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1.
Front Microbiol ; 15: 1439373, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-39086650

RESUMO

Introduction: Acinetobacter baumannii contributes significantly to the global issue of multidrug-resistant (MDR) nosocomial infections. Often, these strains demonstrate resistance to carbapenems (MDR-CRAB), the first-line treatment for infections instigated by MDR A. baumannii. Our study focused on the antimicrobial susceptibility and genomic sequences related to plasmids from 12 clinical isolates of A. baumannii that carry both the blaOXA-58 and bla NDM-1 carbapenemase genes. Methods: Whole-genome sequencing with long-read technology was employed for the characterization of an A. baumannii plasmid that harbors the bla OXA-58 and blaNDM-1 genes. The location of the bla OXA-58 and bla NDM-1 genes was confirmed through Southern blot hybridization assays. Antimicrobial susceptibility tests were conducted, and molecular characterization was performed using PCR and PFGE. Results: Multilocus Sequence Typing analysis revealed considerable genetic diversity among bla OXA-58 and bla NDM-1 positive strains in Brazil. It was confirmed that these genes were located on a plasmid larger than 300 kb in isolates from the same hospital, which also carry other antimicrobial resistance genes. Different genetic contexts were observed for the co-occurrence of these carbapenemase-encoding genes in Brazilian strains. Discussion: The propagation of bla OXA-58 and bla NDM-1 genes on the same plasmid, which also carries other resistance determinants, could potentially lead to the emergence of bacterial strains resistant to multiple classes of antimicrobials. Therefore, the characterization of these strains is of paramount importance for monitoring resistance evolution, curbing their rapid global dissemination, averting outbreaks, and optimizing therapy.

2.
Appl Environ Microbiol ; 90(8): e0116524, 2024 08 21.
Artigo em Inglês | MEDLINE | ID: mdl-39012101

RESUMO

Antibiotic resistance has emerged as a global threat to public health, generating a growing interest in investigating the presence of antibiotic-resistant bacteria in environments influenced by anthropogenic activities. Wastewater treatment plants in hospital serve as significant reservoirs of antimicrobial-resistant bacteria, where a favorable environment is established, promoting the proliferation and transfer of resistance genes among different bacterial species. In our study, we isolated a total of 243 strains from 5 hospital wastewater sites in Mexico, belonging to 21 distinct Gram-negative bacterial species. The presence of ß-lactamase was detected in 46.9% (114/243) of the isolates, which belonging to the Enterobacteriaceae family. We identified a total of 169 ß-lactamase genes; blaTEM in 33.1%, blaCTX-M in 25.4%, blaKPC in 25.4%, blaNDM 8.8%, blaSHV in 5.3%, and blaOXA-48 in 1.1% distributed in 12 different bacteria species. Among the 114 of the isolates, 50.8% were found to harbor at least one carbapenemase and were discharged into the environment. The carbapenemase blaKPC was found in six Citrobacter spp. and E. coli, while blaNDM was detected in two distinct Enterobacter spp. and E. coli. Notably, blaNDM-1 was identified in a 110 Kb IncFII conjugative plasmid in E. cloacae, E. xiangfangensis, and E. coli within the same hospital wastewater. In conclusion, hospital wastewater showed the presence of Enterobacteriaceae carrying a high frequency of carbapenemase blaKPC and blaNDM. We propose that hospital wastewater serves as reservoirs for resistance mechanism within bacterial communities and creates an optimal environment for the exchange of this resistance mechanism among different bacterial strains. IMPORTANCE: The significance of this study lies in its findings regarding the prevalence and diversity of antibiotic-resistant bacteria and genes identified in hospital wastewater in Mexico. The research underscores the urgent need for enhanced surveillance and prevention strategies to tackle the escalating challenge of antibiotic resistance, particularly evident through the elevated frequencies of carbapenemase genes such as blaKPC and blaNDM within the Enterobacteriaceae family. Moreover, the identification of these resistance genes on conjugative plasmids highlights the potential for widespread transmission via horizontal gene transfer. Understanding the mechanisms of antibiotic resistance in hospital wastewater is crucial for developing targeted interventions aimed at reducing transmission, thereby safeguarding public health and preserving the efficacy of antimicrobial therapies.


