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BACKGROUND: Production of extended-spectrum ß-lactamases (ESBLs) is a common resistance mechanism in Enterobacteriaceae, leading to serious hospital-acquired infections. This study aimed to assess phenotypic, phylogenetic, and antibiotic resistance patterns among ESBL-producing Escherichia coli isolates recovered from two rural tertiary hospitals in Thailand. RESULTS: Among 467 Enterobacteriaceae isolates, E. coli was the most prevalent 356 (76.2%) followed by K. pneumoniae 88 (18.8%), K. aerogenes 8 (1.7%), K. variicola 3 (0.6%), K. quasipneumoniae 1 (0.2%%), K. oxytoca 1 (0.2%), and unidentified 9 (1.9%). Of the 202 cephalosporin-resistant E. coli isolates, 195 (96.5%) were ESBL-producing and 7 (3.5%) were non-ESBL-producing. Clermont typing revealed that phylogroup B2 was predominant (43.3%), followed by phylogroups F (11.3%), D (10.3%), C (9.7%), and A (8.7%). Among the beta-lactamase-encoding genes, blaCTX-M (83.6%) and blaTEM (81.0%) were widely found among the isolates, and blaCTX-M-1 (60.7%) was the most common among the five blaCTX-M subgroups detected. The predominant ESBL was blaCTX-M-15 (58.3%). All isolates were resistant to cefotaxime (100%) and ampicillin (100%), followed by ciprofloxacin (91.3â%), ceftazidime (72.8â%), and tetracycline (64.1%). CONCLUSION: Our findings show that phylogroup B2 was the most prevalent phylogroup among ESBL-producing E. coli isolates in northeastern Thailand. Notably, the isolates mostly carried the blaCTX-M gene(s).
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Antibacterianos , Infecciones por Escherichia coli , Escherichia coli , Pruebas de Sensibilidad Microbiana , Filogenia , beta-Lactamasas , Tailandia/epidemiología , beta-Lactamasas/genética , Humanos , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Escherichia coli/efectos de los fármacos , Escherichia coli/clasificación , Escherichia coli/enzimología , Prevalencia , Antibacterianos/farmacología , Infecciones por Escherichia coli/microbiología , Infecciones por Escherichia coli/epidemiología , Centros de Atención Terciaria/estadística & datos numéricos , Farmacorresistencia Bacteriana Múltiple/genéticaRESUMEN
Background: The transmission of carbapenemase-producing Enterobacterales (CPE) in the external environment, especially through food, presents a significant public health risk. Objectives: To investigate the prevalence and genetic characteristics of CPE in food markets of Dhaka, Bangladesh, using WGS. Methods: CPE isolates were obtained from different food and water samples collected from food markets in the southern part of Dhaka, Bangladesh. The isolates subsequently underwent molecular typing, WGS employing both short- and long-read sequencers, and plasmid analysis. Results: This study unveiled an extensive spread of CPE, with no significant difference in contamination rates observed in samples (Nâ=â136), including meat (nâ=â8), fish (nâ=â5), vegetables (nâ=â36) or various food-washed water (nâ=â65) from markets near hospitals or residential areas. Thirty-eight Enterobacterales from 33 samples carried carbapenemase genes (bla NDM-1, -4, -7, bla KPC-2, bla OXA-181 or bla IMI-1). Among these, the high-risk Escherichia coli ST410 clone was the most prevalent and distributed across various locations. Furthermore, the identification of IncHI2 plasmids co-harbouring resistance genes like bla NDM-5 and mcr-1.1, without discernible epidemiological connections, is a unique finding, suggesting their widespread dissemination. Conclusions: The analysis unveils a dynamic landscape of CPE dissemination in food markets, underscored by the proliferation of novel IncHI2 hybrid plasmids carrying both colistin- and carbapenem-resistance genes. This illuminates the ever-evolving landscape of antimicrobial resistance in Dhaka, urging us to confront its emergent challenges.
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There have been several reports of endoscopic removal of biliary metal stents using forceps or stent-in-stent techniques. Nishikawa and colleagues describe the endoscopic recovery of a proximally migrated biliary metal stent using a large dilation balloon and endoscope passage through a difficult duodenal stricture in combination with a duodenal stent.
