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1.
BMC Infect Dis ; 21(1): 637, 2021 Jul 02.
Artigo em Inglês | MEDLINE | ID: mdl-34215203

RESUMO

BACKGROUND: Cedecea neteri is a gram-negative, oxidase-negative bacillus, a rare pathogen. Few reports are emerging globally about its antimicrobial resistance pattern especially in immunocompromised individuals with comorbidities. CASE PRESENTATION: In this paper, we report the first case of C. neteri causing urinary tract infection in a pregnant woman at a specialty care hospital in the Northern Emirates of Ras al Khaimah, UAE. DISCUSSION AND CONCLUSION: C. neteri is a rare and unusual pathogen, unlike routine gram-negative urinary tract pathogens from the family of Enterobacteriaceae and therefore may be missed or misidentified by routine laboratories using conventional microbiology identification techniques. Hence, Cedecea infections may be under-reported. Physicians and microbiology technicians must be aware of such a rare pathogen, as most of the isolates are multi-drug-resistant and require combined antibiotic treatment with beta-lactamase inhibitors and hence pose a treatment challenge especially in immunocompromised patients with comorbidities. In recent years, it has been reported as an emerging opportunistic pathogen.


Assuntos
Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , Poli-Hidrâmnios/fisiopatologia , Gestantes , Infecções Urinárias/epidemiologia , Adulto , Antibacterianos/uso terapêutico , Enterobacteriaceae/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Gravidez , Prognóstico , Emirados Árabes Unidos/epidemiologia , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/microbiologia
2.
BMC Infect Dis ; 21(1): 600, 2021 Jun 23.
Artigo em Inglês | MEDLINE | ID: mdl-34162341

RESUMO

BACKGROUND: This antimicrobial surveillance study reports in vitro antimicrobial activity and susceptibility data for a panel of agents against respiratory isolates of Enterobacterales and Pseudomonas aeruginosa. METHODS: Isolates from respiratory specimens were collected in Africa/Middle East, Asia/South Pacific, Europe and Latin America between 2016 and 2018, as part of the Antimicrobial Testing Leadership and Surveillance (ATLAS) program. Broth microdilution methodology was used to quantify minimum inhibitory concentrations, from which rates of susceptibility were determined using EUCAST breakpoints (version 10). Rates of subsets with genes encoding ß-lactamases (extended-spectrum ß-lactamases [ESBLs], serine carbapenemases and metallo-ß-lactamases [MBLs]) were also determined, as well as rates of multidrug-resistant (MDR) P. aeruginosa. RESULTS: Among all respiratory Enterobacterales isolates, susceptibility to ceftazidime-avibactam, meropenem, colistin and amikacin was ≥94.4% in each region. For Enterobacterales isolates that were ESBL-positive or carbapenemase-positive/MBL-negative, ceftazidime-avibactam susceptibility was 93.6 and 98.9%, respectively. Fewer than 42.7% of MBL-positive Enterobacterales isolates were susceptible to any agents, except colistin (89.0% susceptible). Tigecycline susceptibility was ≥90.0% among Citrobacter koseri and Escherichia coli isolates, including all ß-lactamase-positive subsets. ESBL-positive Enterobacterales were more commonly identified in each region than isolates that were ESBL/carbapenemase-positive; carbapenemase-positive/MBL-negative; or MBL-positive. Among all respiratory P. aeruginosa isolates, the combined susceptibility rates (susceptible at standard dosing regimen plus susceptible at increased exposure) were highest to ceftazidime-avibactam, colistin and amikacin (≥82.4% in each region). Susceptibility to colistin was ≥98.1% for all ß-lactamase-positive subsets of P. aeruginosa. The lowest rates of antimicrobial susceptibility were observed among MBL-positive isolates of P. aeruginosa (≤56.6%), with the exception of colistin (100% susceptible). MDR P. aeruginosa were most frequently identified in each region (18.7-28.7%), compared with the subsets of ESBL-positive; carbapenemase-positive/MBL-negative; or MBL-positive isolates. CONCLUSIONS: Rates of susceptibility among the collections of respiratory Enterobacterales and P. aeruginosa isolates were highest to ceftazidime-avibactam, colistin and amikacin in each region. Tigecycline was active against all subsets of C. koseri and E. coli, and colistin was active against all subsets of P. aeruginosa. The findings of this study indicate the need for continued antimicrobial surveillance among respiratory Gram-negative pathogens, in particular those with genes encoding MBLs.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/isolamento & purificação , Amicacina/farmacologia , Compostos Azabicíclicos/farmacologia , Proteínas de Bactérias/genética , Ceftazidima/farmacologia , Citrobacter koseri/efeitos dos fármacos , Citrobacter koseri/isolamento & purificação , Colistina/farmacologia , Combinação de Medicamentos , Monitoramento Epidemiológico , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Humanos , Meropeném/farmacologia , Testes de Sensibilidade Microbiana , Tigeciclina/farmacologia , beta-Lactamases/genética
3.
Int J Mol Sci ; 22(7)2021 Mar 24.
Artigo em Inglês | MEDLINE | ID: mdl-33804887