Assuntos
Proteínas de Bactérias , Citrobacter , Enterobacter , Hospitais , Águas Residuárias , beta-Lactamases , Águas Residuárias/microbiologia , beta-Lactamases/genética , Proteínas de Bactérias/genética , Citrobacter/genética , Citrobacter/enzimologia , Citrobacter/efeitos dos fármacos , Citrobacter/isolamento & purificação , Enterobacter/genética , Enterobacter/efeitos dos fármacos , Enterobacter/isolamento & purificação , Enterobacter/enzimologia , Antibacterianos/farmacologia , México
3.
J Microbiol Methods ; 223: 106972, 2024 08.
Artigo em Inglês | MEDLINE | ID: mdl-38871227

RESUMO

Recently, considerable uncertainty has arisen concerning the appropriate susceptibility testing for cefiderocol in gram-negative bacilli, particularly in the context of its application to Acinetobacter spp. The optimal method for assessing the susceptibility levels of Acinetobacter spp. to cefiderocol remains a subject of debate due to substantial disparities observed in the values obtained through various testing procedures. This study employed four minimum inhibitory concentration (MIC) methodologies and the disk diffusion to assess the susceptibility of twenty-seven carbapenem resistant (CR)-Acinetobacter strains to cefiderocol. The results from our study reveal significant variations in the minimum inhibitory concentration (MIC) values obtained with the different methods and in the level of agreement in interpretation categories between the different MIC methods and the disk diffusion test. Among the MIC methods, there was relatively more consistency in reporting the interpretation categories. For European Committee on Antimicrobial Susceptibility Testing (EUCAST) breakpoints, the categorical agreement (CA) for MIC methods ranged between 66.7 and 81.5%. On the other hand, the essential agreement (EA) values were as low as 18.5-29.6%. The CA between MIC methods and disk diffusion was 81.5%. These results emphasize the need for a reliable, accurate, and clinically validated methodology to effectively assess the susceptibility of Acinetobacter spp. to cefiderocol. The wide variability observed in our study highlights the importance of standardizing the susceptibility testing process for cefiderocol to ensure consistent and reliable results for clinical decision-making.


Assuntos
Acinetobacter , Antibacterianos , Cefiderocol , Cefalosporinas , Testes de Sensibilidade Microbiana , Testes de Sensibilidade Microbiana/métodos , Acinetobacter/efeitos dos fármacos , Antibacterianos/farmacologia , Cefalosporinas/farmacologia , Humanos , Infecções por Acinetobacter/microbiologia
4.
BMC Vet Res ; 20(1): 174, 2024 May 03.
Artigo em Inglês | MEDLINE | ID: mdl-38702700

RESUMO

Antimicrobial resistance is considered one of the most critical threat for both human and animal health. Recently, reports of infection or colonization by carbapenemase-producing Enterobacterales in companion animals had been described. This study report the first molecular characterization of NDM-producing Enterobacterales causing infections in companion animals from Argentina. Nineteen out of 3662 Enterobacterales isolates analyzed between October 2021 and July 2022 were resistant to carbapenemes by VITEK2C and disk diffusion method, and suspected to be carbapenemase-producers. Ten isolates were recovered from canine and nine from feline animals. Isolates were identified as K. pneumoniae (n = 9), E. coli (n = 6) and E. cloacae complex (n = 4), and all of them presented positive synergy among EDTA and carbapenems disks, mCIM/eCIM indicative of metallo-carbapenemase production and were also positive by PCR for blaNDM gene. NDM variants were determined by Sanger sequencing method. All 19 isolates were resistant to ß-lactams and aminoglycosides but remained susceptible to colistin (100%), tigecycline (95%), fosfomycin (84%), nitrofurantoin (63%), minocycline (58%), chloramphenicol (42%), doxycycline (21%), enrofloxacin (5%), ciprofloxacin (5%) and trimethoprim/sulfamethoxazole (5%). Almost all isolates (17/19) co-harbored blaCTX-M plus blaCMY, one harbored blaCTX-M alone and the remaining blaCMY. E. coli and E. cloacae complex isolates harbored blaCTX-M-1/15 or blaCTX-M-2 groups, while all K. pneumoniae harbored only blaCTX-M-1/15 genes. All E. coli and E. cloacae complex isolates harbored blaNDM-1, while in K. pneumoniae blaNDM-1 (n = 6), blaNDM-5 (n = 2), and blaNDM-1 plus blaNDM-5 (n = 1) were confirmed. MLST analysis revealed the following sequence types by species, K. pneumoniae: ST15 (n = 5), ST273 (n = 2), ST11, and ST29; E. coli: ST162 (n = 3), ST457, ST224, and ST1196; E. cloacae complex: ST171, ST286, ST544 and ST61. To the best of our knowledge, this is the first description of NDM-producing E. cloacae complex isolates recovered from cats. Even though different species and clones were observed, it is remarkable the finding of some major clones among K. pneumoniae and E. coli, as well as the circulation of NDM as the main carbapenemase. Surveillance in companion pets is needed to detect the spread of carbapenem-resistant Enterobacterales and to alert about the dissemination of these pathogens among pets and humans.