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Sistema Biliar , Colestasis , Humanos , Constricción Patológica/cirugía , Dilatación , Endoscopios , Stents , Colangiopancreatografia Retrógrada Endoscópica , Resultado del TratamientoRESUMEN
Introduction. Carbapenemase-producing Enterobacteriaceae (CPE) have emerged as a global threat to public health and clinical practice.Hypothesis/Gap Statement. In Thailand, reports describing CPEs carrying bla NDM and bla OXA-48-like genes have been increasing recently; however, data on detailed plasmid analysis and temporal shift of sequence type and carbapenemase type are limited.Aim. In this study, we analysed whole-genome sequencing (WGS) data of clinically isolated carbapenemase-producing Klebsiella pneumoniae (CPKP) to reveal the molecular epidemiology of CPKP in a tertiary-care hospital in Bangkok, Thailand.Methodology. Seventy-seven non-duplicated CPKP isolates collected during 2013-2016 were examined for their drug-resistance genes, sequence types and phylogenetic relationships.Results. All the tested isolates possessed carbapenemase gene(s), and the major type of carbapenemase gene in 2014-2015 was bla NDM-1, whereas isolates in 2016 harboured more bla OXA-232 than bla NDM-1. Other carbapenemase gene variants, such as bla NDM-4, bla NDM-5, bla OXA-48, bla OXA-181 and bla IMP-14 were detected in some CPKP isolates. Furthermore, this study revealed that CPKP co-harbouring two genes, bla NDM-1 and bla OXA-232 or bla OXA-181, emerged during this period. Notably, such isolates co-carrying the two carbapenemase genes emerged in three different sequence types, even in a single hospital, and then spread clonally. The WGS of CPKP revealed a temporal shift of the predominant carbapenemase genes from bla NDM-1 to bla OXA-232 along with a variation in other carbapenemase gene types within a span of 4 years.Conclusion. Our findings suggest that a substantial change in CPE types occurred in Thailand and potentially in Southeast Asian countries.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Enterobacteriaceae , Humanos , Klebsiella pneumoniae/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Tailandia/epidemiología , Filogenia , Infecciones por Enterobacteriaceae/epidemiología , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Pruebas de Sensibilidad MicrobianaRESUMEN
A 74-year-old man with situs inversus totalis visited our hospital for a positive fecal occult blood. He was diagnosed with transverse colon cancer by total colonoscopy. We performed laparoscopic partial colectomy. He was discharged on the 8th postoperative day, without postoperative complications. Histopathological examination revealed well differentiated adenocarcinoma, pT1aN0M0, pStage â . Preoperative assessment of the anatomical position and vascular malformations, using 3- dimensional computed tomography, was essential for our safe surgical conduct.
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Colon Transverso , Neoplasias del Colon , Laparoscopía , Situs Inversus , Masculino , Humanos , Anciano , Colon Transverso/cirugía , Situs Inversus/complicaciones , Situs Inversus/cirugía , Neoplasias del Colon/complicaciones , Neoplasias del Colon/cirugía , Laparoscopía/métodos , ColectomíaRESUMEN
Despite frequent identification of plasmids carrying carbapenemase genes, the transfer of plasmids carrying carbapenemase genes is not well recognized in clinical settings because of technical limitations. To investigate the detailed mechanisms of the spread of carbapenem-resistant Enterobacteriaceae (CRE), we performed multifaceted genomic surveillance of CRE isolates in Thailand and analyzed their plasmidome. We analyzed 371 Enterobacteriaceae isolates carrying blaNDM-1 and 114 Enterobacteriaceae isolates carrying blaNDM-5 obtained from clinical samples of 473 patients in 11 representative hospitals located in six provinces in Thailand between 2012 and 2017. The complete structures of plasmids carrying blaNDM and chromosomal phylogeny were determined by combining Southern blotting hybridization analysis and our previously performed whole-genome short-read sequencing data. Dissemination of the blaNDM-5 gene among the Enterobacteriaceae isolates in Thailand was mainly owing to the nationwide clonal spread of Escherichia coli ST410 and regional clonal spreads of Escherichia coli ST361 and ST405. Analysis of blaNDM-1-carrying isolates revealed nationwide dissemination