RESUMO

Ultrashort cationic lipopeptides (USCLs) and gemini cationic surfactants are classes of potent antimicrobials. Our recent study has shown that the branching and shortening of the fatty acids chains with the simultaneous addition of a hydrophobic N-terminal amino acid in USCLs result in compounds with enhanced selectivity. Here, this approach was introduced into arginine-rich gemini cationic surfactants. l-cystine diamide and l-lysine amide linkers were used as spacers. Antimicrobial activity against planktonic and biofilm cultures of ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter spp.) strains and Candida sp. as well as hemolytic and cytotoxic activities were examined. Moreover, antimicrobial activity in the presence of human serum and the ability to form micelles were evaluated. Membrane permeabilization study, serum stability assay, and molecular dynamics were performed. Generally, critical aggregation concentration was linearly correlated with hydrophobicity. Gemini surfactants were more active than the parent USCLs, and they turned out to be selective antimicrobial agents with relatively low hemolytic and cytotoxic activities. Geminis with the l-cystine diamide spacer seem to be less cytotoxic than their l-lysine amide counterparts, but they exhibited lower antibiofilm and antimicrobial activities in serum. In some cases, geminis with branched fatty acid chains and N-terminal hydrophobic amino acid resides exhibited enhanced selectivity to pathogens over human cells.


Assuntos
Peptídeos Catiônicos Antimicrobianos/síntese química , Biofilmes/efeitos dos fármacos , Lipoproteínas/síntese química , Tensoativos/síntese química , Motivos de Aminoácidos , Peptídeos Catiônicos Antimicrobianos/farmacologia , Arginina/química , Candida/efeitos dos fármacos , Membrana Celular/efeitos dos fármacos , Cistina/química , Enterobacteriaceae/efeitos dos fármacos , Ácidos Graxos/química , Hemólise , Interações Hidrofóbicas e Hidrofílicas , Lipoproteínas/farmacologia , Lisina/química , Micelas , Tensoativos/farmacologia
4.
J Med Microbiol ; 70(4)2021 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-33830906

RESUMO

Introduction. Nitrofurantoin is one of the preferred antibiotics in the treatment of uropathogenic multidrug-resistant (MDR) infections. However, resistance to nitrofurantoin in extensively drug-resistant (XDR) bacteria has severely limited the treatment options.Gap statement. Information related to co-resistance or collateral sensitivity (CS) with reference to nitrofurantoin resistant bacteria is limited.Aim. To study the potential of nitrofurantoin resistance as an indicator of the XDR phenotype in Enterobacteriaceae.Methods. One hundred (45 nitrofurantoin-resistant, 21 intermediately resistant and 34 nitrofurantoin-susceptible) Enterobacteriaceae were analysed in this study. Antibiotic susceptibility testing (AST) against nitrofurantoin and 17 other antimicrobial agents across eight different classes was performed by using the Vitek 2.0 system. The isolates were screened for the prevalence of acquired antimicrobial resistance (AMR) and efflux pump genes by PCR.Results. In total, 51 % of nitrofurantoin-resistant and 28 % of intermediately nitrofurantoin resistant isolates exhibited XDR characteristics, while only 3 % of nitrofurantoin-sensitive isolates were XDR (P=0.0001). Significant co-resistance was observed between nitrofurantoin and other tested antibiotics (ß-lactam, cephalosporin, carbapenem, aminoglycoside and tetracycline). Further, the prevalence of AMR and efflux pump genes was higher in the nitrofurantoin-resistant strains compared to the susceptible isolates. A strong association was observed between nitrofurantoin resistance and the presence of bla PER-1, bla NDM-1, bla OXA-48, ant(2) and oqxA-oqxB genes. Tigecycline (84 %) and colistin (95 %) were the only antibiotics to which the majority of the isolates were susceptible.Conclusion. Nitrofurantoin resistance could be an indicator of the XDR phenotype among Enterobacteriaceae, harbouring multiple AMR and efflux pump genes. Tigecycline and colistin are the only antibiotics that could be used in the treatment of such XDR infections. A deeper understanding of the co-resistance mechanisms in XDR pathogens and prescription of AST-based appropriate combination therapy may help mitigate this problem.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Nitrofurantoína/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/fisiologia , Infecções por Enterobacteriaceae/microbiologia , Humanos , Testes de Sensibilidade Microbiana
5.
Appl Environ Microbiol ; 87(10)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33674437

