactam resistance in Gram-negative bacteria. Beta-lactamase-encoding genes can be transferred between closely related bacteria, but spontaneous inter-phylum transfers (between distantly related bacteria) have never been reported. Here, we describe an extended-spectrum beta-lactamase (ESBL)-encoding gene (blaMUN-1) shared between the Pseudomonadota and Bacteroidota phyla. An Escherichia coli strain was isolated from a patient in Münster (Germany). Its genome was sequenced. The ESBL-encoding gene (named blaMUN-1) was cloned, and the corresponding enzyme was characterized. The distribution of the gene among bacteria was investigated using the RefSeq Genomes database. The frequency and relative abundance of its closest homolog in the global microbial gene catalog (GMGC) were analyzed. The E. coli strain exhibited two distinct morphotypes. Each morphotype possessed two chromosomal copies of the blaMUN-1 gene, with one morphotype having two additional copies located on a phage-plasmid p0111. Each copy was located within a 7.6-kb genomic island associated with mobility. blaMUN-1 encoded for an extended-spectrum Ambler subclass A2 beta-lactamase with 43.0% amino acid identity to TLA-1. blaMUN-1 was found in species among the Bacteroidales order and in Sutterella wadsworthensis (Pseudomonadota). Its closest homolog in GMGC was detected frequently in human fecal samples. This is, to our knowledge, the first reported instance of inter-phylum transfer of an ESBL-encoding gene, between the Bacteroidota and Pseudomonadota phyla. Although the gene was frequently detected in the human gut, inter-phylum transfer was rare, indicating that inter-phylum barriers are effective in impeding the spread of ESBL-encoding genes, but not entirely impenetrable.


Assuntos
Infecções por Escherichia coli , Escherichia coli , Humanos , beta-Lactamases/genética , beta-Lactamases/metabolismo , Infecções por Escherichia coli/microbiologia , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
3.
Bull World Health Organ ; 101(10): 672-678, 2023 Oct 01.
Artigo em Inglês | MEDLINE | ID: mdl-37772195

RESUMO

The World Health Organization developed the Tricycle surveillance programme to obtain a global picture of antimicrobial resistance, especially in countries with limited surveillance capacity. The programme was developed within a One Health perspective. Tricycle provides a framework for applying a standardized technical protocol to determining the prevalence of extended-spectrum ß-lactamase (ESBL)-producing Escherichia coli in three sectors: the human, animal and environment sectors. Regular use of the protocol would enable information to be obtained on time trends and on inter- and intraregional variations, thereby generating dynamic data on antibacterial resistance for decision-makers. To date, 19 countries have begun implementing the Tricycle protocol, while other countries will start implementation in the coming years. The Network for Enhancing Tricycle ESBL Surveillance Efficiency (NETESE) was established to support countries implementing the Tricycle protocol. Currently, NETESE includes representatives from 15 institutions in eight low- or middle-income countries at different stages of Tricycle protocol implementation, and from four European countries involved in devising the protocol. This paper describes the Tricycle protocol, reports the initial experiences of NETESE participants with its implementation and discusses future challenges and opportunities.


L'Organisation mondiale de la Santé a développé le programme de surveillance Tricycle afin d'avoir une vue globale de la résistance aux antimicrobiens, en particulier dans les pays où les capacités de surveillance sont limitées. Ce programme a été mis au point selon l'approche «One Health¼. Tricycle établit le cadre d'application d'un protocole technique standardisé qui vise à mesurer la prévalence de souches d'Escherichia coli productrices de ß-lactamase à spectre étendu (BLSE) dans trois secteurs: humain, animal et environnemental. L'usage régulier du protocole permettrait d'obtenir des informations sur l'évolution dans le temps et les variations inter- et intrarégionales, ce qui générerait des données dynamiques sur la résistance aux antimicrobiens pour les décideurs. À ce jour, 19 pays se sont lancés dans la mise en place du protocole Tricycle, tandis que d'autres prévoient de le faire dans les années à venir. Le réseau NETESE (Network for Enhancing Tricycle ESBL Surveillance Efficiency) a été créé pour les aider à appliquer ce protocole. Actuellement, le réseau NETESE réunit des représentants de 15 institutions dans huit pays à revenu faible ou intermédiaire à différents stades de mise en œuvre du protocole Tricycle, ainsi que quatre pays européens impliqués dans sa conception. Le présent document décrit le protocole Tricycle, partage les premières expériences des participants au réseau NETESE en matière de déploiement, et aborde les futurs défis et opportunités qui y sont liés.