of two specific plasmids and nationwide clonal dissemination of Klebsiella pneumoniae ST16 accompanied with regional disseminations of three distinctive K. pneumoniae clones (ST231, ST14, and ST147) with different plasmids. Dissemination of CRE carrying blaNDM in Thailand is mainly based on nationwide clonal expansions of E. coli ST410 carrying blaNDM-5 and K. pneumoniae ST16 carrying blaNDM-1, nationwide dissemination of two distinctive plasmids carrying blaNDM-1, and accumulation of clonal expansions in regional areas. Although the overuse of antibiotics can promote CRE dissemination, the limited variety of transmitters highlights the importance of preventing horizontal dissemination among patients.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Enterobacteriaceae , Humanos , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Escherichia coli/genética , Infecciones por Enterobacteriaceae/epidemiología , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Tailandia/epidemiología , Pruebas de Sensibilidad Microbiana , beta-Lactamasas/genética , Enterobacteriaceae/genética , Plásmidos/genética , Klebsiella pneumoniae/genética , Antibacterianos/farmacología , Antibacterianos/uso terapéuticoRESUMEN
Background: Streptococcus suis is a zoonotic pathogen that can cause invasive infections in humans who are in close contact with infected pigs or contaminated pork-derived products. S. suis serotype 2 sequence type (ST) 1 strains are mostly associated with meningitis, whereas ST104 strains are mostly recovered from sepsis cases in humans. No data are available for comparison of the ST1 and ST104 strains at the genomic level, particularly concerning virulence-associated genes. Thus, genomic comparison of both STs was performed in this study. Methods: An ST1 isolate (ID26154) from the cerebrospinal fluid of a patient with meningitis and an ST104 isolate (ID24525) from the blood of a patient with sepsis were subjected to shotgun pyrosequencing using the 454 GS Junior System. Genomic comparison was conducted between the ST1 isolate and the ST104 isolate using the Artemis Comparison Tool (ACT) to identify the region of differences (RDs) between ST1 and ST104. Results: Fifty-eight RDs were unique to the ST104 genome and were mainly involved in metabolism and cell functional activities, cell wall anchored proteins, bacteriophages and mobile genetic elements, ABC-type transporters, two-component signal transductions, and lantibiotic proteins. Some virulence genes mostly found in ST1 strains were also present in the ST104 genome. Whole-genome comparison is a powerful tool for identifying genomic region differences between different STs of S. suis serotype 2, leading to the identification of the molecular basis of virulence involved in the pathogenesis of the infection.
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Sepsis , Infecciones Estreptocócicas , Streptococcus suis , Humanos , Animales , Porcinos , Streptococcus suis/genética , Serogrupo , Infecciones Estreptocócicas/genética , Genómica , Sepsis/genéticaRESUMEN
Background: Klebsiella pneumoniae ST258 and ST11 carrying bla KPC are among the most widespread carbapenem-resistant K. pneumoniae strains worldwide. Our carbapenem-resistant Enterobacteriaceae surveillance in Thailand revealed a nationwide dissemination of K. pneumoniae ST16 isolates carrying bla NDM-1 and bla OXA-232. Objectives: To analyse the genomic details of this nationwide dissemination by focusing on plasmids and virulence factors. Methods: Using WGS data of 119 K. pneumoniae ST16 isolates carrying bla NDM-1 obtained in our previous surveillance study, clonality of chromosomes and plasmids of the isolates with carriage of virulence factors was evaluated. Results: Of the 119 isolates, 111 carried plasmid pKP151_NDM1, and all 104 isolates harbouring bla OXA-232 carried plasmid pKP151_OXA232. These 104 K. pneumoniae ST16 isolates showing chromosomal clonality possessed both pKP151_NDM1 and pKP151_OXA232, demonstrating clonal dissemination of K. pneumoniae ST16 with these plasmids. The isolates had essentially similar virulence factors as those of K. pneumoniae ST16 clones carrying bla KPC, which were recently reported as highly invasive clones in Brazil. Conclusions: The potential global dissemination of these invasive clones with resistance to several antibiotics highlights the importance of appropriate monitoring and strict standard precautions.
