Your browser doesn't support javascript.
loading
Mostrar: 20 | 50 | 100
Resultados 1 - 20 de 9.258
Filtrar
1.
Int J Food Microbiol ; 344: 109109, 2021 Apr 16.
Artigo em Inglês | MEDLINE | ID: mdl-33677191

RESUMO

The objective of the present study was to characterize Salmonella enterica serovar Infantis isolated from chicken meat determining their clonal relationships with S. Infantis isolated from children with diarrhea. Fifteen meat-recovered S. Infantis were analyzed. Susceptibility levels to 14 antibacterial agents, the presence of ESBL and that of inducible plasmid-mediated AmpC (i-pAmpC) were determined by phenotypical methods. The presence of ESBL and pAmpC was confirmed by PCR, and detected ESBL-encoding genes were sequenced and their transferability tested by conjugation. The presence of gyrA mutations as well as Class 1 integrons was determined by PCR. Clonal relationships were established by REP-PCR and RAPD. In addition, 25 clinical isolates of S. Infantis were included in clonality studies. All meat-recovered S. Infantis were MDR, showing resistance to ampicillin, nitrofurans and quinolones, while none was resistant to azithromycin, ceftazidime or imipenem. ESBL (blaCTX-M-65) and i-pAmpC (blaDHA) were detected in 2 and 5 isolates respectively (in one case concomitantly), with blaCTX-M-65 being transferable through conjugation. In addition, 1 isolate presented a blaSHV gene. All isolates presented D87Y at GyrA, nalidixic acid active efflux pump and a Class 1 integron of ~1000 bp (aadA1). Clonal analysis showed that all isolates were related. Further they were identical to MDR blaCTX-M-65-producing S. Infantis isolates causing children diarrhea in Lima. The dissemination of MDR blaCTX-M-65-producing S. Infantis between marketed meat and children highlights a public health problem which needs be controlled at livestock level.


Assuntos
Proteínas de Bactérias/genética , Carne/microbiologia , Intoxicação Alimentar por Salmonella/transmissão , Salmonelose Animal/transmissão , Salmonella enterica/genética , beta-Lactamases/genética , Animais , Antibacterianos/farmacologia , Proteínas de Bactérias/metabolismo , Galinhas/microbiologia , Criança , Humanos , Integrons/genética , Plasmídeos/genética , Técnica de Amplificação ao Acaso de DNA Polimórfico , Intoxicação Alimentar por Salmonella/microbiologia , Salmonelose Animal/microbiologia , Salmonella enterica/efeitos dos fármacos , Salmonella enterica/isolamento & purificação , Sorogrupo , beta-Lactamases/metabolismo
2.
Nat Commun ; 12(1): 1852, 2021 03 25.
Artigo em Inglês | MEDLINE | ID: mdl-33767175

RESUMO

TEM-1 ß-lactamase degrades ß-lactam antibiotics with a strong preference for penicillins. Sequence reconstruction studies indicate that it evolved from ancestral enzymes that degraded a variety of ß-lactam antibiotics with moderate efficiency. This generalist to specialist conversion involved more than 100 mutational changes, but conserved fold and catalytic residues, suggesting a role for dynamics in enzyme evolution. Here, we develop a conformational dynamics computational approach to rationally mold a protein flexibility profile on the basis of a hinge-shift mechanism. By deliberately weighting and altering the conformational dynamics of a putative Precambrian ß-lactamase, we engineer enzyme specificity that mimics the modern TEM-1 ß-lactamase with only 21 amino acid replacements. Our conformational dynamics design thus re-enacts the evolutionary process and provides a rational allosteric approach for manipulating function while conserving the enzyme active site.


Assuntos
beta-Lactamases/genética , beta-Lactamases/metabolismo , Sequência de Aminoácidos/genética , Domínio Catalítico/genética , Biologia Computacional , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Evolução Molecular , Simulação de Dinâmica Molecular , Penicilinas/metabolismo , Conformação Proteica , Especificidade por Substrato
3.
J Med Microbiol ; 70(3)2021 Mar.
Artigo em Inglês | MEDLINE | ID: mdl-33739918