La Organización Mundial de la Salud desarrolló el programa de vigilancia Tricycle para obtener un panorama global de la resistencia a los antimicrobianos, especialmente en países con una capacidad de vigilancia limitada. El programa se creó desde la perspectiva One Health. Tricycle proporciona un marco que permite aplicar un protocolo técnico estandarizado con el fin de determinar la prevalencia de Escherichia coli productora de ß-lactamasa de espectro extendido (ESBL) en tres sectores: el humano, el animal y el medio ambiente. El uso habitual del protocolo permitiría obtener información sobre las tendencias temporales y las variaciones inter e intrarregionales, generando así datos dinámicos sobre la resistencia a los antibacterianos que resultarían útiles para los responsables de la toma de decisiones. Hasta la fecha, 19 países han comenzado a implementar el protocolo Tricycle, mientras que otros países comenzarán a aplicarlo en los próximos años. La red NETESE (Network for Enhancing Tricycle ESBL Surveillance Efficiency), se creó para apoyar a los países que implementan el protocolo Tricycle. Actualmente, NETESE está formada por representantes de 15 instituciones de ocho países con ingresos medios o bajos, que se encuentran en diferentes etapas de implementación del protocolo Tricycle. También incluye a representantes de cuatro países europeos que intervienen en el diseño del protocolo. El presente documento describe el protocolo Tricycle, recoge las primeras experiencias de los participantes de NETESE durante la implementación de dicho protocolo, y aborda tanto los retos como las oportunidades futuras.


Assuntos
Antibacterianos , Infecções por Escherichia coli , Animais , Humanos , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , beta-Lactamases , Farmacorresistência Bacteriana , Escherichia coli
4.
Crit Care ; 26(1): 300, 2022 10 03.
Artigo em Inglês | MEDLINE | ID: mdl-36192756

RESUMO

BACKGROUND: The composition of the digestive microbiota may be associated with outcome and infections in patients admitted to the intensive care unit (ICU). The dominance by opportunistic pathogens (such as Enterococcus) has been associated with death. However, whether this association remains all throughout the hospitalization are lacking. METHODS: We performed a single-center observational prospective cohort study in critically ill patients admitted with severe SARS-CoV-2 infection. Oropharyngeal and rectal swabs were collected at admission and then twice weekly until discharge or death. Quantitative cultures for opportunistic pathogens were performed on oropharyngeal and rectal swabs. The composition of the intestinal microbiota was assessed by 16S rDNA sequencing. Oropharyngeal and intestinal concentrations of opportunistic pathogens, intestinal richness and diversity were entered into a multivariable Cox model as time-dependent covariates. The primary outcome was death at day 90. RESULTS: From March to September 2020, 95 patients (765 samples) were included. The Simplified Acute Physiology Score 2 (SAPS 2) at admission was 33 [24; 50] and a Sequential Organ Failure Assessment score (SOFA score) at 6 [4; 8]. Day 90 all-cause mortality was 44.2% (42/95). We observed that the oropharyngeal and rectal concentrations of Enterococcus spp., Staphylococcus aureus and Candida spp. were associated with a higher risk of death. This association remained significant after adjustment for prognostic covariates (age, chronic disease, daily antimicrobial agent use and daily SOFA score). A one-log increase in Enterococcus spp., S. aureus and Candida spp. in oropharyngeal or rectal swabs was associated with a 17% or greater increase in the risk of death. CONCLUSION: We found that elevated oropharyngeal/intestinal Enterococcus spp. S. aureus and Candida spp. concentrations, assessed by culture, are associated with mortality, independent of age, organ failure, and antibiotic therapy, opening prospects for simple and inexpensive microbiota-based markers for the prognosis of critically ill SARS-CoV-2 patients.