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BACKGROUND: Covid-19 vaccination has started in the majority of the countries at the global level. Cancer patients are at high risk for infection, serious illness, and death from COVID-19 and need vaccination guidance and support. Guidance availability in the English language only is a major limit for recommendations' delivery and their application in the world's population and generates information inequalities across the different populations. METHODS: Most of the available COVID-19 vaccination guidance for cancer patients was screened and scrutinized by the European Cancer Patients Coalition (ECPC) and an international oncology panel of 52 physicians from 33 countries. RESULTS: A summary guidance was developed and provided in 28 languages in order to reach more than 70 percent of the global population. CONCLUSION: Language barrier and e-guidance availability in the native language are the most important barriers when communicating with patients. E-guidance availability in various native languages should be considered a major priority by international medical and health organizations that are communicating with patients at the global level.
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COVID-19 , Neoplasias , COVID-19/epidemiología , COVID-19/prevención & control , Vacunas contra la COVID-19 , Humanos , Lenguaje , VacunaciónRESUMEN
Nishikawa and colleagues describe a case of endoscopic multiple stenting for malignant biliary stenosis in a patient with complexly altered digestive anatomy following hepaticojejunostomy with Roux-en-Y anastomosis and gastrojejunostomy with Braun enterostomy. Furthermore, reintervention for malignant stenosis extending from the intrahepatic bile duct to the intestinal tract was successfully completed.
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Procedimientos Quirúrgicos del Sistema Biliar , Colestasis , Colangiopancreatografia Retrógrada Endoscópica , Colestasis/cirugía , Constricción Patológica/cirugía , Humanos , StentsRESUMEN
Fifteen Klebsiella pneumoniae isolates harbouring bla NDM genes were identified from blood and sputum specimens of patients at a tertiary-care facility (Yangon General Hospital, Yangon, Myanmar) in 2018. Two of the isolates belonged to sequence type (ST) 11, an international high-risk clone. Whole-genome sequencing and phylogenetic analyses revealed that these two isolates were clustered together with other ST11 isolates originating from other countries. The isolates harboured the bla NDM-5 gene on an IncFII-type plasmid that is prevalent among carbapenemase-producing Enterobacteriaceae in Yangon but has rarely been found in other ST11 isolates. Our data suggests the regional presence of the ST11 international high-risk clone and its acquisition of an endemic bla NDM-5-carrying plasmid.
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Enterobacteriaceae Resistentes a los Carbapenémicos , Infecciones por Klebsiella/microbiología , Klebsiella pneumoniae , Resistencia betalactámica/genética , beta-Lactamasas/genética , Proteínas Bacterianas/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Hospitales Generales , Humanos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Mianmar/epidemiología , Plásmidos , Centros de Atención TerciariaRESUMEN
BACKGROUND: Carbapenemase-producing Enterobacterales (CPE) are spreading in hospitals, environment and retail foods in Yangon, Myanmar. OBJECTIVES: To investigate whether CPE colonize healthy individuals living in Yangon and whether clinical-related strains are spreading in the community. METHODS: CPE was isolated from faecal samples obtained from healthy Japanese residents of Yangon with no history of hospitalization. Isolates were subjected to WGS using short- and long-read sequencers and compared with those previously isolated in Yangon. RESULTS: Six Escherichia coli strains harbouring blaNDM-1 or blaNDM-5 belonging to five different STs-ST10, ST38, ST48, ST410 and ST8453-were isolated from 69 volunteers. The ST38 isolates were related to those previously isolated from retail food in Yangon. The ST410 and ST8453 isolates were highly related to previous Yangon isolates including those of clinical and food origins. CONCLUSIONS: The analysis suggested the acquisition of blaNDM-positive E. coli, which are disseminating in a clinical setting and through retail foods, by healthy residents in Yangon.