Assuntos
Antibacterianos , Doenças do Gato , Doenças do Cão , Infecções por Enterobacteriaceae , beta-Lactamases , Animais , Gatos , Cães , Doenças do Gato/microbiologia , Doenças do Gato/epidemiologia , beta-Lactamases/genética , Argentina/epidemiologia , Infecções por Enterobacteriaceae/veterinária , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/epidemiologia , Antibacterianos/farmacologia , Doenças do Cão/microbiologia , Doenças do Cão/epidemiologia , Testes de Sensibilidade Microbiana , Animais de Estimação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/genética , Enterobacteriaceae/enzimologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/enzimologia
5.
Int Microbiol ; 2024 Apr 30.
Artigo em Inglês | MEDLINE | ID: mdl-38691195

RESUMO

In 2014, Brazil detected New Delhi metallo-ß-lactamase (NDM)-producing Enterobacterales from a Providencia rettgeri isolate obtained through surveillance swabs in the Southern region. Subsequently, various species have reported several NDM enzymes. However, comprehensive data on the current epidemiology of NDM-producing P. rettgeri in Brazil remains limited. This study, aimed to provide a detailed characterization of the phenotypic, genotypic, and epidemiological profile of clinical isolates of P. rettgeri NDM. From April 2020 to December 2022, 18 carbapenem-resistant P. rettgeri strains, previously identified using Vitek2®, were isolated at the University Hospital of Londrina. Resistance and virulence genes were assessed through genetic analysis using ERIC PCR and NextSeq (Illumina) sequencing. Statistical analysis was conducted using SPSS version 2.0. Genomic analysis confirmed the presence of ß-lactamase blaNDM-1 and blaOXA-1. All isolates showed the presence of the NDM encoding gene and genetic similarity above 90% between isolates. Clinical parameters of patients infected with P. rettgeri exhibited significant association with mechanical ventilation, prior use of carbapenems, and polymyxins. We also report a significant association between P. rettgeri infection and death outcome. This study characterizes NDM-1 metallo-ß-lactmases isolates, among P. rettgeri isolates from patients at the University Hospital (HU), during the COVID-19 pandemic. The emergence of this novel resistance mechanism among P. rettgeri poses a significant challenge, limiting the therapeutic options for infections in our hospital.

6.
J Glob Antimicrob Resist ; 37: 176-178, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38583573

RESUMO

OBJECTIVES: To describe at genomic level nine carbapenemase-producing Klebsiella pneumoniae ST307 (Kp-ST307) clinical isolates recovered in Buenos Aires during 2017 to 2021, investigating their resistome, virulome, and phylogeny. METHODS: Antimicrobial susceptibility was determined according to Clinical and Laboratory Standards Intitute (CLSI). Genomic DNA was sequenced by Illumina MiSeq and analysed using SPAdes, PROKKA, and Kleborate. Phylogeny of 355 randomly selected Kp-ST307 genomes and those from nine local isolates was inferred by a maximum-likelihood approach. The tree was visualized using Microreact. RESULTS: Besides resistance to ß-lactams and fluoroquinolones, six out of nine Kp-ST307 were also resistant to ceftazidime/avibactam (CZA). This difficult-to-treat resvistance phenotype was mediated by blaSHV-28 and GyrA-83I/ParC-80I mutations in addition to carbapenemase coding genes. Among CZA susceptible isolates, two of them harboured blaKPC-3 while the other harboured blaKPC-2+blaCTX-M-15. Regarding CZA-resistant isolates, three harboured blaKPC-3+blaNDM-1+blaCMY-6, two carried blaKPC-2+blaNDM-5+blaCTX-M-15, and blaNDM-5+blaCTX-M-15 were detected in the remaining isolate. Furthermore, five colistin-resistant isolates presented a nonsense mutation in mgrB. Global Kp-ST307 isolates were distributed in two deep-branching lineages while local isolates were set in the main clade of the phylogenetic tree. The five isolates from the same hospital, harbouring blaKPC-3 or blaKPC-3+blaNDM-1+blaCMY-6, clustered in a monophyletic subclade with Italian isolates. Also, an isolate harbouring blaKPC-2+blaNDM-5+blaCTX-M-15 recovered in another hospital was closed to this group. The remaining local Kp-ST307 were grouped in other subclades containing isolates of diverse geographical origin. CONCLUSION: The inferred resistome was consistent with the resistant phenotype. Phylogeny suggested multiple introduction events in our region and a single major introduction in one hospital followed by local spread.


Assuntos
Antibacterianos , Proteínas de Bactérias , Ceftazidima , Infecções por Klebsiella , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Filogenia , beta-Lactamases , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/classificação , Argentina , beta-Lactamases/genética , Proteínas de Bactérias/genética , Humanos , Infecções por Klebsiella/microbiologia , Antibacterianos/farmacologia , Ceftazidima/farmacologia , Farmacorresistência Bacteriana Múltipla/genética , Genoma Bacteriano , Compostos Azabicíclicos/farmacologia , Combinação de Medicamentos , Genômica , Sequenciamento Completo do Genoma
7.
Braz J Microbiol ; 55(2): 1437-1443, 2024 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-38499916