Assuntos
COVID-19 , SARS-CoV-2 , Adulto , Antibacterianos , Candida , Estado Terminal , DNA Ribossômico , Humanos , Unidades de Terapia Intensiva , Estudos Prospectivos , Staphylococcus aureus
5.
Eur J Clin Microbiol Infect Dis ; 40(10): 2227-2234, 2021 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33733394

RESUMO

Because the diagnosis of co/superinfection in COVID-19 patients is challenging, empirical antibiotic therapy is frequently initiated until microbiological analysis results. We evaluated the performance and the impact of the BioFire® FilmArray® Pneumonia plus Panel on 112 respiratory samples from 67 COVID-19 ICU patients suspected of co/superinfections. Globally, the sensitivity and specificity of the test were 89.3% and 99.1%, respectively. Positive tests led to antibiotic initiation or adaptation in 15% of episodes and de-escalation in 4%. When negative, 28% of episodes remained antibiotic-free (14% no initiation, 14% withdrawal). Rapid multiplex PCRs can help to improve antibiotic stewardship by administering appropriate antibiotics earlier and avoiding unnecessary prescriptions.


Assuntos
Antibacterianos/uso terapêutico , Bactérias/isolamento & purificação , Infecções Bacterianas/tratamento farmacológico , COVID-19/complicações , Reação em Cadeia da Polimerase Multiplex/métodos , Idoso , Gestão de Antimicrobianos , Bactérias/classificação , Bactérias/efeitos dos fármacos , Bactérias/genética , Infecções Bacterianas/diagnóstico , Infecções Bacterianas/microbiologia , COVID-19/virologia , Feminino , Hospitalização , Humanos , Unidades de Terapia Intensiva/estatística & dados numéricos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , SARS-CoV-2/genética , SARS-CoV-2/fisiologia
6.
J Antimicrob Chemother ; 75(12): 3491-3500, 2020 12 01.
Artigo em Inglês | MEDLINE | ID: mdl-32780112

RESUMO

OBJECTIVES: WGS-based antimicrobial susceptibility testing (AST) is as reliable as phenotypic AST for several antimicrobial/bacterial species combinations. However, routine use of WGS-based AST is hindered by the need for bioinformatics skills and knowledge of antimicrobial resistance (AMR) determinants to operate the vast majority of tools developed to date. By leveraging on ResFinder and PointFinder, two freely accessible tools that can also assist users without bioinformatics skills, we aimed at increasing their speed and providing an easily interpretable antibiogram as output. METHODS: The ResFinder code was re-written to process raw reads and use Kmer-based alignment. The existing ResFinder and PointFinder databases were revised and expanded. Additional databases were developed including a genotype-to-phenotype key associating each AMR determinant with a phenotype at the antimicrobial compound level, and species-specific panels for in silico antibiograms. ResFinder 4.0 was validated using Escherichia coli (n = 584), Salmonella spp. (n = 1081), Campylobacter jejuni (n = 239), Enterococcus faecium (n = 106), Enterococcus faecalis (n = 50) and Staphylococcus aureus (n = 163) exhibiting different AST profiles, and from different human and animal sources and geographical origins. RESULTS: Genotype-phenotype concordance was ≥95% for 46/51 and 25/32 of the antimicrobial/species combinations evaluated for Gram-negative and Gram-positive bacteria, respectively. When genotype-phenotype concordance was <95%, discrepancies were mainly linked to criteria for interpretation of phenotypic tests and suboptimal sequence quality, and not to ResFinder 4.0 performance. CONCLUSIONS: WGS-based AST using ResFinder 4.0 provides in silico antibiograms as reliable as those obtained by phenotypic AST at least for the bacterial species/antimicrobial agents of major public health relevance considered.


Assuntos
Antibacterianos , Farmacorresistência Bacteriana , Animais , Antibacterianos/farmacologia , Genótipo , Humanos , Testes de Sensibilidade Microbiana , Fenótipo
7.
J Infect Dis ; 217(4): 628-636, 2018 01 30.
Artigo em Inglês | MEDLINE | ID: mdl-29186529

RESUMO

Background: Antibiotics are life-saving drugs but severely affect the gut microbiome with short-term consequences including diarrhea and selection of antibiotic-resistant bacteria. Long-term links to allergy and obesity are also suggested. We devised a product, DAV132, and previously showed its ability to deliver a powerful adsorbent, activated charcoal, in the late ileum of human volunteers. Methods: We performed a randomized controlled trial in 28 human volunteers treated with a 5-day clinical regimen of the fluoroquinolone antibiotic moxifloxacin in 2 parallel groups, with or without DAV132 coadministration. Two control goups of 8 volunteers each receiving DAV132 alone, or a nonactive substitute, were added. Results: The coadministration of DAV132 decreased free moxifloxacin fecal concentrations by 99%, while plasmatic levels were unaffected. Shotgun quantitative metagenomics showed that the richness and composition of the intestinal microbiota were largely preserved in subjects co-treated with DAV132 in addition to moxifloxacin. No adverse effect was observed. In addition, DAV132 efficiently adsorbed a wide range of clinically relevant antibiotics ex vivo. Conclusions: DAV132 was highly effective to protect the gut microbiome of moxifloxacin-treated healthy volunteers and may constitute a clinical breakthrough by preventing adverse health consequences of a wide range of antibiotic treatments. Clinical Trials Registration: NCT02176005.


