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1.
Int J Antimicrob Agents ; 55(3): 105887, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31926283

RESUMO

The STEP surveillance study was designed to increase knowledge about distribution of multidrug-resistant (MDR) Enterobacterales and Pseudomonas aeruginosa in Portugal, focusing on the intensive care unit (ICU). Antimicrobial susceptibility of common agents was also evaluated and compared with that of one of the latest therapeutic introductions, ceftolozane-tazobactam (C/T). Clinical isolates of Enterobacterales (n=426) and P. aeruginosa (n=396) from patients admitted in Portuguese ICUs were included. Activity of C/T and comparators was investigated using standard broth microdilution. Isolates were recovered from urinary tract (UTI, 36.9%), intra-abdominal (IAI, 24.2%) and lower respiratory tract (LRTI, 38.9%) infections. In P. aeruginosa, overall distribution of MDR/extremely-drug resistant (XDR)/pan-drug resistant (PDR) isolates accounted for 21.2%, 23.2% and 0.8%, respectively. C/T was the most potent agent tested against P. aeruginosa and MDR/XDR/PDR phenotypes. In Escherichia coli, extended-spectrum beta-lactamases (ESBL) and carbapenemase (CP) phenotypes accounted for 16.6% and 1.7%, respectively, whereas in Klebsiella spp., ESBL and CP-phenotypes represented 28.5% and 17.9%, respectively. Overall, susceptibility of C/T against Enterobacterales was 86.9%. C/T was the least affected agent in E. coli (99.4% susceptibility), whereas its activity was moderate in Klebsiella spp. (71.5%) and Enterobacter spp. (70.4%), due in part to a high rate of ESBL and CP-phenotypes. In Enterobacterales, blaKPC was the most prevalent CP gene (63.0%), followed by blaOXA-48 (33.3%) and blaVIM (3.7%). These microbiological results reinforce C/T as a therapeutic option in ICU patients with UTI, IAI or LRTI due to P. aeruginosa or Enterobacterales isolates, but not for CP producers.


Assuntos
Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Infecções Intra-Abdominais/tratamento farmacológico , Infecções por Pseudomonas/tratamento farmacológico , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções Respiratórias/tratamento farmacológico , Tazobactam/farmacologia , Infecções Urinárias/tratamento farmacológico , Antibacterianos/uso terapêutico , Cefalosporinas/uso terapêutico , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , Humanos , Unidades de Terapia Intensiva , Portugal , Infecções por Pseudomonas/microbiologia , Tazobactam/uso terapêutico
2.
Int J Antimicrob Agents ; 55(3): 105905, 2020 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-31991221

RESUMO

BACKGROUND: Limited treatment options complicate management of infections with New Delhi metallo-ß-lactamase (NDM)-producing organisms. The efficacy of combination therapy with meropenem (MEM) and cefmetazole (CMZ) was assessed against NDM-producing Enterobacteriaceae. MATERIALS AND METHODS: Twelve Escherichia coli clinical isolates harbouring blaNDM-1 and a positive control E. coli BAA-2469 harbouring blaNDM-1 were studied. Minimum inhibitory concentrations (MICs) of MEM, ertapenem (ERT) and CMZ were determined by broth microdilution. Checkerboard and time-kill assays were performed to confirm the in vitro efficacy of the MEM/CMZ combination. Scanning electron microscopy, kinetic studies and whole-genome sequence analysis were used to determine the antimicrobial resistance mechanisms. RESULTS: MICs of MEM, ERT and CMZ in monotherapy ranged from 8 to 32, 16 to 128, and 32 to 512 µg/mL, respectively. In the checkerboard assay, MEM/ERT resulted in no synergy, whereas MEM/CMZ showed a synergistic effect in all the tested isolates. Furthermore, the MIC of MEM in combination decreased by 2- to 8-fold compared with that of MEM alone. The time-kill study revealed a bactericidal effect in 4 of 13 isolates at 24 h. Scanning electron microscopy showed spheroidisation of the bacterial cell in the MEM/CMZ combination; this was not observed in single antibiotic conditions. Kinetic studies indicated CMZ was a better antagonist for NDM-1 than ERT. Whole-genome sequence analysis did not reveal any explainable differences between isolates susceptible and those non-susceptible to combination therapy. CONCLUSION: In vitro studies showed the potential effectiveness of MEM/CMZ combination therapy against NDM-producing organisms.