RESUMO

Carbapenem-resistant Klebsiella pneumoniae (CRKP) exhibit high mortality rates in pediatric patients and usually belong to international high-risk clones. This study aimed to investigate the molecular epidemiology and carbapenem resistance mechanisms of K. pneumoniae isolates recovered from pediatric patients, and correlate them with phenotypical data. Twenty-five CRKP isolates were identified, and antimicrobial susceptibility was assessed using broth microdilution. Carbapenemase production and ß-lactamase genes were detected by phenotypic and genotypic tests. Multilocus sequence typing was performed to differentiate the strains and whole-genome sequencing was assessed to characterize a new sequence type. Admission to the intensive care unit and the use of catheters were significantly positive correlates of CRKP infection, and the mortality rate was 36%. Almost all isolates showed multidrug-resistant phenotype, and most frequent resistant gene was blaKPC. We observed the dissemination of ST307 and clones belonging to CG258, which are considered high risk. In pediatric patients, these clones present with high genomic plasticity, favoring adaptation of the KPC and NDM enzymes to healthcare environments.


Assuntos
Antibacterianos , Carbapenêmicos , Infecções por Klebsiella , Klebsiella pneumoniae , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , beta-Lactamases , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Klebsiella pneumoniae/classificação , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/epidemiologia , Brasil , Criança , Antibacterianos/farmacologia , beta-Lactamases/genética , beta-Lactamases/metabolismo , Carbapenêmicos/farmacologia , Pré-Escolar , Lactente , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/classificação , Masculino , Feminino , Proteínas de Bactérias/genética , Sequenciamento Completo do Genoma , Adolescente , Genótipo , Epidemiologia Molecular , Farmacorresistência Bacteriana Múltipla/genética
8.
Diagn Microbiol Infect Dis ; 109(1): 116246, 2024 May.
Artigo em Inglês | MEDLINE | ID: mdl-38452556

RESUMO

Providencia rettgeri, belonging to the genus Providencia, had gained significant interest due to its increasing prevalence as a common pathogen responsible for healthcare-associated infections in hospitals. P. rettgeri isolates producing carbapenemases have been reported to reduce the efficiency of carbapenems in clinical antimicrobial therapy. However, coexistence with other resistance determinants is rarely reported. The goal of this study was the molecular characterization of carbapenemase-producing Providencia spp. clinical isolates. Among 23 Providencia spp. resistant to imipenem, 21 were positive to blaNDM-1; one positive to blaNDM-1 and blaOXA-58 like; and one isolate co-producing blaIMP-27, blaOXA-24/40 like, and blaOXA-58 like were identified. We observed a low clonal relationship, and the incompatibility groups Col3M and ColRNAI were identified in the plasmid harboring blaNDM-1. We report for the first time a P. rettgeri strain co-producing blaIMP-27, blaOXA-24-like, and blaOXA-58 like. The analysis of these resistance mechanisms in carbapenemase co-producing clinical isolates reflects the increased resistance.


Assuntos
Antibacterianos , Providencia , Humanos , Antibacterianos/farmacologia , Providencia/genética , México/epidemiologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Proteínas de Bactérias/genética
9.
Microbiol Immunol ; 68(1): 1-5, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-37859304

RESUMO

Over the last decade, New Delhi metallo-beta-lactamase (NDM) carbapenemase has silently spread in Brazil. In this study, we analyzed a large collection of Enterobacterales other than Klebsiella spp. received in our reference laboratory between 2013 and 2022. A total of 32 clinical isolates displaying different pulsed-field gel electrophoresis profiles, and represented by 11 species in the families Enterobacteriaceae (Citrobacter freundii, Citrobacter portucalensis, Enterobacter hormaechei, and Escherichia coli), Morganellaceae (Morganella morganii, Proteus mirabilis, Proteus vulgaris, Providencia rettgeri, Providencia stuartii, and Raoultella ornithinolytica), and Yersiniaceae (Serratia marcescens) had their whole genomes sequenced and further analyzed. Antimicrobial susceptibility was determined by disk diffusion, except for polymyxin B, assessed by broth microdilution. The blaNDM-1 allele was predominant (n = 29), but blaNDM-5 was identified in an E. coli specimen with a novel ST, and the blaNDM-7 allele was found in E. hormaechei ST45 and E. coli ST1049. Polymyxin was active against all but one Enterobacteriaceae isolate: an mcr-1-producing E. coli presenting minimal inhibitory concentration (4 mg/L). Isolates producing extended-spectrum ß-lactamases were common: cefotaximase from Munich (CTX-M)-15 (n = 10), CTX-M-2 (n = 4), and CTX-M-8 (n = 3) were detected, and the mcr-1-producing E. coli was found to co-produce both CTX-M-8 and CTX-M-55 ß-lactamases. The mcr-9 gene was found in 5/8 E. hormaechei isolates, distributed in four different sequence types, all of them presenting susceptibility to polymyxin. This study showed that NDM-producing Enterobacterales other than Klebsiella are already spread in Brazil, in diversified species, and cocarrying important resistance genes. Prompt detection and effective implementation of measures to prevent further spread are mandatory for mitigating the dissemination of NDM carbapenemase in hospital settings and preserving the already limited antimicrobial therapy options.