RESUMO

Octenidine-based disinfection products are becoming increasingly popular for infection control of multidrug-resistant (MDR) Gram-negative isolates. When a waste trap was removed from a hospital and allowed to acclimatize in a standard tap rig in our laboratory, it was shown that Klebsiella pneumoniae, Pseudomonas aeruginosa, and Citrobacter and Enterobacter spp. were readily isolated. This study aimed to understand the potential impact of prolonged exposure to low doses of a commercial product containing octenidine on these bacteria. Phenotypic and genotypic analyses showed that P. aeruginosa strains had increased tolerance to octenidine, which was characterized by mutations in the Tet repressor SmvR. Enterobacter species demonstrated increased tolerance to many other cationic biocides, although not octenidine, as well as the antibiotics ciprofloxacin, chloramphenicol, and ceftazidime, through mutations in another Tet repressor, RamR. Citrobacter species with mutations in RamR and MarR were identified following octenidine exposure, and this is linked to development of resistance to ampicillin, piperacillin, and chloramphenicol, as well as an increased MIC for ciprofloxacin. Isolates were able to retain fitness, as characterized by growth, biofilm formation, and virulence in Galleria mellonella, after prolonged contact with octenidine, although there were strain-to-strain differences. These results demonstrate that continued low-level octenidine exposure in a simulated sink trap environment selects for mutations that affect smvR It may also promote microbial adaptation to other cationic biocides and cross-resistance to antibiotics, while not incurring a fitness cost. This suggests that hospital sink traps may act as a reservoir for more biocide-tolerant organisms.IMPORTANCE Multidrug-resistant (MDR) strains of bacteria are a major clinical problem, and several reports have linked outbreaks of MDR bacteria with bacterial populations in hospital sinks. Biocides such as octenidine are used clinically in body washes and other products, such as wound dressings for infection control. Therefore, increased tolerance to these biocides would be detrimental to infection control processes. Here, we exposed bacterial populations originally from hospital sink traps to repeated dosing with an octenidine-containing product over several weeks and observed how particular species adapted. We found mutations in genes related to biocide and antibiotic susceptibility, which resulted in increased tolerance, although this was species dependent. Bacteria that became more tolerant to octenidine also showed no loss of fitness. This shows that prolonged octenidine exposure has the potential to promote microbial adaptation in the environment and that hospital sink traps may act as a reservoir for increased biocide- and antibiotic-tolerant organisms.


Assuntos
Anti-Infecciosos/farmacologia , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Proteínas de Membrana Transportadoras/genética , Pseudomonas aeruginosa/efeitos dos fármacos , Piridinas/farmacologia , Enterobacteriaceae/genética , Enterobacteriaceae/crescimento & desenvolvimento , Hospitais , Mutação , Pseudomonas aeruginosa/genética , Pseudomonas aeruginosa/crescimento & desenvolvimento , Eliminação de Resíduos Líquidos
6.
Appl Environ Microbiol ; 87(10)2021 04 27.
Artigo em Inglês | MEDLINE | ID: mdl-33674440

RESUMO

We investigated the prevalence and transmission of NDM-producing Enterobacteriaceae in fecal samples of geese and environmental samples from a goose farm in southern China. The samples were cultivated on MacConkey agar plates supplemented with meropenem. Individual colonies were examined for bla NDM, and bla NDM-positive bacteria were characterized based on whole-genome sequencing (WGS) data from the Illumina and Oxford Nanopore Technologies (ONT) platforms. Of 117 samples analyzed, the carriage rates for New Delhi metallo-ß-lactamase (NDM)-positive Enterobacteriaceae were 47.1, 18, and 50% in geese, inanimate environments (sewage, soil, fodder, and dust), and mouse samples, respectively. Two variants (bla NDM-1 and bla NDM-5, in 4 and 40 isolates, respectively) were found among 44 bla NDM-positive Enterobacteriaceae; these variants belonged to eight species, and Escherichia coli was the most prevalent (50%). WGS analysis revealed that bla NDM coexisted with diverse antibiotic resistance genes (ARGs). Population structure analysis showed that most E. coli and Enterobacter sp. isolates were highly heterogeneous, while most Citrobacter sp. and P. stuartii isolates possessed extremely high genetic similarities. In addition, bla NDM-5-positive ST4358/ST48 E. coli isolates were found to be clonally spread between geese and the environment and were highly genetically similar to those reported from ducks, farm environments, and humans in China. Plasmid analysis indicated that IncX3 pHNYX644-1-like (n = 40) and untypeable pM2-1-like plasmids (n = 4) mediated bla NDM spread. pM2-1-like plasmids possessed diverse ARGs, including bla NDM-1, the arsenical and mercury resistance operons, and the maltose operon. Our findings revealed that the goose farm is a reservoir for NDM-positive Enterobacteriaceae The bla NDM contamination of wild mice and the novel pM2-1-like plasmid described here likely adds to the risk for dissemination of bla NDM and associated resistance genes.IMPORTANCE Carbapenem-resistant bacteria, in particular NDM-producing Enterobacteriaceae, have become a great threat to global public. These bacteria have been found not only in hospital and community environments but also among food animal production chains, which are recognized as reservoirs for NDM-producing Enterobacteriaceae However, the dissemination of NDM-producing bacteria in waterfowl farms has been less well explored. Our study demonstrates that the horizontal spread of bla NDM-carrying plasmids and the partial clonal spread of bla NDM-positive Enterobacteriaceae contribute to the widespread contamination of bla NDM in the goose farm ecosystem, including mice. Furthermore, we found a novel and transferable bla NDM-1-carrying multidrug resistance (MDR) plasmid that possessed multiple environmental adaptation-related genes. The outcomes of this study contribute to a better understanding of the prevalence and transmission of bla NDM-carrying Enterobacteriaceae among diverse niches in the farm ecosystem.