Assuntos
Antibacterianos/administração & dosagem , Carvão Vegetal/administração & dosagem , Microbioma Gastrointestinal/efeitos dos fármacos , Microbiota/efeitos dos fármacos , Moxifloxacina/administração & dosagem , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/análise , Fezes/química , Fezes/microbiologia , Feminino , Voluntários Saudáveis , Humanos , Masculino , Metagenômica , Pessoa de Meia-Idade , Moxifloxacina/análise , Resultado do Tratamento , Adulto Jovem
9.
Eur J Clin Microbiol Infect Dis ; 37(11): 2201-2210, 2018 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-30145620

RESUMO

The aims of the present study were to characterize the mechanisms of resistance to fluoroquinolones, macrolides, and imipenem in Haemophilus influenzae, to assess the extent of the AcrAB-TolC-mediated resistance, and to define a core genome multilocus sequence typing (cgMLST) scheme for H. influenzae by using whole-genome sequencing. Four amino acid substitutions in GyrA (at Ser84 and Asp88), ParC (at Ser84), and ParE (at Asp420) were found to be closely associated to the MICs. We did not find any amino acid substitution surrounding the three highly conserved amino acid motifs in PBP3 related to imipenem resistance. All the isolates possessed the ermB gene. Carbonyl cyanide m-chlorophenylhydrazone (CCCP) decreased the MIC of imipenem by twofold for FQR-6 and fourfold for GE47 and GE88 strains. For erythromycin, the MICs were decreased by twofold. We found that the six FQR isolates were clustered in two groups. The number of different loci within FQR-1_FQR-3_FQR-5 cluster was 6, while FQR-2 and FQR-4 differed for 21 loci. FQR-1_FQR-3_FQR-5 and FQR-2_FQR-4 clusters were distant among each other and compared to 19 genomes downloaded from NCBI, to 8 strains heteroresistant to imipenem, and to 4 strains monoresistant to ciprofloxacin isolated in Denmark. We confirmed that specific amino acid substitutions in GyrA, ParC, and ParE are implicated in quinolone resistance. Additionally, the degree of resistance is related to the number of these amino acid substitutions. We provide robust evidence that drug efflux is one of the substantial mechanisms of imipenem and erythromycin resistance in H. influenzae.


Assuntos
Fluoroquinolonas/farmacologia , Infecções por Haemophilus/microbiologia , Haemophilus influenzae/efeitos dos fármacos , Haemophilus influenzae/genética , Imipenem/farmacologia , Macrolídeos/farmacologia , Adulto , Idoso , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Feminino , Genoma Bacteriano , Genômica/métodos , Haemophilus influenzae/classificação , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Tipagem de Sequências Multilocus , Mutação , Sorogrupo , Sequenciamento Completo do Genoma
10.
Int J Mol Sci ; 18(9)2017 Sep 20.
Artigo em Inglês | MEDLINE | ID: mdl-28930150

RESUMO

The applications of whole-metagenome shotgun sequencing (WMGS) in routine clinical analysis are still limited. A combination of a DNA extraction procedure, sequencing, and bioinformatics tools is essential for the removal of human DNA and for improving bacterial species identification in a timely manner. We tackled these issues with a broncho-alveolar lavage (BAL) sample from an immunocompromised patient who had developed severe chronic pneumonia. We extracted DNA from the BAL sample with protocols based either on sequential lysis of human and bacterial cells or on the mechanical disruption of all cells. Metagenomic libraries were sequenced on Illumina HiSeq platforms. Microbial community composition was determined by k-mer analysis or by mapping to taxonomic markers. Results were compared to those obtained by conventional clinical culture and molecular methods. Compared to mechanical cell disruption, a sequential lysis protocol resulted in a significantly increased proportion of bacterial DNA over human DNA and higher sequence coverage of Mycobacterium abscessus, Corynebacterium jeikeium and Rothia dentocariosa, the bacteria reported by clinical microbiology tests. In addition, we identified anaerobic bacteria not searched for by the clinical laboratory. Our results further support the implementation of WMGS in clinical routine diagnosis for bacterial identification.