Assuntos
Infecções por Enterobacteriaceae , Escherichia coli , Humanos , Klebsiella/genética , Brasil/epidemiologia , Antibacterianos/farmacologia , beta-Lactamases/genética , Infecções por Enterobacteriaceae/epidemiologia , Genômica , Testes de Sensibilidade Microbiana , Polimixinas/farmacologia
10.
Antimicrob Agents Chemother ; 68(2): e0116823, 2024 Feb 07.
Artigo em Inglês | MEDLINE | ID: mdl-38063400

RESUMO

The design of inhibitors against metallo-ß-lactamases (MBLs), the largest family of carbapenemases, has been a strategic goal in designing novel antimicrobial therapies. In this regard, the development of bicyclic boronates, such as taniborbactam (TAN) and xeruborbactam, is a major achievement that may help in overcoming the threat of MBL-producing and carbapenem-resistant Gram-negative pathogens. Of concern, a recent report has shown that New Delhi MBL-9 (NDM-9) escapes the inhibitory action of TAN by a single amino acid substitution with respect to New Delhi MBL-1 (NDM-1), the most widely disseminated MBL. Here, we report a docking and computational analysis that identifies that "escape variants" against TAN can arise by disruption of the electrostatic interaction of negative charges in the active site loops of MBLs with the N-(2-aminoethyl)cyclohexylamine side chain of TAN. These changes result in non-productive binding modes of TAN that preclude reaction with the MBLs, a phenomenon that is not restricted to NDM-9. This analysis demonstrates that single amino acid substitutions in non-essential residues in MBL loops can unexpectedly elicit resistance to TAN.


Assuntos
Antibacterianos , Ácidos Borínicos , Ácidos Carboxílicos , Antibacterianos/farmacologia , Inibidores de beta-Lactamases/farmacologia , beta-Lactamases/metabolismo , Ácidos Borínicos/farmacologia , Resistência beta-Lactâmica , Testes de Sensibilidade Microbiana
11.
Actual. SIDA. infectol ; 31(113): 42-47, 20230000. tab
Artigo em Espanhol | LILACS, BINACIS | ID: biblio-1527462

RESUMO

La emergencia de aislamientos de Klebsiella pneumoniaedoble productores de carbapenemasas (KPC y NDM) es una de las consecuencias de la pandemia causada por SARS-CoV-2 que ha causado un impacto significativo en las tasas de resistencia a los antimicrobianos en las infecciones intrahospitalarias por esta enterobacteria. Estos aislamientos representan un desafío para los servicios de salud, por su detección y caracterización y posterior tratamiento. En este trabajo se describen los aislamientos portadores de KPC y NDM recuperados durante 2022 aislados de distintas muestras clínicas de pacientes internados en un hospital universitario de la Ciudad de Buenos Aires, se los caracteriza fenotípicamente y genotípicamente como portadores de ambas carbapenemasas y se destaca la excelente actividad in vitro de la combinación ceftazidima-avibactam y aztreonam en el tratamiento de estas infecciones en donde las alternativas terapéuticas estarían limitadas a antibióticos no ß-lactámicos con porcentajes de resistencia que superan el 70%


The emergence of double-carbapenemase (KPC and NDM) producing Klebsiella pneumoniae isolates is one of the consequences derived from the SARS CoV-2 pandemic, which has caused significant impact on the antimicrobial resistance rates in hospital acquired infections. These isolates represent a real challenge for Health Services due to their difficult detection and characterization and subsequent treatment. In the present work we describe the double carbapenemase producing isolates recovered during the year 2022 from clinical samples belonging to hospitalized patients at a University Hospital in Buenos Aires city, we report their phenotypic and genotypic characterization and the excellent "in vitro" activity of the ceftazidime-avibactam-aztreonam combination in the treatment of infections in which the therapeutical options are restricted to non ß- lactamic antimicrobials which hold resistance rates higher than 70%


Assuntos
Humanos , Masculino , Feminino , Isolamento de Pacientes , Carbapenêmicos , Enterobacteriáceas Resistentes a Carbapenêmicos , Hospitais Universitários , Klebsiella pneumoniae/imunologia
12.
Diagnostics (Basel) ; 13(22)2023 Nov 09.
Artigo em Inglês | MEDLINE | ID: mdl-37998553