Assuntos
Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/isolamento & purificação , Gansos/microbiologia , Doenças das Aves Domésticas/microbiologia , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , China , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/veterinária , Fazendas , Fezes/microbiologia , Fômites/microbiologia , Camundongos , Testes de Sensibilidade Microbiana
7.
J Travel Med ; 28(3)2021 04 14.
Artigo em Inglês | MEDLINE | ID: mdl-33675647

RESUMO

BACKGROUND: International travel is a risk factor for incident colonization with extended spectrum beta-lactamase (ESBL)-producing organisms. These and other multidrug-resistant (MDR) bacteria are major pathogens in combat casualties. We evaluated risk factors for colonization with MDR bacteria in US military personnel travelling internationally for official duty. METHODS: TravMil is a prospective observational study enrolling subjects presenting to military travel clinics. We analysed surveys, antimicrobial use data, and pre- and post-travel perirectal swabs in military travellers to regions outside the continental USA, Canada, Western or Northern Europe, or New Zealand, presenting to one clinic from 12/2015 to 12/2017. Recovered Gram-negative isolates underwent identification and susceptibility testing (BD Phoenix). Characteristics of trip and traveller were analysed to determine risk factors for MDR organism colonization. RESULTS: 110 trips were planned by 99 travellers (74% male, median age 38 years [IQR 31, 47.25]); 72 trips with returned pre- and post-travel swabs were completed by 64 travellers. Median duration was 21 days (IQR 12.75, 79.5). 17% travelled to Mexico/Caribbean/Central America, 15% to Asia, 57% to Africa and 10% to South America; 56% stayed in hotels and 50% in dormitories/barracks. Travellers used doxycycline (15%) for malaria prophylaxis, 11% took an antibiotic for travellers' diarrhoea (TD) treatment (fluoroquinolone 7%, azithromycin 4%). Incident MDR organism colonization occurred in 8 travellers (incidence density 3.5/1000 travel days; cumulative incidence 11% of trips [95% CI: 4-19%]), all ESBL-producing Escherichia coli. A higher incidence of ESBL-producing E. coli acquisition was associated with travel to Asia (36% vs 7%, P = 0.02) but not with travel to other regions, TD or use of antimicrobials. No relationship was seen between fluoroquinolone or doxycycline exposure and resistance to those antimicrobials. CONCLUSIONS: Incident colonization with MDR organisms occurs at a lower rate in this military population compared with civilian travellers, with no identified modifiable risk factors, with highest incidence of ESBL acquisition observed after South Asia travel.


Assuntos
Farmacorresistência Bacteriana Múltipla , Infecções por Enterobacteriaceae , Militares , Viagem , Adulto , Enterobacteriaceae/efeitos dos fármacos , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Masculino , Militares/estatística & dados numéricos , Fatores de Risco , beta-Lactamases
8.
Food Microbiol ; 97: 103414, 2021 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-33653513

RESUMO

Microbial contamination of sprouts commonly occurs because of the pathogens present on and in the seeds and the optimal conditions for bacteria growth provided during the germination and sprouting processes. This study examined the decontamination effect of slightly acidic electrolyzed water (SAEW), a 'generally recognized as safe' (GRAS) disinfectant, in the production process of alfalfa sprouts. SAEW with various available chlorine concentrations (ACC, 25, 35, 45 mg/L) and different pH levels (5.0, 5.7 and 6.4) was used to soak seeds for different length of time (0.5 and 6 h), after which the variations in natural Enterobacteriaceae, water absorption and seed germination (germination rate, weight and length of sprouts) were determined. The results showed that when the seeds were soaked with SAEW, albeit with different ACC (25, 35 and 45 mg/L) and pH levels (5.0, 5.7 and 6.4), a significant reduction of Enterobacteriaceae and no negative effect on sprout quality was observed. The water absorption and germination rates were also not significantly adversely affected by SAEW soaking. These findings suggest that SAEW could be used to decontaminate natural Enterobacteriaceae in the production of alfalfa sprouts, with no negative side effects on the alfalfa seeds.


Assuntos
Desinfetantes/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Medicago sativa/microbiologia , Sementes/crescimento & desenvolvimento , Água/química , Cloro/química , Cloro/farmacologia , Contagem de Colônia Microbiana , Desinfetantes/química , Eletrólise , Enterobacteriaceae/crescimento & desenvolvimento , Germinação/efeitos dos fármacos , Concentração de Íons de Hidrogênio , Medicago sativa/crescimento & desenvolvimento , Sementes/microbiologia , Verduras/crescimento & desenvolvimento , Verduras/microbiologia
9.
Int J Food Microbiol ; 345: 109154, 2021 May 02.
Artigo em Inglês | MEDLINE | ID: mdl-33735783