Assuntos
Antibacterianos/farmacologia , Cefmetazol/farmacologia , Infecções por Enterobacteriaceae/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Meropeném/farmacologia , Antibacterianos/uso terapêutico , Cefmetazol/uso terapêutico , Quimioterapia Combinada , Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Ertapenem/farmacologia , Humanos , Meropeném/uso terapêutico , beta-Lactamases/biossíntese
3.
J Med Microbiol ; 69(2): 228-232, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31922949

RESUMO

Introduction. Rapid and reliable detection of carbapenemase-producing Enterobacterales (CPE) from surveillance cultures is critical in supporting a good infection control programme. We implemented a new algorithm for CPE detection incorporating the NG Test CARBA 5 in January 2019.Aim. Our goals were to compare turnaround time (TAT), costs and staff requirements between the old and new algorithm, and to evaluate the performance of the CARBA 5 test directly on colonies grown on CARBA Smart agar.Methodology. We analysed and compared the TAT of CPE surveillance cultures processed using the old and new CPE screening algorithm. The total actual reagent costs and staff requirements for the new CPE algorithm were compared with the estimated costs and staff requirements of the old CPE algorithm.Results. Of 197 isolates included in the evaluation of the new algorithm, 64 were positive for carbapenemases by both CARBA 5 and Xpert Carba-R assay. Of the 133 that were negative, two were found to harbour NDM and IMI genotypes. Significant improvements in TAT were achieved with 88.7 % of cultures with CPE, reported on the same day as growth was observed on CARBA Smart agar compared to none in the old algorithm. The new algorithm incurred lower costs and, based on our workload, the new algorithm is estimated to save 28.9 man-hours annually.Conclusion. CARBA 5 performs well on colonies growing on CARBA Smart agar and significant improvements in TAT can be achieved without incurring additional costs or staff requirements.


Assuntos
Proteínas de Bactérias/metabolismo , Técnicas de Laboratório Clínico/métodos , Contagem de Colônia Microbiana/métodos , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/crescimento & desenvolvimento , Enterobacteriaceae/isolamento & purificação , Ensaios Enzimáticos/métodos , Algoritmos , Proteínas de Bactérias/genética , Técnicas de Laboratório Clínico/economia , Contagem de Colônia Microbiana/economia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/diagnóstico , Ensaios Enzimáticos/economia , Humanos , Sensibilidade e Especificidade , beta-Lactamases/genética , beta-Lactamases/metabolismo
4.
J Med Microbiol ; 69(2): 233-238, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31971501

RESUMO

Introduction. Raoultella spp. representatives are Gram-negative rod-shaped bacteria of the Enterobacteriaceae family. These bacteria are commonly found in the natural environment.Aim. The aim of the study was to indicate the reliable method for Raoultella spp. strains identification, evaluate the susceptibility of Raoultella spp. strains to selected antimicrobials and to detect their resistance mechanisms to beta-lactams.Methodology. Susceptibility of the strains to chosen antimicrobials was determined using the automatic method. The presence of particular antimicrobial resistant mechanism and genes encoding ESBLs and MBLs was determined respectively with double-disc synergy test and commercially available kit - eazyplex SuperBug CRE test (Amplex Diagnostics) and standard PCR. For the selected strains, DNA sequencing was performed.Results. Amongst 105 of the examined Raoultella spp. strains, majority were sensitive to: imipenem (99.0 %), meropenem (98.1 %), gentamicin (93.3 %) and ciprofloxacin (92.4 %). Of the tested Raoultella strains, thirteen (12.4 %) produced ESBLs and one strain simultaneously ESBLs and MBLs. The DNA sequencing results were as follows: for all the reference strains the correct species identification was achieved, for the analysed strains two were identified as R. planticola and one as R. ornithinolytica.Conclusion. Although Raoultella spp. strains remain sensitive to antibiotics, there is a constant need to monitor the sensitivity of these bacteria to selected antimicrobials. Isolation of a multi-drug resistant R. ornithinolytica strain indicates that even the less frequently isolated species of Enterobacteriaceae family should be precisely identified because they might be of clinical importance and the particular strain can also produce enzymes that pose the greatest threat today.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Humanos , Imipenem/farmacologia , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo , beta-Lactamas/farmacologia
5.
J Med Microbiol ; 69(2): 207-217, 2020 Feb.
Artigo em Inglês | MEDLINE | ID: mdl-31976856

RESUMO

Introduction. Infections attributable to carbapenem-resistant Gram-negative bacilli are increasing globally. New antimicrobial agents are urgently needed to treat patients with these infections.Aim. To describe susceptibility to the novel carbapenem-ß-lactamase inhibitor combination imipenem-relebactam and comparators of clinical isolates of non-Proteeae Enterobacteriaceae (NPE) and Pseudomonas aeruginosa from intraabdominal infections (IAIs) and urinary tract infections (UTIs).Methods. Broth microdilution MICs were determined for isolates collected in 22 European countries in 2015-2017 and interpreted using EUCAST breakpoints; imipenem-relebactam MICs were interpreted using imipenem breakpoints.Results. For NPE, 98.4 % of isolates from IAIs (n=10,465) and 98.5 % of UTI isolates (n=7,446) were susceptible to imipenem-relebactam, as were 42.4 % of imipenem-nonsusceptible (n=474), 98.6 % of Klebsiella pneumoniae carbapenemase (KPC)-positive (n=138), and 93.9 % of multidrug-resistant (MDR) isolates (n=4,424) from IAIs and UTIs combined. Molecular analysis demonstrated that two-thirds of imipenem-nonsusceptible isolates rendered susceptible by relebactam carried KPCs; 96 % (261/271) of imipenem-nonsusceptible isolates of NPE that remained nonsusceptible in the presence of relebactam carried metallo-ß-lactamase (MBL)-type and/or OXA-48-like carbapenemases. Among P. aeruginosa, 94.4 % of IAI (n=1,245) and 93.0 % of UTI isolates (n=714) were susceptible to imipenem-relebactam, as were 74.4 % of imipenem-nonsusceptible (n=469) and 79.8 % of MDR isolates (n=595) from IAIs and UTIs combined. Among the 120 isolates of P. aeruginosa that remained nonsusceptible to imipenem upon addition of relebactam, 72 % carried MBLs. The distribution of NPE and P. aeruginosa carrying carbapenemases varied substantially across Europe, as did resistance to imipenem and imipenem-relebactam.Conclusions. Continued surveillance of antimicrobial resistance and resistance mechanisms, including the study of imipenem-relebactam as it approaches regulatory approval, appears warranted.


