PubMed Health⌕ Search

Biomedical subjects

Teresa M Coque

Publications and source records attributed to Teresa M Coque.

16 recordsLinked to original sources

The antimicrobial gut resistome of the Wayampi reveals a shared background of antibiotic and metal resistance genes with industrialized populations, underscoring the "robust-yet-fragile" architecture of human gut microbiomes.

BACKGROUND: Metagenomics enables detailed profiling of genes encoding antimicrobial resistance. However, most studies focus exclusively on antibiotic resistance genes (ARGs), excluding those associated with non-antibiotic antimicrobials (metals, biocides), and often rely on methods with low-sensitivity and low-specificity. Furthermore, they rarely examine populations exposed to minimal anthropogenic pollution. We analyzed fecal resistomes of 95 Wayampi individuals, an Indigenous community in remote French Guiana, using a targeted metagenomic capture platform covering 8667 genes, including ARGs, metal resistance genes (MRGs) and biocide resistance genes (BRGs) (PMID: 29335005). Resistome profiles were compared with those of Europeans to assess population-level differences. RESULTS: ARG richness was similar between groups (259 in Wayampi vs. 264 in Europeans, 159 shared), but MRGs&#x2009;+&#x2009;BRGs gene richness was significantly higher in Wayampi (11,930 vs. 7419). Most genes appeared in a minority of individuals (mean 5% for ARGs, 2% for MRGs&#x2009;+&#x2009;BRGs), but several ARGs for tetracyclines [tet(32), tet(40), tet(O), tet(Q), tet(W), tet(X), tetAB(P)], aminoglycosides (ant6'-I, aph3-III), macrolides (ermB, ermF, mefA), and sulfonamides (sul2) were present in all individuals. Tetracycline resistance genes predominated overall, while beta-lactam resistance genes were more common in Wayampi, and genes conferring resistance to aminoglycosides, amphenicols, and folate inhibitors were more frequent in Europeans. Among MRGs, copper and arsenic resistance genes prevailed in both groups, followed by those for zinc, iron, cobalt, and nickel. Up to 76% of Wayampiis carried acquired MRGs for copper (pcoABCDRS and tcrB), silver (silACFPRS), arsenic (ars), and mercury (mer) detoxification. Shannon diversity indices were similar for ARGs, MRGs, and BRGs, but composition and evenness differed significantly. UMAP and ADONIS analyses distinguished cohorts based on ARG profiles (p&#x2009;<&#x2009;0.001), but not on MRGs or BRGs. Correlation analysis revealed conserved gene-sharing networks and introgression of acquired ARGs and MRGs within both gut microbiomes. CONCLUSIONS: The diverse and balanced Wayampi resistome reflects a less perturbed microbiome compared to industrialized populations, and reveals a background of "core" and "shell" acquired ARGs and MRGs, consistent with the "robust-yet-fragile" architecture of scale-free networks. The patchy yet resilient gene distribution suggests varying levels of conserved gene sharing highways among populations, likely shaped by long-term microbial-human evolution, and supports a broader view on acquired antimicrobial resistance. Video Abstract.

Humans↗

Increased mutation frequencies in Escherichia coli isolates harboring extended-spectrum beta-lactamases.

Hypermutable (mutation frequency [f], > or = 4 x 10(-8)) Escherichia coli strains were more frequently found (43%) in a collection of 89 extended-spectrum beta-lactamase (ESBL)-producing isolates from different patients (77 pulsed-field gel electrophoresis clones, 12 ESBL types) than in non-ESBL E. coli (26%) strains (P = 0.03). Among urinary tract isolates, the frequency of hypermutation was 40% in ESBL versus 26% in non-ESBL isolates (P = 0.03).

Escherichia coli↗

CTX-M-10 linked to a phage-related element is widely disseminated among Enterobacteriaceae in a Spanish hospital.

CTX-M-10 has been widely disseminated among multiple clones of several species of Enterobacteriaceae, harboring seemingly different plasmids, for over a decade in Ramón y Cajal University Hospital, Madrid, Spain. Cloning and sequencing of a 12.2-kb DNA fragment from plasmid pRYCE21 from Klebsiella pneumoniae strain KP4aC revealed a novel phage-related element immediately upstream of bla(CTX-M-10) conserved among different CTX-M-10-producing strains. This is the first report showing an extended-spectrum-beta-lactamase gene linked to a phage-related element.