RESUMO

A novel killer toxin produced by yeast Metschnikowia pulcherrima was purified and added into ready to cook meatballs to enhance their microbial safety and extension of their shelf life. The agent was added into ready to cook meatballs at two different concentrations (1%-K1 and 2%-K2). The results of those two groups were compared to the control group (K0) lacking the killer toxin. Physical, chemical and microbiological analyses were carried out in meat dough and all analyses were repeated at two day intervals during 10 day-storage at +4 °C. Addition of inhibitor compound in meat dough decreased the numbers of total aerobic mesophillic bacteria, yeast and molds and lactic acid bacteria. Staphylococci/Micrococci, coliform bacteria and total psychrotrophic bacterial counts of the samples were determined as well. Results showed that all indicators of microbial deterioration were found to be higher in K1 group than K2 group, revealing that there was an inverse correlation between the concentration of killer toxin and the number of microorganisms causing spoilage. In addition to 1 log decrease in the number of microorganisms in toxin added groups, the high TBARS values of the control group also showed the effectiveness of the toxin. Toxic effect analysis results showed that the killer toxin had no toxic effect on L929 mouse fibroblast cells after 24h exposure.


Assuntos
Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Metschnikowia/metabolismo , Micotoxinas/farmacologia , Staphylococcus/efeitos dos fármacos , Animais , Bovinos , Linhagem Celular , Contagem de Colônia Microbiana , Armazenamento de Alimentos , Carne/microbiologia , Camundongos
10.
BMC Infect Dis ; 21(1): 235, 2021 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-33639886

RESUMO

BACKGROUND: This study aimed to determine the epidemiological, microbiological, and molecular characteristics of an outbreak of carbapenem-resistant Leclercia adecarboxylata in three hospitals associated with the unintended use of contaminated total parental nutrition (TPN). METHODS: For 10 days, 25 patients who received intravenous TPN from the same batch of a formula developed sepsis and had blood cultures positive for L. adecarboxylata. Antimicrobial susceptibility and carbapenemase production were performed in 31 isolates, including one from an unopened bottle of TPN. Carbapenemase-encoding genes, extended-spectrum ß-lactamase-encoding genes were screened by PCR, and plasmid profiles were determined. Horizontal transfer of carbapenem resistance was performed by solid mating. Clonal diversity was performed by pulsed-field gel electrophoresis. The resistome was explored by whole-genome sequencing on two selected strains, and comparative genomics was performed using Roary. RESULTS: All 31 isolates were resistant to aztreonam, cephalosporins, carbapenems, trimethoprim/sulfamethoxazole, and susceptible to gentamicin, tetracycline, and colistin. Lower susceptibility to levofloxacin (51.6%) and ciprofloxacin (22.6%) was observed. All the isolates were carbapenemase producers and positive for blaNDM-1, blaTEM-1B, and blaSHV-12 genes. One main lineage was detected (clone A, 83.9%; A1, 12.9%; A2, 3.2%). The blaNDM-1 gene is embedded in a Tn125-like element. Genome analysis showed genes encoding resistance for aminoglycosides, quinolones, trimethoprim, colistin, phenicols, and sulphonamides and the presence of IncFII (Yp), IncHI2, and IncHI2A incompatibility groups. Comparative genomics showed a major phylogenetic relationship among L. adecarboxylata I1 and USDA-ARS-USMARC-60222 genomes, followed by our two selected strains. CONCLUSION: We present epidemiological, microbiological, and molecular evidence of an outbreak of carbapenem-resistant L. adecarboxylata in three hospitals in western Mexico associated with the use of contaminated TPN.


Assuntos
Surtos de Doenças , Infecções por Enterobacteriaceae/etiologia , Enterobacteriaceae/metabolismo , Nutrição Parenteral Total/efeitos adversos , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Bacteriemia/epidemiologia , Bacteriemia/etiologia , Bacteriemia/microbiologia , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/isolamento & purificação , Enterobacteriáceas Resistentes a Carbapenêmicos/metabolismo , Criança , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Genoma Bacteriano/genética , Hospitais , Humanos , México/epidemiologia , Testes de Sensibilidade Microbiana , Tipagem de Sequências Multilocus , Filogenia , beta-Lactamases/genética
11.
Arch Microbiol ; 203(4): 1321-1334, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-33386421

RESUMO

Wild rats are known to carry different microorganisms and are considered a reservoir of zoonotic pathogens worldwide. The urban rats were collected from five districts of Tehran and Gram-negative bacteria (GNB) were isolated from fecal samples and were identified using classical biochemical tests. The antibiotic susceptibility patterns of isolated bacteria were determined by Kirby-Bauer disk diffusion method, the results of which were interpreted in line with CLSI guideline. The frequency of antibiotic-resistant genes was identified using multiplex-PCR. Moreover, PCR method was used to identify the frequency of Escherichia coli O157:H7 and main categories of diarrheagenic E. coli including EPEC, ETEC, EIEC, EAEC, and STEC pathotypes. A total of 100 Rattus norvegicus were trapped and fecal samples were collected. Overall, 72 fecal samples were positive for GNB. E. coli (n = 46/72) had the highest frequency among the isolated GNB. Among E. coli isolates, the highest and lowest resistance rates belonged to ampicillin (56.5%) and ceftriaxone (0%), respectively. Klebsiella spp. was 100% resistant to imipenem, and streptomycin (0%) was the most effective antimicrobial agent on Klebsiella spp. Among surveyed genes, blaTEM (95.8%) and blaaadA-1 (58.3%) had the highest frequency, while blaKPC, and blaCMY-2 were not detected among Enterobacteriaceae. Herein, O157: H7 serotype was not detected and aEPEC (87%) was the most common pathotype detected. Results suggested that rodents might be a reservoir of antimicrobial-resistant pathogens and rodent control along with implementation of surveillance programs should be considered as a critical priority for urban health.