Assuntos
Antibacterianos/farmacologia , Compostos Azabicíclicos/farmacologia , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Imipenem/farmacologia , Infecções Intra-Abdominais/microbiologia , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções Urinárias/microbiologia , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/fisiologia , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Monitoramento Epidemiológico , Europa (Continente)/epidemiologia , Humanos , Infecções Intra-Abdominais/epidemiologia , Testes de Sensibilidade Microbiana , Infecções por Pseudomonas/epidemiologia , Infecções por Pseudomonas/microbiologia , Pseudomonas aeruginosa/isolamento & purificação , Pseudomonas aeruginosa/fisiologia , Infecções Urinárias/epidemiologia
7.
Lett Appl Microbiol ; 70(1): 21-28, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31630429

RESUMO

Morganella morganii is an opportunistic bacterial pathogen of the Enterobacteriaceae family that is occasionally isolated from clinical (animal and human) specimens with varying resistance profiles. Detailed genomic analyses of drug-resistant M. morganii strains are relatively limited, particularly in Africa, which is also due to their relatively low isolation rates from clinical settings. Here we report on two multidrug-resistant clinical M. morganii isolates from urine specimens of two hospitalized patients in South Africa who presented with urinary tract infections in 2013. The isolates, M006 and E042, were only susceptible to carbapenems, amikacin and tigecycline. One strain, M006, had a novel class 1 integron, ln1484, associated with aadA7, sul1and gcuD gene cassettes and a Col3M plasmid replicase gene. The ln1484 intI1:aadA7:sul1 genes were bracketed by a TnAs3 composite transposon while a tet(B) gene was found on an IS4 family transposon. The rare blaDHA-4 and blaDHA-1 AmpC ß-lactamase genes were identified on the isolates' chromosome. The isolates were phylogenetically distant and closely related to other international strains, suggesting that they were not obtained from a single epidemiological source. Further molecular surveillance is necessary to establish the prevalence of these MDR strains in the tertiary hospital. Moreover antibiotic stewardship and antibiotic sensitivity testing of all clinical isolates should be undertaken after empirical treatment to inform tailored therapy as well as reduce escalation of resistance and associated morbidities and mortalities. SIGNIFICANCE AND IMPACT OF THE STUDY: We report on the first clinical Morganella morganii draft genomes from Africa. The isolates were found in the urine of patients presenting with urinary tract infections (UTIs). Notably, they were resistant to important clinical antibiotics, including those used to treat UTIs. Due to the common occurrence of UTIs, particularly among pregnant women for whom drug options are limited, the presence of antibiotic-resistant uropathogens such as M. morganii is a serious public health concern. We therefore characterized the resistance mechanisms and epidemiology of these isolates to provide further insights into their dissemination and background data for future studies.


Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae/microbiologia , Morganella morganii/genética , Morganella morganii/isolamento & purificação , Infecções Urinárias/microbiologia , Idoso de 80 Anos ou mais , Amicacina/farmacologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Feminino , Genoma Bacteriano , Genômica , Humanos , Integrons , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Morganella morganii/classificação , Morganella morganii/efeitos dos fármacos , Filogenia , Plasmídeos/genética , Plasmídeos/metabolismo , África do Sul , beta-Lactamases/genética , beta-Lactamases/metabolismo
8.
Lett Appl Microbiol ; 70(1): 42-47, 2020 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-31642085