RESUMO

The classification of carbapenemases can help guide therapy. The present study evaluated the performance of the CPO detection test, included in the BD Phoenix™ NMIC-501 panel for the detection and classification of carbapenemases on the representative molecularly characterized strains collection from Mexico. Carbapenem non-susceptible isolates collected in Mexico were included. The clinical isolates (n = 484) comprised Klebsiella pneumoniae (n = 154), Escherichia coli (n = 150), and P. aeruginosa (n = 180). BD Phoenix CPO NMIC-504 and NMIC-501 panels were used for the identification of species, antimicrobial susceptibility tests, and detection of CPOs. For the detection of carbapenemase-encoding genes, E. coli and K. pneumoniae were evaluated using PCR assays for blaNDM-1, blaKPC, blaVIM, blaIMP, and blaOXA-48-like. For P. aeruginosa, blaVIM, blaIMP, and blaGES were detected using PCR. Regarding E. coli, the CPO panels had a sensitivity of 70% and specificity of 83.33% for the detection of a class B carbapenemase (blaNDM in the molecular test). Regarding K. pneumoniae, the panels had a sensitivity of 75% and specificity of 100% for the detection of a class A carbapenemase (blaKPC in the molecular test). The Phoenix NMIC-501 panels are reliable for detecting class B carbapenemases in E. coli. The carbapenemase classification in K. pneumoniae for class A carbapenemases has a high specificity and PPV; thus, a positive result is of high value.

13.
J Appl Microbiol ; 134(11)2023 Nov 01.
Artigo em Inglês | MEDLINE | ID: mdl-37880999

RESUMO

AIMS: Determine which sequence type (ST) clones were carrying the blaKPC, blaNDM, blaVIM, blaIMP, and blaGES genes and their variants in clinical isolates of multidrug-resistant Klebsiella pneumoniae. METHODS AND RESULTS: Ten K. pneumoniae isolates were obtained from the colonized and infected patients in a public hospital in the city of Recife-PE, in northeastern Brazil, and were further analyzed. The detection of carbapenem resistance genes and the seven housekeeping genes [for multilocus sequence typing (MLST) detection] were done with PCR and sequencing. The blaKPC and blaNDM genes were detected concomitantly in all isolates, with variants being detected blaNDM-1, blaNDM-5, blaNDM-7, and blaKPC-2. The blaKPC-2 and blaNDM-1 combination being the most frequent. Molecular typing by MLST detected three types of high-risk ST clones, associated with the clonal complex 258, ST11/CC258 in eight isolates, and ST855/CC258 and ST340/CC258 in the other two isolates. CONCLUSIONS: These findings are worrying, as they have a negative impact on the scenario of antimicrobial resistance, and show the high genetic variability of K. pneumoniae and its ability to mutate resistance genes and risk of dissemination via different ST clones.


Assuntos
Klebsiella pneumoniae , beta-Lactamases , Humanos , Klebsiella pneumoniae/genética , Tipagem de Sequências Multilocus , beta-Lactamases/genética , Brasil/epidemiologia , Células Clonais , Testes de Sensibilidade Microbiana , Antibacterianos/farmacologia
14.
Microbiol Spectr ; : e0165123, 2023 Sep 21.
Artigo em Inglês | MEDLINE | ID: mdl-37732774

RESUMO

The first cases of bla NDM in Argentina were detected in three Providencia rettgeri (Pre) recovered from two hospitals in Buenos Aires city in 2013. The isolates were genetically related, but the plasmid profile was different. Here, we characterized the bla NDM-1-harboring plasmids of the first three cases detected in Argentina. Hybrid assembly obtained from short- and long-read sequencing rendered bla NDM-1 in Col3M plasmids of ca. 320 kb (p15268A_320) in isolate PreM15268, 210 kb (p15758B_210) in PreM15758, and 225 kb (p15973A_225) in PreM15973. In addition, PreM15758 harbored a 98-kb circular plasmid (p15758C_98) flanked by a putative recombination site (hin-TnAs2), with 100% nucleotide ID and coverage with p15628A_320. Analysis of PFGE/S1-nuclease gel, Southern hybridization with bla NDM-1 probe, hybrid assembly of short and long reads suggests that pM15758C_98 can integrate by homologous recombination. The three bla NDM-1-plasmids were non-conjugative in vitro. Moreover, tra genes were incomplete, and oriT was not found in the three bla NDM-1-plasmids. In two isolates, blaNDM-1 was embedded in a partially conserved structure flanked by two ISKox2. In addition, all plasmids harbored aph(3')-Ia, aph(3')-VI, and qnrD1 genes and aac(6´)Ib-cr, bla OXA-1, catB3, and arr3 as part of a class 1 integron. Also, p15268A_320 and p15973A_225 harbored bla PER-2. To the best of our knowledge, this is the first report of clinical P. rettgeri harboring blaNDM-1 in an atypical genetic environment and located in unusual chimeric Col3M plasmids. The study and continuous surveillance of these pathogens are crucial to tracking the evolution of these resistant plasmids and finding solutions to tackle their dissemination. IMPORTANCE Infections caused by carbapenem hydrolyzing enzymes like NDM (New Delhi metallo-beta-lactamase) represent a serious problem worldwide because they restrict available treatment options and increase morbidity and mortality, and treatment failure prolongs hospital stays. The first three cases of NDM in Argentina were caused by genetically related P. rettgeri recovered in two hospitals. In this work, we studied the genetic structure of the plasmids encoding bla NDM in those index cases and revealed the enormous plasticity of these genetic elements. In particular, we found a small plasmid that was also found inserted in the larger plasmids by homologous recombination as a co-integrate element. We also found that the bla NDM plasmids were not able to transfer or move to other hosts, suggesting their role as reservoir elements for the acquisition of resistance genes. It is necessary to unravel the dissemination strategies and the evolution of these resistant plasmids to find solutions to tackle their spread.