Amino Acid Sequence↗

Integron content of extended-spectrum-beta-lactamase-producing Escherichia coli strains over 12 years in a single hospital in Madrid, Spain.

The contribution of integrons to the dissemination of extended-spectrum beta-lactamases (ESBL) was analyzed on all ESBL-producing Escherichia coli isolates from 1988 to 2000 at Ramon y Cajal Hospital. We studied 133 E. coli pulsed-field gel electrophoresis types: (i) 52 ESBL-producing clinical strains (C-ESBL) (16 TEM, 9 SHV, 21 CTX-M-9, 1 CTX-M-14, and 5 CTX-M-10); (ii) 43 non-ESBL blood clinical strains (C-nESBL); and (iii) 38 non-ESBL fecal isolates from healthy volunteers (V-nESBL). Class 1 integrons were more common among C-ESBL (67%) than among C-nESBL (40%) or V-nESBL (26%) (P < 0.001) due to the high number of strains with bla(CTX-M-9), which is linked to an In6-like class 1 integron. Without this bias, class 1 integron occurrence would be similar in C-ESBL and C-nESBL groups (47% versus 40%). Occurrence of class 2 integrons was similar among clinical and community isolates (13 to 18%). No isolates contained class 3 integrons. The relatively low rate of class 1 integrons within transferable elements carrying bla(TEM) (23%) or bla(SHV) (33%) and the absence of class 2 integrons in all ESBL transconjugants mirror the assembly of translocative pieces containing bla(TEM) or bla(SHV) on local available transferable elements lacking integrons. The low diversity of class 1 integrons (seven types recovered in all groups) might indicate a wide dissemination of specific genetic elements in which they are located. In our environment, the spread of genetic elements encoding ESBL has no major impact on the dispersion of integrons, nor do integrons have a major impact on the spread of ESBL, except when bla(ESBL) genes are within an integron platform such as bla(CTX-M-9).

Cloning, Molecular↗

Population structure of Enterococcus faecium causing bacteremia in a Spanish university hospital: setting the scene for a future increase in vancomycin resistance?

Over an 8-year period (1995 to 2002), 86 Enterococcus faecium blood isolates from 84 patients, of which 54 were ampicillin resistant (AREF) and 32 were ampicillin susceptible (ASEF), were studied in a university hospital (1,200 beds; serving a population of 600,000) in Spain, a country characterized by a near-absence of resistance to vancomycin and very high rates of ampicillin resistance among enterococci. Clonal relatedness by pulsed-field gel electrophoresis (PFGE), antibiotic susceptibility, presence of the virulence/epidemicity genes esp(Efm) and hyl(Efm), and identification of purK alleles were studied. A group of isolates was also analyzed by amplified fragment length polymorphism (AFLP) and multilocus sequence typing. Medical charts (30 variables collected) were reviewed for 60/84 patients. ASEF showed high clonal diversity (32 PFGE types, 11 purK alleles, 4 AFLP genogroups), did not harbor putative virulence genes, and had no specific association with hospital acquisition. AREF isolates belonged to a clonal complex (CC) of genetically related strains (purK-1, AFLP genogroup C), occasionally harboring putative virulence traits, and were from patients with particular risk factors. Within this CC, previously associated with vancomycin-resistant E. faecium isolates causing outbreaks worldwide (W. L. Homan et al., J. Clin. Microbiol. 40:1963-1971, 2002), a great genetic diversity of antibiotic resistance and virulence/epidemicity profiles was found. Associations between esp and a >7-day hospital stay and between purK-1, hospital location, and nosocomial acquisition were noted (P < 0.001). These findings reflect the importance of local environmental differences in the evolution of this CC, suggesting that the emergence of vancomycin resistance among AREF strains in Spain may be a question of time.

Ampicillin↗

Molecular characterization of glycopeptide-resistant Enterococcus faecium isolates from Portuguese hospitals.

Fifty-one pulsed-field gel electrophoresis types and 17 Tn1546 variants were identified among 101 Enterococcus faecium isolates recovered in three distant Portuguese hospitals. Intra- and interhospital dissemination of specific strains and Tn1546 types was detected, which might largely contribute to the endemicity of vancomycin-resistant E. faecium in Portuguese hospitals, as happened previously in other geographical locations.