RESUMO

The increasing frequency of class A KPC enzymes, class B metallo-ß-lactamases (MBLs) and class D OXA-48 enzymes in Enterobacteriaceae makes their early identification urgent. A simple commercial MASTDISCS combi Carba plus disc system (MAST-Carba plus) was designed for the identification of MBLs, KPC and OXA-48 carbapenemase genes in Enterobacteriaceae. To validate the MAST-Carba plus, a total of 77 isolates of carbapenemase-producing Enterobacteriaceae (CPE) and 84 isolates of noncarbapenemase-producing Enterobacteriaceae (non-CPE) were selected for differentiation of the genes of Enterobacteriaceae by MAST-Carba plus. Meanwhile, the carbapenemase genes such as blaKPC , blaIMP , blaVIM , blaNDM-1 and blaOXA-48 were detected by PCR (polymerase chain reaction). Thus, when considered on the basis of PCR results, the sensitivity of MAST-Carba plus detection of KPC strains is 82·3%, the specificity is 100·0%, the positive predictive value is 100·0% and the negative predictive value is 92·4%. For MBLs strains, the sensitivity is 100·0%, the specificity is 97·1%, the positive predictive value is 84·6% and the negative predictive value is 100·0%. For OXA-48 strains, the sensitivity is 100·0%, the specificity is 99·4%, the positive predictive value is 80·0% and the negative predictive value is 100·0%. Our findings suggest that MAST-Carba plus is a rapid and promising method for identifying the MBLs, KPC and OXA-48 carbapenemase genes in Enterobacteriaceae, which could be exploited in basic microbiology laboratory to prevent the transmission of CPE. SIGNIFICANCE AND IMPACT OF THE STUDY: Not only detection of carbapenemases but also identification of their genes accurately and rapidly in Enterobacteriaceae is still a major challenge for clinical laboratories in order to prevent the transmission of carbapenemase-producing Enterobacteriaceae (CPE). Therefore, this study aimed to evaluate the performance of a new rapid method (MASTDISCS combi Carba plus) for the identification of metallo-ß-lactamases (MBLs), KPC and OXA-48 carbapenemase genes in Enterobacteriaceae clinical isolates.


Assuntos
Proteínas de Bactérias/análise , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , Enterobacteriaceae/isolamento & purificação , Ensaios Enzimáticos/métodos , beta-Lactamases/análise , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Sensibilidade e Especificidade , beta-Lactamases/genética , beta-Lactamases/metabolismo
9.
Bratisl Lek Listy ; 120(12): 935-940, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31855054

RESUMO

OBJECTIVES: We focused on detecting the most frequent resistance mechanisms in selected multidrug-resistant (MDR) strains and determining their antimicrobial resistance. BACKGROUND: MDR pathogens pose urgent public health threat due to limited treatment options, rigorous control measures and significant mortality. METHODS: We confirmed extended-spectrum ß-lactamase (ESBL) and carbapenemase producing Enterobacteriaceae through guidelines, as well following ß-lactamases: AmpC by cloxacillin, class A carbapenemase with phenylboronic acid, class B metallo-ß-lactamase with ethylenediaminetetraacetic acid. Multilocus sequence typing was used to investigate 20 Escherichia coli strains. RESULTS: Overall 205 mostly ESBL Escherichia coli demonstrated resistance against amikacin (4.7 %), tigecycline (1.2 %), and no resistance to ceftazidime/avibactam, meropenem, nitrofurantoin and fosfomycin. Out of 41 Klebsiella species (spp.), 37 (90.2 %) showed carbapenemase activity, 13 (35.1 %) of class A and 24 (64.9 %) of class B. Resistance was following: meropenem 66.7 %, tigecyclin 10.2 % and colistin 0 %. From Enterobacter spp. 21 strains, 14 (66.7 %) were ESBL, 5 produced ESBL and/or AmpC and 2 were MDR. We ascertained 14 (70 %) E. coli sequence type - ST131. CONCLUSIONS: The study revealed various resistance mechanisms in concert with different agents and association of specific ST131 within E. coli. These characteristics considerably contribute to emergence of antimicrobial resistance (Tab. 4, Ref. 30).


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Klebsiella pneumoniae/efeitos dos fármacos , beta-Lactamases/metabolismo , Adulto , Idoso , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/enzimologia , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Farmacorresistência Bacteriana , Enterobacteriaceae/classificação , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , beta-Lactamases/genética
10.
Rev Chilena Infectol ; 36(4): 433-441, 2019 Aug.
Artigo em Espanhol | MEDLINE | ID: mdl-31859766

RESUMO

BACKGROUND: Infections caused by extended-spectrum beta-lactamases enterobacteria (ESBL-EP) have implications for neonatal morbidity and mortality. AIM: To describe the prevalence of ESBL-EP in neonatal sepsis and associated factors. METHODS: A prospective cohort study was conducted from August 2016 to August 2017; newborn babies (NB) hospitalized in the Hospital Civil de Guadalajara "Dr. Juan I. Menchaca" were included. The ESBL-EP were investigated by double-disk synergy test and its association with clinical and demographic characteristics of the NB. RESULTS: A total of 1,501 hospitalized NB were studied, with an average gestational age of 36.3 weeks. They were diagnosed 196 neonatal sepsis events, the most frequent etiologies were enterobacteria (45.5%). Resistance to ampicilin was found in 88.8% and to broad spectrum cephalosporins in more than 42% of the strains; 22.9% of them were ESBL phenotype. Apgar ≤ 7 at five minutes of life (OR 4.6; 95% CI 1.47-14.6) and gestational age < 37 weeks (OR 5.4; 95% CI 1.04-27.) increase the risk. CONCLUSION: In enterobacteria that cause neonatal sepsis, 22.9% were EP-ESBL; infection was more likely in patients with Apgar ≤ 7 at five minutes of age and in preterm infants.