Assuntos
Bactérias/genética , Líquido da Lavagem Broncoalveolar/microbiologia , DNA Bacteriano/genética , Sequenciamento de Nucleotídeos em Larga Escala/métodos , Adulto , Bactérias/classificação , Bactérias/isolamento & purificação , DNA Bacteriano/química , DNA Bacteriano/isolamento & purificação , Humanos , Masculino , Metagenoma/genética , Reprodutibilidade dos Testes , Especificidade da Espécie
11.
Antimicrob Agents Chemother ; 60(1): 507-14, 2016 01.
Artigo em Inglês | MEDLINE | ID: mdl-26552974

RESUMO

Epidemiological and individual risk factors for colonization by enterobacteria producing extended-spectrum beta-lactamases (E-ESBL) have been studied extensively, but whether such colonization is associated with significant changes in the composition of the rest of the microbiota is still unknown. To address this issue, we assessed in an isolated Amerindian Guianese community whether intestinal carriage of E-ESBL was associated with specificities in gut microbiota using metagenomic and metatranscriptomic approaches. While the richness of taxa of the active microbiota of carriers was similar to that of noncarriers, the taxa were less homogeneous. In addition, species of four genera, Desulfovibrio, Oscillospira, Parabacteroides, and Coprococcus, were significantly more abundant in the active microbiota of noncarriers than in the active microbiota of carriers, whereas such was the case only for species of Desulfovibrio and Oscillospira in the total microbiota. Differential genera in noncarrier microbiota could either be associated with resistance to colonization or be the consequence of the colonization by E-ESBL.


Assuntos
Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/genética , Microbioma Gastrointestinal/genética , Genes Bacterianos , Indígenas Norte-Americanos , Transcriptoma , beta-Lactamases/genética , Adulto , Idoso , Portador Sadio , Desulfovibrio/genética , Desulfovibrio/isolamento & purificação , Enterobacteriaceae/classificação , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Fezes/microbiologia , Feminino , Guiana Francesa/epidemiologia , Expressão Gênica , Humanos , Masculino , Metagenoma , Pessoa de Meia-Idade , Filogenia , RNA Ribossômico 16S/genética , Análise de Sequência de DNA , beta-Lactamases/metabolismo
13.
Clin Infect Dis ; 61(4): 593-600, 2015 Aug 15.
Artigo em Inglês | MEDLINE | ID: mdl-25904368

RESUMO

BACKGROUND: Multidrug-resistant Enterobacteriaceae (MRE) are widespread in the community, especially in tropical regions. Travelers are at risk of acquiring MRE in these regions, but the precise extent of the problem is not known. METHODS: From February 2012 to April 2013, travelers attending 6 international vaccination centers in the Paris area prior to traveling to tropical regions were asked to provide a fecal sample before and after their trip. Those found to have acquired MRE were asked to send fecal samples 1, 2, 3, 6, and 12 months after their return, or until MRE was no longer detected. The fecal relative abundance of MRE among all Enterobacteriaceae was determined in each carrier. RESULTS: Among 824 participating travelers, 574 provided fecal samples before and after travel and were not MRE carriers before departure. Of these, 292 (50.9%) acquired an average of 1.8 MRE. Three travelers (0.5%) acquired carbapenemase-producing Enterobacteriaceae. The acquisition rate was higher in Asia (142/196 [72.4%]) than in sub-Saharan Africa (93/195 [47.7%]) or Latin America (57/183 [31.1%]). MRE acquisition was associated with the type of travel, diarrhea, and exposure to ß-lactams during the travel. Three months after return, 4.7% of the travelers carried MRE. Carriage lasted longer in travelers returning from Asia and in travelers with a high relative abundance of MRE at return. CONCLUSIONS: MRE acquisition is very frequent among travelers to tropical regions. Travel to these regions should be considered a risk factor of MRE carriage during the first 3 months after return, but not beyond. CLINICAL TRIALS REGISTRATION: NCT01526187.