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Infecciones por Escherichia coli , Escherichia coli , Antibacterianos/farmacología , Escherichia coli/genética , Infecciones por Escherichia coli/epidemiología , Humanos , Japón/epidemiología , Pruebas de Sensibilidad Microbiana , Mianmar/epidemiología , beta-Lactamasas/genéticaRESUMEN
BACKGROUND: Acinetobacter baumannii is recognized as a majority opportunistic nosocomial pathogen causing hospital-acquired infection worldwide. The increasing prevalence of extensively drug-resistant Acinetobacter baumannii (XDRAB) has become a rising concern in healthcare facilities and has impeded public health due to limitation of therapeutic options and are associated with high morbidity and mortality as well as longer hospitalization. Whole-genome sequencing of highly multidrug resistant A. baumannii will increase the understanding of resistant mechanisms, the emergence of novel resistance, genetic relationships among the isolates, source tracking, and treatment decisions in selected patients. OBJECTIVE: This study revealed the genomic analysis to explore blaOXA-23 harboring XDRAB isolates in Thailand. METHODS: Whole-genome sequencing of the two XDRAB isolates was carried out on a HiSeq2000 Illumina platform and susceptibility on antimicrobials was conducted. RESULTS: Both isolates revealed sequence types of international, clone II-carrying, multiple antimicrobial- resistant genes-ST195 and ST451. They were resistant to antimicrobial agents in all drug classes tested for Acinetobacter spp. They carried 18 antimicrobial-resistant genes comprising of 4 ß-lactamase genes (blaOXA-23, blaOXA-66, blaTEM-1D, blaADC-25), 4 aminoglycoside-resistant genes (armA, aph(3')-Ia, aph(3")-Ib, aph(6)-Id), 3 macrolide-resistant genes (amvA, mphE, msrE), 1 sulfonamide- resistant gene (sul-2), 2 tetracycline-resistant genes (tetB, tetR), 1 resistant-nodulation-cell division (RND) antibiotic efflux pump gene cluster, 2 major facilitator superfamily (MFS) antibiotic efflux pump genes (abaF, abaQ), and 1 small multidrug-resistant (SMR) antibiotic efflux pump gene (abeS). Mutation of gyrA (S81L) occurred in both isolates. CONCLUSION: Whole-genome sequencing revealed both blaOXA-23 harboring XDRAB isolates were clustered under international clone II with different STs and carrying multiple antimicrobial-resistant genes conferred their resistance to antimicrobial agents. Inactivation of antimicrobials and target modification by enzymes and pumping antibiotics by efflux pump are mainly resistance mechanism of the XDRAB in this study.
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Infecciones por Acinetobacter , Acinetobacter baumannii , Preparaciones Farmacéuticas , Infecciones por Acinetobacter/tratamiento farmacológico , Acinetobacter baumannii/genética , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Farmacorresistencia Bacteriana Múltiple/genética , Humanos , Pruebas de Sensibilidad Microbiana , Tailandia , beta-LactamasasRESUMEN
The resistance of Gram-negative bacteria to colistin, mediated by plasmid-borne mcr genes, is an emerging public health concern. The complete genome sequence (4.55 Mb) of a clinical isolate of Aeromonas veronii biovar veronii obtained from a patient with septicemia was determined using short-read and long-read platforms. This isolate (C198) was found to harbor a novel mcr-3 gene, designated mcr-3.41. Isolate C198 revealed adjacent mcr-3.41 and mcr-3-like genes. It contained one chromosome and two plasmids, both of which encoded a RepB replication protein. Other antimicrobial resistance genes, including blacphA3, blaOXA-12, tetA, rsmA, and adeF, were also present. Isolate C198 was resistant to amoxicillin-clavulanate, ampicillin-sulbactam and tetracycline, and showed intermediate resistance to trimethoprim-sulfamethoxazole. The isolate was susceptible to piperacillin-tazobactam, carbapenem, third-generation cephalosporins, fluoroquinolones, chloramphenicol, and aminoglycosides. Putative virulence genes in the C198 genome encoded type II, III, and VI secretion systems; type IV Aeromonas pili; and type I fimbria, flagella, hemagglutinin, aerolysin, and hemolysins. Multilocus sequence typing revealed a novel sequence type (ST), ST720 for C198. Phylogenetic analysis of the single nucleotide polymorphisms in C198 demonstrated that the strain was closely related to A. veronii 17ISAe. The present study provides insights into the genomic characteristics of human A. veronii isolates.