Assuntos
Antibacterianos/farmacologia , Infecção Hospitalar/microbiologia , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Sepse Neonatal/microbiologia , beta-Lactamases/biossíntese , Adolescente , Adulto , Criança , Enterobacteriaceae/classificação , Feminino , Humanos , Recém-Nascido , Unidades de Terapia Intensiva Neonatal , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência , Estudos Prospectivos , Fatores de Risco , Adulto Jovem
11.
BMC Infect Dis ; 19(1): 979, 2019 Nov 21.
Artigo em Inglês | MEDLINE | ID: mdl-31752702

RESUMO

BACKGROUND: Fluoroquinolones are commonly recommended as treatment for urinary tract infections (UTIs). The development of resistance to these agents, particularly in gram-negative microorganisms complicates treatment of infections caused by these organisms. This study aimed to investigate antimicrobial resistance of different Enterobacteriaceae species isolated from hospital- acquired and community-acquired UTIs against fluoroquinolones and correlate its levels with the existing genetic mechanisms of resistance. METHODS: A total of 440 Enterobacteriaceae isolates recovered from UTIs were tested for antimicrobial susceptibility. Plasmid-mediated quinolone resistance (PMQR) genes and mutations in the quinolone resistance-determining regions (QRDRs) of gyrA and parC genes were examined in quinolone-resistant strains. RESULTS: About (32.5%) of isolates were resistant to quinolones and (20.5%) were resistant to fluoroquinolones. All isolates with high and intermediate resistance phenotypes harbored one or more PMQR genes. QnrB was the most frequent gene (62.9%) of resistant isolates. Co-carriage of 2 PMQR genes was detected in isolates (46.9%) with high resistance to ciprofloxacin (CIP) (MICs > 128 µg/mL), while co-carriage of 3 PMQR genes was detected in (6.3%) of resistant isolates (MICs > 512 µg/mL). Carriage of one gene only was detected in intermediate resistance isolates (MICs of CIP = 1.5-2 µg/mL). Neither qnrA nor qnrC genes were detected. The mutation at code 83 of gyrA was the most frequent followed by Ser80-Ile in parC gene, while Asp-87 Asn mutation of gyrA gene was the least, where it was detected only in high resistant E. coli isolates (MIC ≥128 µg/mL). A double mutation in gyrA (Lys154Arg and Ser171Ala) was observed in high FQs resistant isolates (MIC of CIP < 128 µg/mL). CONCLUSION: FQs resistance is caused by interact between PMQR genes and mutations in both gyrA and parC genes while a mutation in one gene only can explain quinolone resistance. Accumulation of PMQR genes and QRDR mutations confers high resistance to FQs.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/genética , Quinolonas/farmacologia , Infecções Urinárias/microbiologia , Adulto , Proteínas de Bactérias/metabolismo , Ciprofloxacino/farmacologia , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Feminino , Fluoroquinolonas/farmacologia , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Mutação , Plasmídeos/genética , Plasmídeos/metabolismo , Adulto Jovem
12.
Medicine (Baltimore) ; 98(39): e17339, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31574872

RESUMO

INTRODUCTION: During the past decade, the rate of carbapenem resistance among Enterobacteriaceae, mostly in Escherichia coli and Klebsiella pneumoniae, has significantly increased worldwide. It is a great challenge for the choice of drug treatment especially in children.Tigecycline is the first drug in the glycylcycline class of antibiotics. For children, the China Food and Drug Administration and US Food and Drug Administration postulated that tigecycline is not recommended. It must be used only as salvage therapy for life-threatening infections in critically ill children who have no alternative treatment options. PATIENT CONCERNS: A male pediatric case of 4.5 months was blood stream infection after liver transplantation. The blood cultures obtained grew Gram-negative rods, which reportedly grew a strain of extended-spectrum ß-lactamase and carbapenemases-producing Escherichia coli within 10 hours. All bacterial isolates were found to be resistant to all antimicrobial agents except aminoglycosides and tigecycline. DIAGNOSES: Complicated intra-abdominal infection, central line-associated blood stream infection. INTERVENTIONS: The blood stream infection with carbapenem-resistant Escherichia coli after liver transplantation was cured by tigecycline. OUTCOMES: The patient's condition continued to improve, then transferred to general ward. CONCLUSION: The following report, to our knowledge, is the youngest liver transplantation patient who used tigecycline treatment around the world. It provides reference and experience for the use of tigecycline in infants with severe infections.


Assuntos
Antibacterianos/uso terapêutico , Enterobacteriáceas Resistentes a Carbapenêmicos , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Escherichia coli/tratamento farmacológico , Complicações Pós-Operatórias/tratamento farmacológico , Tigeciclina/uso terapêutico , Infecções por Enterobacteriaceae/microbiologia , Infecções por Escherichia coli/microbiologia , Humanos , Lactente , Transplante de Fígado/efeitos adversos , Masculino , Complicações Pós-Operatórias/microbiologia
13.
Microbiol Res ; 229: 126325, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31563838