Anti-Bacterial Agents↗

Environmental contamination with vancomycin-resistant enterococci from hospital sewage in Portugal.

Vancomycin-resistant enterococci (VRE) were detected in samples of sewage obtained downstream of hospitals of the Porto area in Portugal, and in samples from the Douro Estuary. Clonal analysis, Tn1546 typing, and presence of putative virulence traits indicate the clinical origin of these isolates. This observation highlights the importance of hospital sewage in the VRE contamination of the environment.

Anti-Bacterial Agents↗

Global spread of vancomycin-resistant Enterococcus faecium from distinct nosocomial genetic complex.

Vancomycin-resistant enterococci (VRE) have caused hospital outbreaks worldwide, and the vancomycin-resistance gene (vanA) has crossed genus boundaries to methicillin-resistant Staphylococcus aureus. Spread of VRE, therefore, represents an immediate threat for patient care and creates a reservoir of mobile resistance genes for other, more virulent pathogens. Evolutionary genetics, population structure, and geographic distribution of 411 VRE and vancomycin-susceptible Enterococcus faecium isolates, recovered from human and nonhuman sources and community and hospital reservoirs in 5 continents, identified a genetic lineage of E. faecium (complex-17) that has spread globally. This lineage is characterized by 1) ampicillin resistance, 2) a pathogenicity island, and 3) an association with hospital outbreaks. Complex-17 is an example of cumulative evolutionary processes that improved the relative fitness of bacteria in hospital environments. Preventing further spread of this epidemic E. faecium subpopulation is critical, and efforts should focus on the early disclosure of ampicillin-resistant complex-17 strains.

Africa↗

Local genetic patterns within a vancomycin-resistant Enterococcus faecalis clone isolated in three hospitals in Portugal.

Eight pulsed-field gel electrophoresis subtypes and six Tn1546 variants were identified among Enterococcus faecalis isolates of a single clone recovered in three geographically separate Portuguese hospitals. Some clonal subtypes were found in particular hospitals, and Tn1546 variants were either widespread or confined to some of them. We also report on the first Tn1546 transposon containing an ISEf1 insertion.

Anti-Bacterial Agents↗

Dramatic increase in prevalence of fecal carriage of extended-spectrum beta-lactamase-producing Enterobacteriaceae during nonoutbreak situations in Spain.

The occurrence of extended-spectrum beta-lactamase (ESBL)-producing isolates has increased worldwide. Fecal carriage of ESBL-producing isolates has mainly been detected in nosocomial outbreaks, and few studies have evaluated fecal carriage during nonoutbreak situations and among patients in the community. We have studied the prevalence of ESBLs in 1,239 fecal samples from 849 patients (64.1% of whom were ambulatory) in 1991 and have compared the prevalence data with those obtained in 2003 for 400 fecal samples from 386 patients (75.9% of whom were ambulatory) and 108 samples from independent healthy volunteers. Samples were diluted in saline and cultured in two MacConkey agar plates supplemented with ceftazidime (1 microg/ml) and cefotaxime (1 microg/ml), respectively. Colonies were screened (by the double-disk synergy test) for ESBL production. The clonal relatedness of all ESBL-producing isolates was determined by pulsed-field gel electrophoresis with XbaI digestion; and the ESBLs of all ESBL-producing isolates were characterized by isoelectric focusing, PCR, and sequencing. The rates of fecal carriage of ESBL-producing isolates increased significantly (P < 0.001) in both hospitalized patients and outpatients, from 0.3 and 0.7%, respectively, in 1991, to 11.8 and 5.5%, respectively, in 2003. The rate of occurrence of ESBL-producing isolates among healthy volunteers was 3.7%. All ESBL-producing isolates recovered in 2003 were nonepidemic clones of Escherichia coli. ESBL characterization revealed an increasing diversity of ESBL types: TEM-4 and CTX-M-10 were the only enzymes detected in 1991, whereas TEM-4, TEM-52, SHV-12, CTX-M-9, CTX-M-10, CTX-M-14, and a CTX-M-2-like enzyme were recovered in 2003. The ESBL-producing isolates recovered from outpatients in 2003 corresponded to a CTX-M-9-type cluster (62.5%) and SHV-12 (31.2%), whereas TEM-4 was detected only in hospitalized patients. The frequencies of coresistance in isolates recovered in 2003 were as follows: sulfonamide, 75%; tetracycline, 64.3%; streptomycin, 57.1%; quinolones, 53.5%; and trimethoprim, 50%. The increased prevalence of fecal carriage of ESBL-producing isolates during nonoutbreak situations in hospitalized patients and the establishment of these isolates in the community with coresistance to non-beta-lactam antibiotics, including quinolones, represent an opportunity for these isolates to become endemic.