Assuntos
Enterobacteriaceae/isolamento & purificação , Ratos/microbiologia , Animais , Animais Selvagens , Antibacterianos/farmacologia , Reservatórios de Doenças/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/classificação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Fezes/microbiologia , Irã (Geográfico) , Testes de Sensibilidade Microbiana
12.
Mol Biol Rep ; 48(1): 665-675, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33389531

RESUMO

Enterobacteriaceae spp., owing to their high durability and antibiotic-resistant mechanisms, are described as an eminent part of health treatments in hospital-acquired infections. This study aimed to estimate the prevalence of clinical isolated Enterobacteriaceae spp., and their multidrug-resistant rate in the north of Iran. In this cross-sectional study, over two years (2017-2019), clinical isolates were collected and Enterobacteriaceae spp. were identified using the standard media culture and Analytical Profile Index (API 20E) kit from two centers in the north of Iran. Isolates were confirmed by targeting the rpoB gene. Moreover, the susceptibility patterns of isolates were assessed using disc diffusion methods according to the Clinical Laboratory Standard Institute (CLSI) guidelines. Out of 2645 clinical specimens, 297 (11.2%) were confirmed as Enterobacteriaceae spp. containing Eshershia. coli 93 (31%), Citrobacter freundii 65 (21.9%), Klebsiella pneumoniae 48 (16.2%), Enterobacter spp. 43 (14.5%), and Proteus spp. 23 (7.7%). As much as 8.7% of other spp. Ampicillin (81.1%) and cephalexin (80.9%) have been shown to have the greatest resistant, and nalidixic acid (65%) and amikacin (59.2%) were the most sensitive drugs. Multidrug-resistance (MDR) strains are more isolated in the Burn and Burn intensive care unit (BICU) than other wards. The MDR frequency in Bouali and Zareh hospitals were 65 (49.61%) and 130 (78.31%), respectively. Considering the high isolation rates of MDR Enterobacteriaceae spp., preventive measures need to be taken to remove the mentioned bacteria from hospital wards.


Assuntos
Antibacterianos/efeitos adversos , Infecção Hospitalar/genética , Farmacorresistência Bacteriana Múltipla/genética , Enterobacteriaceae/genética , Antibacterianos/uso terapêutico , Infecção Hospitalar/epidemiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/prevenção & controle , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/patogenicidade , Humanos , Irã (Geográfico)/epidemiologia , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/patogenicidade , Testes de Sensibilidade Microbiana
13.
Food Chem ; 346: 128970, 2021 Jun 01.
Artigo em Inglês | MEDLINE | ID: mdl-33422919

RESUMO

Cedarwood essential oil (CEO) has the effect of anti-inflammatory and anti-bacteria. However, the application of this essential oil is limited due to its strong volatility and poor water solubility. To address this issue, two types of oil-in-water CEO emulsions including CEO nanoemulsion (CEO-NE) and CEO Pickering emulsion (CEO-PE) were prepared. CEO-NE with 5% surfactant, had a smaller particle size (135.14 ± 1.1 nm) and higher absolute zeta potential value (32.75 mV) compared with CEO-PE (1% starch) which particle size was 626.21 ± 6.05 nm, zeta potential was 27.58 mV. The stability of CEO-NE and CEO-PE were tested by multiple light scattering, results showed that Turbiscan Stability Index (TSI) value of CEO-NE was much lower than that of CEO-PE. CEO-NE and CEO-PE exerted higher free radical scavenging activities, iron reducing power and antibacterial ability than CEO itself. These results indicated that emulsification is a feasible method to extend application of CEO.


Assuntos
Antibacterianos/química , Antioxidantes/química , Emulsões/química , Óleos Voláteis/química , Antibacterianos/farmacologia , Cedrus/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Cromatografia Gasosa-Espectrometria de Massas , Tamanho da Partícula , Reologia , Resistência ao Cisalhamento , Temperatura
14.
Carbohydr Polym ; 255: 117389, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436218

RESUMO

A homogeneous polysaccharide named SHNP with apparent molecular weight of 8.4 kDa was purified from brown algae Sargassum henslowianum using ethanol precipitation, ion-exchange chromatography, and gel-filtration column chromatography. Structural analyses reveal that SHNP is completely composed of glucose, and its backbone consists of ß-D-(1→3)-Glcp with side chains comprising t-ß-D-Glcp attached at the O-6 position. Thus, SHNP is a laminarin-type polysaccharide. In vitro fermentation test results showed that SHNP was digested by gut microbiota; the pH value in the fecal culture of SHNP was significantly decreased; and total short-chain fatty acids, acetic, propionic and n-butyric acids were significantly increased. Furthermore, SHNP regulated the intestinal microbiota composition by stimulating the growth of species belonging to Enterobacteriaceae while depleting Haemophilus parainfluenzae and Gemmiger formicilis. Taken together, these results indicate that SHNP has the potential for regulating gut microbiota, but its specific role in the regulation requires to be further investigated.