RESUMO

Edwardsiella bacteria cause economic losses to a variety of commercially important fish globally. Human infections are rare and result in a gastroenteritis-like illness. Because these bacteria are evolutionarily related to other Enterobacteriaceae and the host cytoskeleton is a common target of enterics, we hypothesized that Edwardsiella may cause similar phenotypes. Here we use HeLa and Caco-2 infection models to show that microtubules are severed during the late infections. This microtubule alteration phenotype was not dependant on the type III or type VI secretion system (T3SS and T6SS) of the bacteria as ΔT3SS and ΔT6SS mutants of E. piscicida EIB202 and E. tarda ATCC15947 that lacks both also caused microtubule disassembly. Immunolocalization experiments showed the host katanin catalytic subunits A1 and A like 1 proteins at regions of microtubule severing, suggesting their involvement in the microtubule disassembly events. To identify bacterial components involved in this phenotype, we screened a 2,758 transposon library of E. piscicida EIB202 and found that 4 single mutations in the atpFHAGDC operon disrupted microtubule disassembly in HeLa cells. We then constructed three atp deletion mutants; they all could not disassemble host microtubules. This work provides the first clear evidence of host cytoskeletal alterations during Edwardsiella infections.


Assuntos
Edwardsiella/fisiologia , Infecções por Enterobacteriaceae/veterinária , Células Epiteliais/metabolismo , Doenças dos Peixes/metabolismo , Microtúbulos/metabolismo , Animais , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Células CACO-2 , Edwardsiella/genética , Infecções por Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Células Epiteliais/microbiologia , Doenças dos Peixes/microbiologia , Regulação Bacteriana da Expressão Gênica , Células HeLa , Interações Hospedeiro-Patógeno , Humanos , Óperon , Sistemas de Secreção Tipo III/genética , Sistemas de Secreção Tipo III/metabolismo , Sistemas de Secreção Tipo VI/genética , Sistemas de Secreção Tipo VI/metabolismo
14.
mSphere ; 4(5)2019 09 11.
Artigo em Inglês | MEDLINE | ID: mdl-31511372

RESUMO

An Enterobacter hormaechei isolate harboring bla VIM-4 and mcr-9 was recovered from a pediatric patient in a U.S. hospital. The bla VIM-4 and mcr-9 genes are carried on the same IncH12 plasmid, pME-1a. The isolate tested susceptible to colistin, without observed induction of colistin resistance. The mcr-9 gene is located between two insertion elements, IS903 and IS1, but lacks the downstream regulatory genes (qseC and qseB) found in other isolates that harbor mcr-9 IMPORTANCE We describe the complete genome assembly and sequence of a clinical Enterobacter isolate harboring both bla VIM-4 and mcr-9 recovered from a pediatric patient in the United States with a history of travel to Egypt. Moreover, to the best of our knowledge, this is the first report of an Enterobacter isolate harboring both bla VIM-4 and mcr-9 from the United States. The bla VIM-4 and mcr-9 genes are carried on the same IncH12 plasmid, pME-1a. The isolate tested susceptible to colistin, without observed induction of colistin resistance. The mcr-9 gene is located between two insertion elements, IS903 and IS1, but lacks the downstream regulatory genes (qseC and qseB) found in other isolates that harbor mcr-9.


Assuntos
Enterobacter/genética , Enterobacter/isolamento & purificação , Genoma Bacteriano , beta-Lactamases/genética , Pré-Escolar , Egito , Enterobacter/enzimologia , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/microbiologia , Humanos , Masculino , Plasmídeos/genética , Análise de Sequência de DNA , Doença Relacionada a Viagens , Estados Unidos
15.
Environ Pollut ; 255(Pt 1): 113143, 2019 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-31541827

RESUMO

Environmental reservoirs of antibiotic resistance (AR) are a growing concern that are gathering more attention as potential sources for human infection. Carbapenem-resistant Enterobacteriaceae (CRE) are extremely dangerous, as carbapenems are often drugs of last resort that are used to treat multi-drug resistant infections. Among the genes capable of conferring carbapenem resistance to bacteria, the most transferrable are those that produce carbapenemase, an enzyme that hydrolyzes carbapenems and other ß-lactam antibiotics. The goal of this review was to comprehensively identify global environmental reservoirs of carbapenemase-producing genes, as well as identify potential routes of transmission to humans. The genes of interest were Klebsiella pneumoniae carbapenemase (KPC), New Delhi Metallo-ß-lactamase (NDM), Oxacillinase-48-type carbapenemases (OXA-48), and Verona Integron-Mediated Metallo-ß-lactamase (VIM). Carbapenemase genes have been reported in the environment on almost every continent. Hospital and municipal wastewater, drinking water, natural waterways, sediments, recreational waters, companion animals, wildlife, agricultural environments, food animals, and retail food products were identified as current reservoirs of carbapenemase-producing bacteria and genes. Humans have been recorded as carrying CRE, without recent admittance to a hospital or long-term care facility in France, Egypt, and China. CRE infections from the environment have been reported in patients in Montpellier, France and Cairo, Egypt. This review demonstrates the need for 1) comprehensive monitoring of AR not only in waterways, but also other types of environmental matrices, such as aerosol, dusts, periphyton, and surfaces in indoor environments; and 2) action to reduce the prevalence and mitigate the effects of these potentially deadly resistance genes. In order to develop an accurate quantitative model for environmental dimensions of AR, longitudinal sampling and quantification of AR genes and bacteria are needed, using a One Health approach.