Assuntos
Portador Sadio/epidemiologia , Portador Sadio/microbiologia , Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/isolamento & purificação , Viagem , Adolescente , Adulto , Idoso , Enterobacteriaceae/efeitos dos fármacos , Fezes/microbiologia , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Paris/epidemiologia , Fatores de Tempo , Clima Tropical , Adulto Jovem
14.
Appl Environ Microbiol ; 82(5): 1459-1467, 2015 Dec 28.
Artigo em Inglês | MEDLINE | ID: mdl-26712551

RESUMO

At a human/livestock/wildlife interface, Escherichia coli populations were used to assess the risk of bacterial and antibiotic resistance dissemination between hosts. We used phenotypic and genotypic characterization techniques to describe the structure and the level of antibiotic resistance of E. coli commensal populations and the resistant Enterobacteriaceae carriage of sympatric African buffalo (Syncerus caffer caffer) and cattle populations characterized by their contact patterns in the southern part of Hwange ecosystem in Zimbabwe. Our results (i) confirmed our assumption that buffalo and cattle share similar phylogroup profiles, dominated by B1 (44.5%) and E (29.0%) phylogroups, with some variability in A phylogroup presence (from 1.9 to 12%); (ii) identified a significant gradient of antibiotic resistance from isolated buffalo to buffalo in contact with cattle and cattle populations expressed as the Murray score among Enterobacteriaceae (0.146, 0.258, and 0.340, respectively) and as the presence of tetracycline-, trimethoprim-, and amoxicillin-resistant subdominant E. coli strains (0, 5.7, and 38%, respectively); (iii) evidenced the dissemination of tetracycline, trimethoprim, and amoxicillin resistance genes (tet, dfrA, and blaTEM-1) in 26 isolated subdominant E. coli strains between nearby buffalo and cattle populations, that led us (iv) to hypothesize the role of the human/animal interface in the dissemination of genetic material from human to cattle and toward wildlife. The study of antibiotic resistance dissemination in multihost systems and at anthropized/natural interface is necessary to better understand and mitigate its multiple threats. These results also contribute to attempts aiming at using E. coli as a tool for the identification of pathogen transmission pathway in multihost systems.


Assuntos
Farmacorresistência Bacteriana , Infecções por Escherichia coli/veterinária , Escherichia coli/classificação , Escherichia coli/efeitos dos fármacos , Animais , Antibacterianos/farmacologia , Bovinos , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/epidemiologia , Infecções por Escherichia coli/microbiologia , Variação Genética , Genótipo , Humanos , Filogenia , Zimbábue/epidemiologia
15.
Microbiome ; 12(1): 50, 2024 Mar 12.
Artigo em Inglês | MEDLINE | ID: mdl-38468305

RESUMO

BACKGROUND: Antibiotics notoriously perturb the gut microbiota. We treated healthy volunteers either with cefotaxime or ceftriaxone for 3 days, and collected in each subject 12 faecal samples up to day 90. Using untargeted and targeted phenotypic and genotypic approaches, we studied the changes in the bacterial, phage and fungal components of the microbiota as well as the metabolome and the ß-lactamase activity of the stools. This allowed assessing their degrees of perturbation and resilience. RESULTS: While only two subjects had detectable concentrations of antibiotics in their faeces, suggesting important antibiotic degradation in the gut, the intravenous treatment perturbed very significantly the bacterial and phage microbiota, as well as the composition of the metabolome. In contrast, treatment impact was relatively low on the fungal microbiota. At the end of the surveillance period, we found evidence of resilience across the gut system since most components returned to a state like the initial one, even if the structure of the bacterial microbiota changed and the dynamics of the different components over time were rarely correlated. The observed richness of the antibiotic resistance genes repertoire was significantly reduced up to day 30, while a significant increase in the relative abundance of ß-lactamase encoding genes was observed up to day 10, consistent with a concomitant increase in the ß-lactamase activity of the microbiota. The level of ß-lactamase activity at baseline was positively associated with the resilience of the metabolome content of the stools. CONCLUSIONS: In healthy adults, antibiotics perturb many components of the microbiota, which return close to the baseline state within 30 days. These data suggest an important role of endogenous ß-lactamase-producing anaerobes in protecting the functions of the microbiota by de-activating the antibiotics reaching the colon. Video Abstract.