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Carbapenem-resistant Enterobacteriaceae (CRE) infections, high in morbidity and mortality, pose serious clinical challenges due to limited treatment options. A previous CRE surveillance study on 1,507 patients from 43 hospitals in Osaka, Japan, revealed that 12% of patients carried CRE and that 95% of the CRE isolates were IMP-type carbapenemase producers. Here, the mechanisms for this regional dissemination of a single carbapenemase gene were investigated. Since the dissemination of CRE is primarily due to the transmission of carbapenemase genes located on plasmids, we analyzed the plasmidome of 230 CRE isolates carrying bla IMP by whole-genome sequencing and Southern blotting. bla IMP-6 was found to be predominantly disseminated among chromosomally distinct isolates through the pKPI-6 plasmid. Underlying the vast clonal dissemination of pKPI-6, various subpopulations deriving from pKPI-6 were identified, which had acquired advantages for the dissemination of CRE isolates. A cluster exhibiting heteroresistance against meropenem by the transcriptional regulation of bla IMP-6 caused an outbreak likely through covert transmission of bla IMP-6 For stable carriage of bla IMP-6, they occasionally integrated bla IMP-6 on their chromosomes. In addition, we detected one isolate that broadened the range of antimicrobial resistance through a single point mutation in bla IMP-6 on pKPI-6. Multifaceted analysis of the plasmidome granted us more accurate perspectives on the horizontal spread of CRE isolates, which is difficult to trace only by comparing the whole genomes. This study revealed the predominant spread of a specific carbapenemase-encoding plasmid accompanying the emergence of phenotypically diverse derivatives, which may facilitate further dissemination of CRE in various environments.IMPORTANCE Global dissemination of carbapenem-resistant Enterobacteriaceae (CRE) threatens human health by limiting the efficacy of antibiotics even against common bacterial infections. Carbapenem resistance, mainly due to carbapenemase, is generally encoded on plasmids and is spread across bacterial species by conjugation. Most CRE epidemiological studies have analyzed whole genomes or only contigs of CRE isolates. Here, plasmidome analysis on 230 CRE isolates carrying bla IMP was performed to shed light into the dissemination of a single carbapenemase gene in Osaka, Japan. The predominant dissemination of bla IMP-6 by the pKPI-6 plasmid among genetically distinct isolates was revealed, as well as the emergences of pKPI-6 derivatives that acquired advantages for further disseminations. Underlying vast clonal dissemination of a carbapenemase-encoding plasmid, heteroresistance was found in CRE offspring, which was generated by the transcriptional regulation of bla IMP-6, stabilization of bla IMP-6 through chromosomal integration, or broadened antimicrobial resistance due to a single point mutation in bla IMP-6.
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Streptococcus suis is a zoonotic pathogen of economic significance to the swine industry. The number of infected cases is increasing in humans worldwide. In this study, we determined the prevalence and diversity of S. suis carriage in slaughterhouse pigs in Phayao province, Thailand, where an outbreak occurred in 2007. The overall S. suis carriage rate was 35.2% among slaughterhouse pigs. The prevalence rates of serotypes 2 and 14 (the major serotypes infected in humans) were 6.7% and 2.6%, respectively. In both serotypes, 70.4% of isolates of serotypes 2 and 14 revealed sequence types and pulsotypes identical to human isolates in Thailand. It is suggested that pathogenic strains of S. suis are a risk factor for occupational exposure to pigs or the consumption of raw pork products. Food safety, hygiene, and health education should be encouraged to reduce the risk group.
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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.