Assuntos
Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , beta-Lactamases/genética , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/transmissão , Genes Bacterianos , Saúde Global , Humanos
16.
Ann Agric Environ Med ; 26(3): 405-408, 2019 Sep 19.
Artigo em Inglês | MEDLINE | ID: mdl-31559794

RESUMO

INTRODUCTION: Carbapenemase-producing Enterobacteriaceae have spread rapidly through the countries and continents to become a global concern. One of the main reservoirs of NDM-1 positive strains from the Enterobacteriaceae family is the Indian subcontinent (Bangladesh, Pakistan, India). MATERIAL AND METHODS: During June 2017 - June 2018, rectal swab samples were collected routinely in all patients returning to Poland from South and South-East Asia. During molecular examinations gene blaNDM-1 encoding NDM-1 carbapenemase was detected. RESULTS: 31 patients were examined after returning to Poland from a trip to South and South-East Asia. The presence of New Delhi Metallo-ß-lactamase-1 producing Escherichia coli and Klebsiella pneumoniae was confirmed in three patients (9.7%) returning to Poland from travels to India. All the positive patients were hospitalized during the trip in a New Delhi hospital. CONCLUSIONS: Digestive tract carriage of NDM in a group of Polish travelers is a significant health and epidemiological problem. The study confirms the necessity for screening for carbapenemase-producing Enterobacteriaceae (CPE), particularly among travellers. Rectal swabs should be collected in every case of patients returning from international trips, and the possibility of environment-associated infections should be emphasized.


Assuntos
Proteínas de Bactérias/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/enzimologia , Klebsiella pneumoniae/enzimologia , Viagem , beta-Lactamases/metabolismo , Adulto , Proteínas de Bactérias/genética , Escherichia coli/genética , Escherichia coli/isolamento & purificação , Feminino , Humanos , Índia , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Polônia , beta-Lactamases/genética
17.
BMJ Case Rep ; 12(9)2019 Sep 05.
Artigo em Inglês | MEDLINE | ID: mdl-31492731

RESUMO

A 72-year-old gentleman with significant cardiac history and a pacemaker in situ initially presented to the emergency department 5 days after he had his pacemaker-unit batteries changed. He had deranged vital signs, productive cough and fever. His chest plain radiograph did not show evidence of infection; however, he had right basal crackles on auscultation, which suggested a lower respiratory tract infection. He was treated with intravenous co-amoxiclav and supportive therapy, which led to his improvement. The patient was discharged but had to be readmitted a total of four times over the span of 4 months due to recurrent fever and associated symptoms. Transthoracic and transoesophageal echocardiograms and CT of the neck/thorax/abdomen/pelvis were done to look for endocarditis, pacemaker-unit infection and other sources of infection. However, these did not show any evidence of infection. He did have persistent raised inflammatory markers and two blood cultures growing Enterobacter cloacae. A fluorodeoxyglucose positron emission tomography scan was done, which showed evidence of pacemaker lead infection. His pacemaker unit was removed, which led to cessation of his symptoms and normalisation of his inflammatory markers. He had no further hospital admissions to date and has been regularly followed up in an outpatient cardiology clinic.


Assuntos
Infecções por Enterobacteriaceae/diagnóstico , Marca-Passo Artificial , Infecções Relacionadas à Prótese/diagnóstico , Idoso , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/uso terapêutico , Hemocultura , Remoção de Dispositivo , Enterobacter cloacae/isolamento & purificação , Infecções por Enterobacteriaceae/complicações , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/terapia , Febre de Causa Desconhecida/etiologia , Fluordesoxiglucose F18 , Hospitalização , Humanos , Masculino , Readmissão do Paciente , Tomografia por Emissão de Pósitrons , Infecções Relacionadas à Prótese/complicações , Infecções Relacionadas à Prótese/microbiologia , Infecções Relacionadas à Prótese/terapia , Compostos Radiofarmacêuticos
18.
BMC Infect Dis ; 19(1): 678, 2019 Aug 01.
Artigo em Inglês | MEDLINE | ID: mdl-31370804