Assuntos
Microbioma Gastrointestinal , Resiliência Psicológica , Adulto , Humanos , Microbioma Gastrointestinal/genética , beta-Lactamases/genética , beta-Lactamas/farmacologia , Voluntários Saudáveis , Antibacterianos , Bactérias/genética , Fezes/microbiologia
16.
Antimicrob Agents Chemother ; 57(3): 1488-95, 2013 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-23318796

RESUMO

Intestinal flora contains a reservoir of Gram-negative bacilli (GNB) resistant to cephalosporins, which are potentially pathogenic for intensive care unit (ICU) patients; this has led to increasing use of carbapenems. The emergence of carbapenem resistance is a major concern for ICUs. Therefore, in this study, we aimed to assess the intestinal carriage of imipenem-resistant GNB (IR-GNB) in intensive care patients. For 6 months, 523 consecutive ICU patients were screened for rectal IR-GNB colonization upon admission and weekly thereafter. The phenotypes and genotypes of all isolates were determined, and a case control study was performed to identify risk factors for colonization. The IR-GNB colonization rate increased regularly from 5.6% after 1 week to 58.6% after 6 weeks in the ICU. In all, 56 IR-GNB strains were collected from 50 patients: 36 Pseudomonas aeruginosa strains, 12 Stenotrophomonas maltophilia strains, 6 Enterobacteriaceae strains, and 2 Acinetobacter baumannii strains. In P. aeruginosa, imipenem resistance was due to chromosomally encoded resistance (32 strains) or carbapenemase production (4 strains). In the Enterobacteriaceae strains, resistance was due to AmpC cephalosporinase and/or extended-spectrum ß-lactamase production with porin loss. Genomic comparison showed that the strains were highly diverse, with 8 exceptions (4 VIM-2 carbapenemase-producing P. aeruginosa strains, 2 Klebsiella pneumoniae strains, and 2 S. maltophilia strains). The main risk factor for IR-GNB colonization was prior imipenem exposure. The odds ratio for colonization was already as high as 5.9 (95% confidence interval [95% CI], 1.5 to 25.7) after 1 to 3 days of exposure and increased to 7.8 (95% CI, 2.4 to 29.8) thereafter. In conclusion, even brief exposure to imipenem is a major risk factor for IR-GNB carriage.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/efeitos adversos , Enterobacteriaceae/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Imipenem/efeitos adversos , Pseudomonas aeruginosa/efeitos dos fármacos , Stenotrophomonas maltophilia/efeitos dos fármacos , Resistência beta-Lactâmica/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Acinetobacter baumannii/crescimento & desenvolvimento , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Técnicas de Tipagem Bacteriana , Estudos de Casos e Controles , Colo/microbiologia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/crescimento & desenvolvimento , Feminino , Expressão Gênica/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Imipenem/administração & dosagem , Unidades de Terapia Intensiva , Masculino , Pessoa de Meia-Idade , Pseudomonas aeruginosa/enzimologia , Pseudomonas aeruginosa/crescimento & desenvolvimento , Stenotrophomonas maltophilia/enzimologia , Stenotrophomonas maltophilia/crescimento & desenvolvimento , beta-Lactamases/genética , beta-Lactamases/metabolismo
17.
Antimicrob Agents Chemother ; 57(9): 4512-7, 2013 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-23836184

RESUMO

Extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli (ESBL E. coli) strains are of major concern because few antibiotics remain active against these bacteria. We investigated the association between the fecal relative abundance (RA) of ESBL-producing E. coli (ESBL-RA) and the occurrence of ESBL E. coli urinary tract infections (UTIs). The first stool samples passed after suspicion of UTI from 310 women with subsequently confirmed E. coli UTIs were sampled and tested for ESBL-RA by culture on selective agar. Predictive values of ESBL-RA for ESBL E. coli UTI were analyzed for women who were not exposed to antibiotics when the stool was passed. ESBL E. coli isolates were characterized for ESBL type, phylogroup, relatedness, and virulence factors. The prevalence of ESBL E. coli fecal carriage was 20.3%, with ESBL E. coli UTIs being present in 12.3% of the women. The mean ESBL-RA (95% confidence interval [CI]) was 13-fold higher in women exposed to antibiotics at the time of sampling than in those not exposed (14.3% [range, 5.6% to 36.9%] versus 1.1% [range, 0.32% to 3.6%], respectively; P < 0.001) and 18-fold higher in women with ESBL E. coli UTI than in those with another E. coli UTI (10.0% [range, 0.54% to 100%] versus 0.56% [range, 0.15% to 2.1%[, respectively; P < 0.05). An ESBL-RA of <0.1% was 100% predictive of a non-ESBL E. coli UTI. ESBL type, phylogroup, relatedness, and virulence factors were not found to be associated with ESBL-RA. In conclusion, ESBL-RA was linked to the occurrence of ESBL E. coli UTI in women who were not exposed to antibiotics and who had the same clone of E. coli in urine samples and fecal samples. Especially, a low ESBL-RA appeared to be associated with a low risk of ESBL E. coli infection.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/enzimologia , Fezes/microbiologia , Infecções Urinárias/microbiologia , Sistema Urinário/microbiologia , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Carga Bacteriana , Técnicas de Tipagem Bacteriana , Estudos Transversais , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Expressão Gênica , Humanos , Pessoa de Meia-Idade , Infecções Urinárias/tratamento farmacológico , Fatores de Virulência/metabolismo , beta-Lactamases/metabolismo
19.
J Travel Med ; 30(1)2023 02 18.
Artigo em Inglês | MEDLINE | ID: mdl-36444951