RESUMO

Introduction. Carbapenem resistance in Acinetobacter baumannii (A. baumannii) is an emerging global threat.Gap statement. The adaptation strategies of A. baumannii for this emergence as a nosocomial pathogen has been less studied.Aim. This prospective study analysed a sustained outbreak of carbapenem resistant Acinetobacter baumannii (CRAB) in the intensive care unit (ICU) with reference to antimicrobial resistance and virulence in the colonizing and pathogenic isolates under carbapenem stress.Results. The CRAB isolates from initial and sustained outbreak were found harbouring multiple carbapenemase genes. These genes included bla OXA-23 ,bla IMP, bla VIM and bla NDM. From NICU environment three phenotypically carbapenem susceptible isolates were found carrying bla OXA-23, bla IMP, bla VIM genes. Prior imipenem therapy was one of the risk factors (P=0.0016). The outbreak was polyclonal. Under imipenem stress, outbreak isolates showed no loss of carbapenemase genes against stress free conditions (23.7±1.33 days). Biofilm formation increased with imipenem concentration, with outbreak isolates producing highest biomass. While the pathogens showed a slow growth rate on imipenem exposure, the colonisers grew rapidly (P <0.0001).Methods. Sustained outbreak of CRAB was identified in the ICU (July 2015 to December 2017). Risk factors for acquisition of CRAB was studied. A. baumannii isolates were also collected from the environments of ICU and neonatal ICU (NICU) and blood cultures of septic neonates. Isolates were characterized based on antimicrobial susceptibility, genetic profile, integrons carriage and clonality. Biofilm formation and growth kinetics were studied under varying carbapenem stress.Conclusion. Intense carbapenem exposure in the ICU facilitates persistence of CRAB by several adaptations causing sustained outbreaks.


Assuntos
Infecções por Acinetobacter/microbiologia , Acinetobacter baumannii/fisiologia , Adaptação Fisiológica , Carbapenêmicos/farmacologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Farmacorresistência Bacteriana Múltipla/fisiologia , Infecções por Acinetobacter/tratamento farmacológico , Infecções por Acinetobacter/epidemiologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/patogenicidade , Adulto , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Biofilmes/efeitos dos fármacos , Biofilmes/crescimento & desenvolvimento , Carbapenêmicos/uso terapêutico , Infecção Hospitalar/tratamento farmacológico , Infecção Hospitalar/epidemiologia , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Microbiologia Ambiental , Feminino , Genes Bacterianos , Humanos , Imipenem/farmacologia , Imipenem/uso terapêutico , Integrons/genética , Unidades de Terapia Intensiva , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Prospectivos , Fatores de Risco , Virulência , beta-Lactamases/genética , beta-Lactamases/metabolismo
4.
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
5.
BMC Infect Dis ; 21(1): 85, 2021 Jan 19.
Artigo em Inglês | MEDLINE | ID: mdl-33468073

RESUMO

BACKGROUND: To determine the phenotype, molecular characterisation and risk factors of postoperative meningitis induced by Extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae (EPE) in China. METHODS: We performed a multi-centre comparative cohort study of postoperative meningitis patients infected with Enterobacteriaceae in 4 neurosurgical centres in China from January 2014 to December 2019. Phenotype and molecular characteristics of the isolates were reviewed and tested, and independent risk factors of the EPE meningitis were evaluated by binary logistic regression. RESULTS: In total, 220 Enterobacteriaceae include 78 EPE were available in this study. 85.6% (67/78) ESBL-related genes were tested, and blaSHV (14.9%) and blaSHV + blaTEM + blaCTX-M-9 (20.9%) were found to be the most frequent mono and combined ESBL-related genes harboured by Enterobacteriaceae. On binary logistic analysis, craniotomy (OR. 2.583, 95% C.I. 1.274-5.235, P = 0.008) and malignancy (OR. 2.406, 95% C.I. 1.299-4.456, P = 0.005) were the associated independent risk factors to meningitis induced by EPE. CONCLUSIONS: To the best of our knowledge, this is the largest series focusing on risk factors of EPE meningitis which has been conducted in China. Craniotomy and malignancy were independent risk factors for EPE meningitis. The risk factors identified may be further utilized in clinical practice and research to avoid and reduce the mortality in future.