Electrophoresis, Gel, Pulsed-Field↗

Multi-resistant Gram-negative bacilli: from epidemics to endemics.

PURPOSE OF REVIEW: Infections due to multi-drug resistant Gram-negative bacilli represent a worrying situation for the management of hospitalized patients. In addition, these bacteria are increasingly involved in epidemics throughout the world. This review focuses on recent data that may help to understand the emergence and dissemination of multi-drug resistant bacilli and the current trend from epidemic to endemic situations. RECENT FINDINGS: Well-established clones enhance their resistance phenotype by the acquisition of new resistant genes, via gene capture genetic units (plasmids, transposons or integrons), thus facilitating the co-selective process under different antimicrobial selective pressures and therefore the long-term persistence of organisms in selective environments. Not only resistant bacterial clones are selected, but also their genetic structures carrying resistance genes. Therefore, current epidemiology of multi-drug resistant bacilli is not only focused on bacterial clones but also on any kind of resistance gene capture units. In this scenario a multiclonal population structure of bacterial organisms corresponds to a collection of different strains sharing resistance genes carried by horizontally transferred genetic structures. As different strains tend to prefer different environments, this concept helps understand why the epidemiology of multi-drug resistant Gram-negative bacilli is moving from epidemics to endemics. SUMMARY: The emergence and spread of multi-drug resistant bacilli in the nosocomial setting should be understood in terms of a complex interplay of bacterial clonality, resistance genes and genetic structures promoting rapid dissemination of antimicrobial resistance. Intervention strategies in the forthcoming scenario should identify existing epidemic and/or endemic situations involving clonal organisms or resistance genes carried by epidemic gene capture units.

Cross Infection↗

Allodemics.

Explore the source record for details and available documents.

Bacteria↗

Risk factors associated with ampicillin resistance in patients with bacteraemia caused by Enterococcus faecium.

Epidemiological characteristics of ampicillin-resistant, vancomycin-susceptible Enterococcus faecium are not well known. Recently, these strains have been proposed as the substratum for the later appearance of vancomycin-resistant E. faecium. To analyse this problem, the medical charts of patients with bacteraemia caused by E. faecium diagnosed in our institution during a 6 year period (1994-1999) were reviewed. Demographic data, clinical characteristics, antibiotic exposure and outcome were compared among patients with ampicillin-resistant (MIC > 16 mg/L, NCCLS criteria) and ampicillin-susceptible strains. Clonality between different strains was analysed by pulsed-field gel electrophoresis (PFGE). We evaluated 49 cases of E. faecium bacteraemia; 29 patients with ampicillin-resistant strains and 20 patients with -susceptible strains were identified. By logistic regression analysis, only previous administration of beta-lactams (OR: 6.3; 95% CI: 1.12-20.0) and urinary catheterization (OR:4.2; 95% CI: 1.3-30.0) were identified as predictors of ampicillin resistance in enterococcal bacteraemic patients. An elevated APACHE II score was the only independent factor associated with mortality in enterococcal bacteraemia (OR:13.5; 95% CI: 1.04-175.4). PFGE analysis revealed a strong association between specific ampicillin-resistant clones and the location of patients during hospitalization, suggesting nosocomial transmission. Bacteraemia caused by ampicillin-resistant enterococci was not associated with increased mortality when compared with bacteraemias caused by ampicillin-susceptible strains.

Ampicillin Resistance↗

High occurrence of esp among ampicillin-resistant and vancomycin-susceptible Enterococcus faecium clones from hospitalized patients.