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Antibacterianos/farmacología , Cefmetazol/farmacología , Infecciones por Enterobacteriaceae/tratamiento farmacológico , Enterobacteriaceae/efectos de los fármacos , Meropenem/farmacología , Antibacterianos/uso terapéutico , Cefmetazol/uso terapéutico , Quimioterapia Combinada , Enterobacteriaceae/metabolismo , Infecciones por Enterobacteriaceae/microbiología , Ertapenem/farmacología , Humanos , Meropenem/uso terapéutico , beta-Lactamasas/biosíntesisRESUMEN
The rapidly increasing prevalence of carbapenem-resistant Enterobacteriaceae (CRE) over the past decade has increased concern in healthcare facilities and the impact on public health. The prevalence of blaKPC (KPC) in Thailand remains very low; only blaKPC-13 has been described previously. This study is the first to describe the characteristics of blaKPC-2-carrying Klebsiella pneumoniae, Escherichia coli, and Enterobacter asburiae in Thailand. The prevalence rate of blaKPC-2-carrying isolates was 0.13% among CRE isolates in our study. Based on carbapenem susceptibility testing, K. pneumoniae C1985 was resistant to meropenem and ertapenem, E. coli C1992 was resistant to meropenem, imipenem, and ertapenem, and E. asburiae C2135 was only resistant to imipenem. K. pneumoniae C1985 carried blaKPC-2, blaSHV-11, fosA, oqxA, and oqxB, while E. coli C1992 contained blaKPC-2 and mdf(A) and E. asburiae C2135 harbored blaKPC-2, blaACT-2, and qnrE1. The genetic features of blaKPC-2 in the 3 isolates revealed identical rearrangement and flanking regions. Analysis of genomic sequences from these 3 isolates revealed that the sequence types of K. pneumoniae C1985, E. coli C1992, and E. asburiae C2135 were ST4008, ST7297, and ST1249, respectively. The 3 blaKPC-2 isolates were from individual living cases. Two cases were colonization for K. pneumoniae C1985 and E. asburiae C2135 and the third case was hospital-acquired infection of E. coli C1992. Although the prevalence of blaKPC-2-carrying CRE is relatively low in this study, continued surveillance and close monitoring are warranted. In addition, prompt or early detection of CRE and strict implementation of infection control are essential to prevent outbreaks or rapid spread in hospitals.
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Antibacterianos/farmacología , Proteínas Bacterianas/genética , Enterobacteriaceae Resistentes a los Carbapenémicos/genética , Carbapenémicos/farmacología , Infecciones por Enterobacteriaceae/tratamiento farmacológico , beta-Lactamasas/genética , Adulto , Anciano , Antibacterianos/uso terapéutico , Enterobacteriaceae Resistentes a los Carbapenémicos/efectos de los fármacos , Enterobacteriaceae Resistentes a los Carbapenémicos/aislamiento & purificación , Carbapenémicos/uso terapéutico , Enterobacter/efectos de los fármacos , Enterobacter/genética , Enterobacter/aislamiento & purificación , Infecciones por Enterobacteriaceae/microbiología , Escherichia coli/efectos de los fármacos , Escherichia coli/genética , Escherichia coli/aislamiento & purificación , Femenino , Genoma Bacteriano , Humanos , Klebsiella pneumoniae/efectos de los fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/aislamiento & purificación , Masculino , Pruebas de Sensibilidad Microbiana , Persona de Mediana Edad , Tipificación Molecular , Secuenciación Completa del Genoma , Resistencia betalactámica/genéticaRESUMEN
The spread of carbapenemase-producing Enterobacteriaceae (CPE) poses a serious threat to clinical practice and public health. These bacteria are present both in clinical settings and non-clinical environments. The presence of CPE in food stuffs has been reported, but sporadically so. Here, we screened for CPE in meat, seafood, and vegetable samples from local markets of Yangon, Myanmar. We obtained 27 CPE isolates from 93 food samples and identified 13 as Escherichia coli, six as Klebsiella pneumoniae, seven as Enterobacter cloacae complex, and one as Serratia marcescens. All except the E. cloacae complex harboured the carbapenemase genes blaNDM-1 or blaNDM-5, while all Enterobacter isolates carried the carbapenemase gene blaIMI-1. The blaIMI-1 gene was located in putative mobile elements EcloIMEX-2, -3, or -8. Using multi-locus sequence typing, E. coli, K. pneumoniae, and E. cloacae complex isolates were classified into 10, six, and five different sequence types, respectively. Our results demonstrate that diverse organisms with various carbapenemase genes are widespread in the market foods in Yangon, highlighting the need for promoting proper food hygiene and effective measures to prevent further dissemination.