15.
Clin Infect Dis ; 77(Suppl 1): S29-S37, 2023 07 05.
Artigo em Inglês | MEDLINE | ID: mdl-37406041

RESUMO

BACKGROUND: Carbapenemase production is a global public health threat. Antimicrobial resistance (AMR) data analysis is critical to public health policy. Here we analyzed carbapenemase detection trends using the AMR Brazilian Surveillance Network. METHODS: Carbapenemase detection data from Brazilian hospitals included in the public laboratory information system dataset were evaluated. The detection rate (DR) was defined as carbapenemase detected by gene tested per isolate per year. The temporal trends were estimated using the Prais-Winsten regression model. The impact of COVID-19 on carbapenemase genes in Brazil was determined for the period 2015-2022. Detection pre- (October 2017 to March 2020) and post-pandemic onset (April 2020 to September 2022) was compared using the χ2 test. Analyses were performed with Stata 17.0 (StataCorp, College Station, TX). RESULTS: 83 282 blaKPC and 86 038 blaNDM were tested for all microorganisms. Enterobacterales DR for blaKPC and blaNDM was 68.6% (41 301/60 205) and 14.4% (8377/58 172), respectively. P. aeruginosa DR for blaNDM was 2.5% (313/12 528). An annual percent increase for blaNDM of 41.1% was observed, and a decrease for blaKPC of -4.0% in Enterobacterales, and an annual increase for blaNDM of 71.6% and for blaKPC of 22.2% in P. aeruginosa. From 2020 to 2022, overall increases of 65.2% for Enterobacterales, 77.7% for ABC, and 61.3% for P. aeruginosa were observed in the total isolates. CONCLUSIONS: This study shows the strengths of the AMR Brazilian Surveillance Network with robust data related to carbapenemases in Brazil and the impact of COVID-19 with a change in carbapenemase profiles with blaNDM rising over the years.


Assuntos
Acinetobacter baumannii , COVID-19 , Humanos , Pseudomonas aeruginosa/genética , Carbapenêmicos/farmacologia , Acinetobacter baumannii/genética , Brasil/epidemiologia , Pandemias , COVID-19/epidemiologia , Proteínas de Bactérias/genética , beta-Lactamases/genética , Plasmídeos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana
16.
Microb Drug Resist ; 29(9): 392-400, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37486713

RESUMO

Raoultella planticola harboring genes that confer resistance to antimicrobials, such as carbapenems, have been associated with severe infections in immunocompromised patients. In this study, we reported the first whole genome sequence of a Brazilian isolate of R. planticola and the genomic context of antibiotic resistance markers. By whole-genome sequencing (WGS) of a carbapenem-resistant R. planticola isolate, RpHUM1, we found 23 resistance-encoding genes belonging to 9 classes of antibiotics (aminoglycosides, ß-lactams, fluoroquinolones, fosfomycin, macrolides, phenicols, sulfonamides, tetracycline, and diaminopyrimidine derivatives) and 3 plasmids (RpHUM1pEaer-4382s, RpHUM1_pFDAARGOS_440, and RpHUM1pRSF1010). This isolate coharbored the genes blaKPC-2, which is carried by the plasmid RpHUM1pEaer-4382s, and blaNDM-1 and blaCTX-M-15 all located in the accessory genome. In addition, these genes were associated with, at least, one mobile genetic element. This comprehensive knowledge is of great importance for implementation of control measures to prevent the rapid dissemination of this neglected microorganism and their genetic resistance background.


Assuntos
Antibacterianos , beta-Lactamases , Humanos , Antibacterianos/farmacologia , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , Sequenciamento Completo do Genoma , Plasmídeos/genética , Carbapenêmicos/farmacologia , Klebsiella pneumoniae/genética
17.
J Mycol Med ; 33(3): 101412, 2023 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-37451067

RESUMO

Onychomycosis is the most prevalent nail ailment in adults, accounting for 50% of all nail infections. Dermatophyte fungi are the primary cause, but non-dermatophyte molds (NDM) and yeasts can also cause onychomycosis. It remains important to precisely determine the fungal cause of onychomycosis since the response to current treatments may vary between fungal classes. Real-time polymerase chain reaction (qPCR) has become a widespread tool for detecting fungal organisms for diagnosis due to its sensitivity and ability to detect down to the species level. This retrospective study aims to evaluate the qPCR Onycho+ test for dermatophyte detection using remnants of toenails from a cohort of patients from Puerto Rico.  Two hundred forty-two toenail samples submitted for histological examination via Periodic acid Schiff (PAS) staining for suspected onychomycosis were analyzed by the Onycho+ test and Sanger sequencing of the internal transcribed spacer (ITS-2). Compared to the gold standard Sanger sequencing method, the Onycho+ test reported an agreement of 91.39%, a sensitivity of 100% and a specificity of 84.5% in detecting dermatophytes, superior to the histology method which had a 69.53% agreement, 85.1% sensitivity and 57.1% specificity. The distribution of fungal organisms detected in this cohort shows a dermatophyte majority but a higher-than-expected proportion of NDMs. Nails negative for the Onycho+ test and positive for histology were mostly NDMs. This study demonstrates that the clinical performance of the Onycho+ test is superior to histology in detecting dermatophytes and that a combination of Onycho+ and histology can result in a higher clinical accuracy.