The ability to colonize patients successfully may be essential for the emergence and spread of resistant nosocomial strains. We determined the presence of Esp, a surface protein involved in colonization ability in Enterococcus faecalis, in 96 Enterococcus faecium isolates from hospitalized patients (77 PFGE clones), 33 faecal isolates from healthy volunteers (32 clones) and 20 environmental isolates (20 clones). Esp was found significantly more often in E. faecium isolated from hospitalized patients than in isolates from the community setting (26% versus 6%, P < 0.01) and was significantly more common among ampicillin-resistant than among ampicillin-susceptible strains (37% versus 4%, P < 0.001), regardless of the isolation site. The frequency of the esp gene in the hospital clearly correlates with antibiotic-resistant E. faecium clones. This observation indicates that antibiotic-resistant variants may frequently arise under antibiotic selective pressure among esp-positive clones reaching ecological abundance in the nosocomial habitat.

Ampicillin Resistance↗

Genes encoding TEM-4, SHV-2, and CTX-M-10 extended-spectrum beta-lactamases are carried by multiple Klebsiella pneumoniae clones in a single hospital (Madrid, 1989 to 2000).

Over a 12-year period (1989 to 2000), 159 Klebsiella pneumoniae isolates harboring extended-spectrum beta-lactamases (ESBLs) (4.8% of the total number of K. pneumoniae isolates obtained) were recovered from 58 patients, who were mainly hospitalized in intensive care and surgery units. For 62 representative isolates from 58 patients, 31 clonal types harboring TEM-4 (n = 5), SHV-2 (n = 7), SHV2a (n = 4), SHV-5 (n = 1), CTX-M-10 (n = 13), or CTX-M-9 (n = 1) beta-lactamases were identified by pulsed-field gel electrophoresis. This is the first report to document the presence of the CTX-M-10 or the CTX-M-9 beta-lactamase in K. pneumoniae. These beta-lactamases were previously identified in Escherichia coli isolates from Spain. Only two of five K. pneumoniae TEM-4 clones caused more than a single case of infection, with one of them spreading for 9 months. A single plasmid was detected among these TEM-4 clones. Only two of seven K. pneumoniae clones containing SHV-2 and three of four strains harboring SHV-2a were detected in more than one case of infection. Plasmids encoding SHV-2 or SHV-2a were unrelated. Four of 13 K. pneumoniae CTX-M-10 clones were found in more than one patient, with two of them recovered 2 and 5 years apart. As in the case of the SHV-2 isolates, we were unable to document a common transmissible genetic element that could explain the polyclonal structure of our isolates. Nevertheless, the spread of a single gene may be suggested by the presence of a conserved set of noncoding polymorphisms in the sequences. Most ESBL-producing K. pneumoniae clones were ephemeral, being poorly selected and maintained in the hospital setting, but the genes encoding ESBL persisted successfully over the years that the strains were recovered, probably as a minority gene population in the hospital metagenome.

DNA, Bacterial↗

Epidemiology of extended-spectrum beta-lactamase-producing Enterobacter isolates in a Spanish hospital during a 12-year period.

Fifteen Enterobacter clinical isolates (11 Enterobacter cloacae isolates, 3 Enterobacter aerogenes isolates, and 1 Enterobacter gergoviae isolate), representing 0.4% of all Enterobacter isolates recovered in our hospital from 1989 to 2000, were suspected of harboring an extended-spectrum beta-lactamase (ESBL). These isolates were recovered from 14 different patients. ESBLs were transferred by conjugation into an Escherichia coli recipient strain. Pulsed-field gel electrophoresis (PFGE) revealed a single clone of E. aerogenes and six different clones of E. cloacae. Four of these E. cloacae clonal types were represented by only one isolate each, but the other two were represented by three and four isolates, respectively. Isoelectric focusing, susceptibility phenotyping, PCR analysis, and sequencing demonstrated the presence of three different ESBLs. The most frequent was the recently characterized CTX-M-10 ESBL, which was found in the E. gergoviae isolate and in all but one of the E. cloacae isolates. The remaining E. cloacae isolate harbored a TEM-27 ESBL, and the three E. aerogenes isolates harbored a TEM-24 ESBL. PFGE revealed that our E. aerogenes strain was indistinguishable from the French TEM-24-producing E. aerogenes endemic clone. Although a low prevalence of ESBL-producing Enterobacter isolates was found in our institution over a 12-year period, a diversity of nonepidemic E. cloacae clones was detected, as was the persistence of the CTX-M-10 beta-lactamase. The presence of the TEM-24-producing E. aerogenes French clone in our institution also demonstrates the intercountry dissemination of ESBL-producing isolates.

Bacterial Proteins↗