Assuntos
Ácidos Graxos Voláteis/biossíntese , Microbioma Gastrointestinal/fisiologia , Glucanos/farmacologia , Prebióticos/análise , Sargassum/química , Biotransformação , Clostridiales/efeitos dos fármacos , Clostridiales/crescimento & desenvolvimento , Clostridiales/isolamento & purificação , Clostridiales/patogenicidade , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/fisiologia , Fezes/química , Fezes/microbiologia , Fermentação , Glucanos/química , Glucanos/isolamento & purificação , Glucose/química , Haemophilus parainfluenzae/efeitos dos fármacos , Haemophilus parainfluenzae/crescimento & desenvolvimento , Haemophilus parainfluenzae/isolamento & purificação , Haemophilus parainfluenzae/patogenicidade , Humanos , Concentração de Íons de Hidrogênio , Estrutura Molecular , Peso Molecular , Prebióticos/administração & dosagem
15.
PLoS One ; 16(1): e0245250, 2021.
Artigo em Inglês | MEDLINE | ID: mdl-33507909

RESUMO

This Southeast Asia-Europe research project will use a One Health approach to identify the major parameters responsible for the presence of animal-associated antimicrobial resistant bacteria in animal production facilities in Thailand and the risk of their transmission from animals to humans. We will focus on traditional, small, extensive pig and poultry farms where information on antibiotic use is scarce and animals live in close contact with humans. This cross-sectional study will be based on the epidemiological analysis of the antimicrobial resistance (AMR) present in fecal samples from animals and humans. Extended spectrum beta-lactamase producing Enterobacteriaceae (ESBL-E) and Enterobacteriaceae resistant to colistin will be actively searched in the feces of farm animals (pigs and poultry), small wild rodents and farmers. Phenotypic (selective plating) and genotypic (multilocus seuquence typing and sequencing) methods will be used for the detection of AMR, the identification of antibiotic resistance genes (ARGs) and the characterization of strains carrying resistance genes. Questionnaires will be administered to investigate the effects of antibiotic use, farm characteristics and biosecurity measures on the occurrence of AMR in animals. Subsequently, the fecal carriage of AMR and ARGs in farmers will be compared to a control population with no occupational contacts with animals, thus enabling an estimation of the risk of transmission of AMR/ARGs from animals to farmers.


Assuntos
Farmacorresistência Bacteriana , Enterobacteriaceae/isolamento & purificação , Exposição Ocupacional , Animais , Antibacterianos/farmacologia , Galinhas , Colistina/farmacologia , Estudos Transversais , DNA Bacteriano/química , DNA Bacteriano/metabolismo , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/transmissão , Fazendeiros/psicologia , Fezes/microbiologia , Humanos , Tipagem de Sequências Multilocus , Inquéritos e Questionários , Suínos , Tailândia , Sequenciamento Completo do Genoma , beta-Lactamases/genética
17.
J Appl Microbiol ; 130(5): 1721-1729, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32966644

RESUMO

AIMS: This study was designed to analyse the prevalence of class 1 and class 2 integron integrase genes among antibiotic-resistant coliform bacteria isolated from paper currency circulating in Pakistan. METHODS AND RESULTS: A total of 500 individual currency notes were collected from different food vending sites at Lahore, Pakistan. Bacterial population were identified by biochemical and PCR techniques. Antimicrobial susceptibility testing was performed by disc diffusion assay. The highest bacterial population on currency was found from street vendors and butcher shops. Escherichia coli was found to be the most prevalent coliform bacteria followed by Klebsiella sp. and Enterobacter sp. PCR amplification of antimicrobial resistance gene showed the presence of ampC, blaTEM , blaNDM-1 , qnrA, tet(A) and tet(B) genes among coliform isolates. A total of 47 integron integrase bearing strains of coliform bacteria were analysed. Sequence analysis showed the presence of dfrA1-aadA1, dfrA1, dfrA5, dfrA7, aadA1, aadA4 cassette arrays in class 1 integron and dfrA1-sat2-aadA1 in class 2 integrase genes. CONCLUSION: Circulating currency was heavily contaminated with antimicrobial-resistant coliform bacteria bearing class 1 and class 2 integron integrase genes. SIGNIFICANCE AND IMPACT OF THE STUDY: This study describes a potential threat of severe bacterial infections due to improper hand hygiene and community sanitation when dealing with the currency notes.