Assuntos
Arthrodermataceae , Onicomicose , Adulto , Humanos , Onicomicose/diagnóstico , Onicomicose/epidemiologia , Onicomicose/microbiologia , Estudos Retrospectivos , Porto Rico/epidemiologia , Unhas/microbiologia , Leveduras , Arthrodermataceae/genética
18.
One Health ; 17: 100590, 2023 Dec.
Artigo em Inglês | MEDLINE | ID: mdl-37388191

RESUMO

Olive ridley (Lepidochelys olivacea) turtles migrate across tropical regions of the Atlantic, Pacific, and Indian Oceans. Worryingly, olive ridley populations have been declining substantially and is now considered a threatened species. In this regard, habitat degradation, anthropogenic pollution, and infectious diseases have been the most notorious threats for this species. We isolated a metallo-ß-lactamase (NDM-1)-producing Citrobacter portucalensis from the blood sample of an infected migratory olive ridley turtle found stranded sick in the coast of Brazil. Genomic analysis of C. portucalensis confirmed a novel sequence type (ST), named ST264, and a wide resistome to broad-spectrum antibiotics. The production of NDM-1 by the strain contributed to treatment failure and death of the animal. Phylogenomic relationship with environmental and human strains from African, European and Asian countries confirmed that critical priority clones of C. portucalensis are spreading beyond hospital settings, representing an emerging ecological threat to marine ecosystems.

19.
Braz J Microbiol ; 54(3): 1723-1736, 2023 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-37198419

RESUMO

Klebsiella pneumoniae is one of the major nosocomial pathogens responsible for pneumoniae, septicaemia, liver abscesses, and urinary tract infections. Coordinated efforts by antibiotic stewardship and clinicians are underway to curtail the emergence of antibiotic-resistant strains. The objective of the present study is to characterize K. pneumoniae strains through antibiotic resistance screening for production of beta-lactamases (ß-lactamases) such as extended spectrum beta lactamases (ESBLs), AmpC ß-lactamases, and carbapenemases by phenotypic and genotypic methods and genetic fingerprinting by enterobacterial repetitive intergenic consensus-polymerase chain reaction (ERIC-PCR) and repetitive element palindromic PCR (REP-PCR). A total of 85 K. pneumoniae strains isolated from 504 human urinary tract infections (UTI) were used in this study. Only 76 isolates showed positive in phenotypic screening test (PST), while combination disc method (CDM) as phenotypic confirmatory test (PCT) confirmed 72 isolates as ESBL producers. One or more ß-lactamase genes were detected by PCR in 66 isolates (91.66%, 66/72) with blaTEM gene being the most predominant (75.75%, 50/66). AmpC genes could be detected in 21 isolates (31.8%, 21/66) with FOX gene being the predominant (24.24%, 16/66), whereas NDM-I was detected in a single strain (1.51%, 1/66). Genetic fingerprinting using ERIC-PCR and REP-PCR revealed wide heterogeneity among ß-lactamase producing isolates with discriminatory power of 0.9995 and 1, respectively.


Assuntos
Infecções por Klebsiella , Infecções Urinárias , Humanos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Proteínas de Bactérias/genética , beta-Lactamases/genética , Antibacterianos/farmacologia , Reação em Cadeia da Polimerase , Testes Genéticos , Variação Genética , Infecções por Klebsiella/microbiologia
20.
Microbiol Spectr ; : e0345922, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36719202

RESUMO

We have investigated the prevalence of carbapenemase-producing uropathogens at the University Hospital of the West Indies, Jamaica. From 64 unique urine samples collected between January and March 2020, only 2 closely related Klebsiella pneumoniae (ST11, 14 SNPs of difference; no clear epidemiological links found between patients) were carbapenemase-producers. By whole-genome sequencing (WGS), blaNDM-5 was found on ~46 kb, IncX3 plasmid. These findings highlight the necessity for continuous surveillance of these pathogens in Jamaica. IMPORTANCE As the problem of antibiotic resistance continues to be a global problem, we hope to be able to shed further insight into what is happening within the Caribbean, from which there has been a paucity of data. The ability to appropriately tackle the problem of resistance requires surveillance from all territories, including resource limited settings. In this paper, we look at a mechanism of resistance that renders some critical antibiotics useless, including carbapenems, cephalosporins, and penicillin.

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