RESUMO

BACKGROUND: Colistin is an antibiotic of last resort in the management of highly drug-resistant Enterobacterales infections. Travel to some destinations presents a high risk of acquiring multidrug-resistant Enterobacterales, but little data are available on the risk of acquiring colistin-resistant strains. Here, we use the VOYAG-R sample collection (2012-2013) in order to evaluate the rate of acquisition of colistin-resistant Enterobacterales, excluding species with intrinsic resistance (CRE), following travel to tropical regions. METHODS: A total of 574 frozen stool samples of travellers returning from tropical regions were screened for colistin-resistant strains using ChromID Colistin R agar (bioMerieux®) after pre-enrichment culture with 1 mg/L of colistin. Genomes were obtained by Illumina sequencing and genetic determinants of colistin resistance (mutational events and mcr genes) were searched. RESULTS: A total of 22 travellers (3.8%) acquired colistin-resistant Enterobacterales carrying an mcr gene. Acquisition rates varied between visited regions: 9.2% (18/195) for Asia (southeast Asia: 17/18), 2.2% (4/184) for Latin America (Peru: 4/4) and 0% from Africa (0/195). Acquired strains were predominantly Escherichia coli (92%) and carried mostly the mcr-1 variant (83%). Escherichia coli strains belonged mainly to commensal phylogroups A and B1, and were genetically highly diverse (5 non-clonal sequence type (ST)10 and 17 ST singletons). Only four non mcr colistin-resistant strains (two E. coli and two Enterobacter cloacae complex) were identified. Among all the strains, two also carried extended-spectrum beta-lactamase genes. CONCLUSIONS: Travel to tropical regions, and particularly to Southeast Asia, is a risk factor for the acquisition of mcr-carrying Enterobacterales. This study highlights the community dissemination of mcr in humans as early as 2012, 4 years prior to its first published description.


Assuntos
Colistina , Proteínas de Escherichia coli , Humanos , Escherichia coli , Proteínas de Escherichia coli/genética , Farmacorresistência Bacteriana , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases
20.
Microorganisms ; 11(7)2023 Jul 09.
Artigo em Inglês | MEDLINE | ID: mdl-37512952

RESUMO

The physiopathological mechanisms responsible for digestive symptoms in COVID-19 patients are still unclear. The aim of this study was to determine the influence of faecal viral shedding on digestive symptoms and propose differential diagnoses in order to understand the gastrointestinal clinical spectrum in acute cases of COVID-19. All patients managed between March and May 2020, from whom stool samples were collected for microbiological investigations, were included. Microbiological analysis consisted of syndromic PCR screening and microscopic parasitological examination supplemented with microsporidia and multiplex protozoa PCR. SARS-CoV-2 infection was diagnosed via viral detection in respiratory and frozen stool samples, completed via serological test when necessary. Epidemiological, clinical, radiological, and biological data and clinical courses were compared according to COVID-19 status and faecal SARS-CoV-2 shedding and enteric co-infection status. The sample included 50 COVID+ and 67 COVID- patients. Faecal viral shedding was detected in 50% of stool samples and was associated with a higher viral load in the upper respiratory tract. Detected enteric pathogens were not different between subjects with different COVID-19 statuses or faecal SARS-CoV-2 shedding and had no impact on the clinical course for COVID-19 patients. The connection between SARS-CoV-2 shedding and enteric pathogen co-infection involvement in gastrointestinal presentation and clinical course is still unclear, suggesting other processes are involved in digestive disorders in COVID-19 patients.

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