Assuntos
Farmacorresistência Bacteriana , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Integrases/genética , Integrons/genética , Papel , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Comércio , DNA Bacteriano , Enterobacteriaceae/efeitos dos fármacos , Higiene , Testes de Sensibilidade Microbiana , Paquistão , Reação em Cadeia da Polimerase
18.
Arch Microbiol ; 203(1): 219-231, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-32803348

RESUMO

Goldfish farming gained more attention among the ornamental fishes in aquaculture industry. The occurrence of bacterial infections and further antimicrobial treatment lead to the major crisis of antibiotic resistance in aquaculture. We have isolated diverse enterobacteriaceae groups which affect the goldfish and identified their response towards 46 antimicrobials of 15 different classes. Thirteen significant bacterial isolates such as Edwardsiella tarda, Serratia marcescens, Klebsiella aerogenes, Proteus penneri, P. hauseri, Enterobacter cloacae, E. cancerogenus, E. ludwigii, Citrobacter freundii, E. coli, Kluyvera cryocrescens, Plesiomonas shigelloides and Providencia vermicola were recovered from the infected fish with the Shannon-wiener diversity index of 2.556. Multiple antibiotic resistance (MAR) index was found to be maximum for P. penneri (0.87) and minimum for C. freundii and E. cloacae (0.22), highlighting the hyper antibiotic selection pressure in the farm. The minimum concentration of antibiotics required to inhibit most of the resistant isolates was found to be > 256 mcg/ml. All the isolates were susceptible towards ciprofloxacin. Plasmid curing and further AMR tests could reveal the location of antibiotic resistance genes mainly as plasmids which determine the large extent of AMR spread through horizontal gene transfer. This study is the first of its kind to investigate the antimicrobial resistance profile of enterobacteriaceae recovered from goldfish, before and after plasmid curing.


Assuntos
Antibacterianos/farmacologia , Infecções por Enterobacteriaceae/veterinária , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Doenças dos Peixes/microbiologia , Carpa Dourada/microbiologia , Animais , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Água Doce , Transferência Genética Horizontal/efeitos dos fármacos , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética
19.
J Appl Microbiol ; 130(5): 1523-1530, 2021 May.
Artigo em Inglês | MEDLINE | ID: mdl-32890446

RESUMO

AIM: To design and assess a novel protocol that employs isothermal titration calorimetry (ITC) for rapid detection of extended-spectrum ß-lactamase (ESBL)-producers in clinical pathogens. METHODS AND RESULTS: A total of 69 clinical Enterobacteriaceae isolates were examined in the new ESBL-ITC test by examining the heat profiles associated with enzyme hydrolysis of different substrates (imipenem, cefotaxime and clavulanic acid). The presence of ß-lactamase genes in the bacteria tested was confirmed by PCR and DNA sequencing. Comparative analysis between ESBL-ITC and conventional minimum inhibitory concentrations (MIC)/combined disk method (CDM) showed high agreement between the two assays. However, the ESBL-ITC test had a remarkable advantage of providing testing result within 1 h, in comparison to the 32-48 h required by MIC/CDM. CONCLUSIONS: The ESBL-ITC test developed in this work offers a new option for rapid and accurate detection of ESBL-producers. SIGNIFICANCE AND IMPACT OF THE STUDY: Timely detection of ESBL-producers is vital to guide the decision-making process in clinical treatment as well as in hospital-infection control. The new ESBL-ITC test provides a rapid phenotypic assay that can be further adapted for clinical diagnosis of ESBL-producing pathogens.


Assuntos
Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , beta-Lactamases/biossíntese , Antibacterianos/farmacologia , Calorimetria , Cefotaxima/farmacologia , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Humanos , Hidrólise , Imipenem/farmacologia , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Resistência beta-Lactâmica , beta-Lactamases/genética
20.
APMIS ; 129(3): 138-142, 2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33164263

RESUMO

To assess the performance of the drop test for polymyxin B resistance detection among Enterobacterales and non-fermentative gram-negative rods resistant to carbapenems. Seven hundred and fifteen carbapenem-resistant isolates were tested: 628 Enterobacterales species and 87 non-fermentative gram-negative rods. For the polymyxin drop test, concentrations range from 0.25 to 8.0 µg/mL. Broth microdilution, as gold standard, was performed using in-house-prepared panels and interpreted according to the CLSI guidelines. Results were interpreted in terms of categorical agreements and discrepancies. Accuracy for a drop of polymyxin B at 2.0, 4.0 and 8.0 was calculated as better cutoff for resistance determination. No very major error was observed among all isolates, and 95.5% of agreement was observed among Enterobacterales, particularly for Klebsiella pneumoniae. A higher accuracy (95.1%) was obtained when a single drop of polymyxin B at 4.0 µg/mL was applied. Polymyxin drop test presented >95% of categorical agreement, without very major errors, for KPC-producing K. pneumoniae isolates. An accuracy of 95.1% was obtained with a single drop at 4.0 µg/mL polymyxin B. Polymyxin B drop is an easy and feasible test and may allow a reduction on the turnaround time for polymyxin resistance detection and impacting on early implementation of accurate therapeutic interventions.


Assuntos
Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Bactérias Gram-Negativas/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Polimixina B/farmacologia , Farmacorresistência Bacteriana Múltipla , Enterobacteriaceae/classificação , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Bactérias Gram-Negativas/classificação , Bactérias Gram-Negativas/genética , Bactérias Gram-Negativas/isolamento & purificação , Humanos , Testes de Sensibilidade Microbiana
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