RESUMO

BACKGROUND: Fecal colonization with carbapenem-resistant Enterobacteriaceae (CRE) is a risk factor for bacterial translocation resulting in subsequent endogenous infections. The purpose of this study is to investigate the prevalence of CRE strains colonization in stool samples of outpatient in a tertiary pediatric hospital of Shanghai, China. METHODS: In a retrospective study, fecal samples were consecutively obtained from patients in 2016 and screening test for CRE was conducted by using home-made MacConkey agar. Antimicrobial susceptibility was determined by the broth microdilution method and ß-lactamases were characterized by polymerase chain reaction (PCR) assays and DNA sequencing. Multilocus sequence typing (MLST) was performed for the genetic relationships of the isolates. RESULTS: A total of 880 fecal samples were included for this screening test and 32 CRE strains were identified in 32 non-duplicate fecal samples from 32 children (1.3 ± 1.5 years), with a carriage rate of 3.6%. These strains mainly distributed in Klebsiella pnuemoniae (37.5%) and Escherichia coli (37.5%). All CRE strains showed high resistance to most of the routinely used antibiotics (> 90%) except for polymyxin B and tigecycline. The blaNDM gene was the major carbapenemase gene harbored by gastrointestinal CRE strains, followed by blaKPC-2, blaIMP-26, and blaIMP-4. Other ß-Lactamase genes including blaCTX-M, blaSHV, blaTEM-1, and blaDHA-1 were also detected. MLST analysis revealed that various sequence types (STs) were detected in these strains, with ST11 and ST37 being more prevalent in K.pneumoniae and ST101 in E.coli. CONCLUSIONS: This study revealed the prevalence of CRE fecal carriage in children from outpatient and urgent implementation of infection control measure should be conducted to limit the spread of CRE strains.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/patogenicidade , Infecções por Enterobacteriaceae/epidemiologia , Fezes/microbiologia , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Pré-Escolar , China/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/genética , Feminino , Humanos , Lactente , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Masculino , Testes de Sensibilidade Microbiana , Epidemiologia Molecular , Tipagem de Sequências Multilocus , Pacientes Ambulatoriais/estatística & dados numéricos , Prevalência , Estudos Retrospectivos , beta-Lactamases/genética
19.
Eur J Clin Microbiol Infect Dis ; 38(11): 2029-2036, 2019 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-31385145

RESUMO

Carbapenemase-producing microorganisms are increasingly isolated and often associated with treatment failures and outbreaks. The need for reliable and timely detection and/or confirmation of carbapenemase production is paramount; therefore, a real-time PCR assay targeting IMP, NDM, VIM, KPC and OXA-48-like carbapenemases was designed and validated. All available allele variants of the above carbapenemases were downloaded from the Beta-Lactamase DataBase ( http://bldb.eu/ ), aligned with Clustal Omega and primers designed using Primer-BLAST. Real-time PCR monoplexes were optimized for the QuantStudio 6-Flex (Applied Biosystems) using the PowerUp SYBR Green Master Mix (Life Technologies) and validated using a panel of 204 characterised strains carrying a wide range of beta-lactamases, sometimes in combination. Melt-curve analysis was used to confirm positive results. The in silico approach allowed primers to be designed in conserved regions of the KPC and NDM alignments, while three primer sets for IMP and two for VIM were necessary to ensure amplification of the different variants. One primer set was designed for OXA-48-like; however, it is unlikely to detect all variants. Expected results were obtained for all 204 tested strains, with 100% sensitivity and specificity. Melt-curve analysis showed consistent Tm results for KPC, NDM, and OXA-48-like; differences were instead noted for IMP and VIM as likely consequence of higher variability in the PCR target regions. Inhibition was not observed. The assay is rapid, easy to perform and implement. It enables unequivocal detection of IMP, NDM, VIM, KPC and OXA-48-like carbapenemases even when more than one type is present simultaneously.


Assuntos
Proteínas de Bactérias/genética , Técnicas Bacteriológicas/métodos , Bactérias Gram-Negativas/enzimologia , Bactérias Gram-Negativas/isolamento & purificação , Infecções por Bactérias Gram-Negativas/diagnóstico , Reação em Cadeia da Polimerase em Tempo Real , beta-Lactamases/genética , Testes Diagnósticos de Rotina , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/diagnóstico , Infecções por Enterobacteriaceae/microbiologia , Bactérias Gram-Negativas/genética , Infecções por Bactérias Gram-Negativas/microbiologia , Humanos , Sensibilidade e Especificidade
20.
Clin Microbiol Rev ; 32(4)2019 09 18.
Artigo em Inglês | MEDLINE | ID: mdl-31413045

RESUMO

While the description of resistance to quinolones is almost as old as these antimicrobial agents themselves, transferable mechanisms of quinolone resistance (TMQR) remained absent from the scenario for more than 36 years, appearing first as sporadic events and afterward as epidemics. In 1998, the first TMQR was soundly described, that is, QnrA. The presence of QnrA was almost anecdotal for years, but in the middle of the first decade of the 21st century, there was an explosion of TMQR descriptions, which definitively changed the epidemiology of quinolone resistance. Currently, 3 different clinically relevant mechanisms of quinolone resistance are encoded within mobile elements: (i) target protection, which is mediated by 7 different families of Qnr (QnrA, QnrB, QnrC, QnrD, QnrE, QnrS, and QnrVC), which overall account for more than 100 recognized alleles; (ii) antibiotic efflux, which is mediated by 2 main transferable efflux pumps (QepA and OqxAB), which together account for more than 30 alleles, and a series of other efflux pumps (e.g., QacBIII), which at present have been sporadically described; and (iii) antibiotic modification, which is mediated by the enzymes AAC(6')Ib-cr, from which different alleles have been claimed, as well as CrpP, a newly described phosphorylase.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana/genética , Infecções por Enterobacteriaceae/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Quinolonas/farmacologia , Proteínas de Escherichia coli/genética , Humanos
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