Assuntos
Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/isolamento & purificação , Meningites Bacterianas/epidemiologia , beta-Lactamases/metabolismo , Adulto , China/epidemiologia , Estudos de Coortes , Enterobacteriaceae/genética , Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/líquido cefalorraquidiano , Infecções por Enterobacteriaceae/microbiologia , Feminino , Humanos , Masculino , Meningites Bacterianas/líquido cefalorraquidiano , Meningites Bacterianas/microbiologia , Fenótipo , Reação em Cadeia da Polimerase , Complicações Pós-Operatórias/líquido cefalorraquidiano , Complicações Pós-Operatórias/epidemiologia , Complicações Pós-Operatórias/microbiologia , Estudos Retrospectivos , Fatores de Risco
6.
Carbohydr Polym ; 255: 117484, 2021 Mar 01.
Artigo em Inglês | MEDLINE | ID: mdl-33436244

RESUMO

Wound dressing composed of chitosan, based crosslinked gelatin/ polyvinyl pyrrolidone, embedded silver nanoparticles were fabricated using solution casting method. The membrane was characterized by FTIR, SEM and TGA. Glutaraldehyde (0.5 %) was used for the crosslinking of membrane components and associated with 7-folds boosted mechanical performance, 28 % more hydrolytic stability, 3-folds thickness reduction and morphological roughness. Silver nanoparticles were characterized by UV-vis, XRD and TEM for an average size of 9.9 nm. The membrane with higher concentration of silver nanoparticles showed maximum antibacterial activity against human pathogenic bacteria; and the measured inhibition zones ranged from 1.5 to 3 cm. The activity of the particles ranged from severe to complete reduction in Penicillin, Erythromycin and Macrolide family's resistance genes expression such as ß-Lactamase, mecA and erm. This developed membrane can serve as promising and cost-effective system against severe diabetic and burn wound infections.


Assuntos
Antibacterianos/farmacologia , Bandagens , Quitosana/química , Citrullus colocynthis/química , Gelatina/química , Povidona/química , Prata/farmacologia , Bacillus subtilis/efeitos dos fármacos , Bacillus subtilis/crescimento & desenvolvimento , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana Múltipla/efeitos dos fármacos , Farmacorresistência Bacteriana Múltipla/genética , Eritromicina/farmacologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/crescimento & desenvolvimento , Fibroblastos/citologia , Fibroblastos/efeitos dos fármacos , Regulação Bacteriana da Expressão Gênica/efeitos dos fármacos , Humanos , Macrolídeos/farmacologia , Nanopartículas Metálicas/química , Nanopartículas Metálicas/ultraestrutura , Metiltransferases/genética , Metiltransferases/metabolismo , Testes de Sensibilidade Microbiana , Proteínas de Ligação às Penicilinas/genética , Proteínas de Ligação às Penicilinas/metabolismo , Penicilinas/farmacologia , Cultura Primária de Células , Pseudomonas aeruginosa/efeitos dos fármacos , Pseudomonas aeruginosa/crescimento & desenvolvimento , Salmonella typhi/efeitos dos fármacos , Salmonella typhi/crescimento & desenvolvimento , Prata/química , Staphylococcus aureus/efeitos dos fármacos , Staphylococcus aureus/crescimento & desenvolvimento , beta-Lactamases/genética , beta-Lactamases/metabolismo
7.
Arch Gynecol Obstet ; 303(2): 363-379, 2021 02.
Artigo em Inglês | MEDLINE | ID: mdl-33386957

RESUMO

PROPOSE: The aim of the present study was to determine the prevalence of E. coli and extended-spectrum ß-lactamase-producing (ESBL) E. coli in pregnant women in a systematic review and meta-analysis study. METHODS: We searched important databases, including Medline (PubMed), Embase, Scopus, Web of sciences, Cochrane library, Ovid, and CINHAL to retrieve all articles reporting the prevalence of ESBL E. coli in pregnant women that published from January 1990 to June 2020. RESULTS: The pooled prevalence of E. coli in pregnant women with and without symptoms of UTI after combining 82 studies with a sample size of 33,118 was 29% (29%; %95 CI 23, 36%). The prevalence based on urine, Feacal, and vagina samples was 26% (% 95 CI 19-34%), 77% (% 95 CI 22-98%), and 32% (% 95 CI 17-48%), respectively. Also, 19 studies with a sample size of 9,200 reported ESBL E. coli prevalence in pregnant women. After combining the results of these studies, the pooled prevalence of ESBL E. coli in pregnant women was 34% (34%; %95 CI 24, 43%). The pooled prevalence of E. coli in pregnant women with HIV was 9%(9%; %95 CI 7, 11%). CONCLUSION: According to the results of this study, the prevalence of E. coli and ESBL E. coli is high in pregnant women. Also, the overuse of antibiotics was higher in European and Asian pregnant women than other continents.


Assuntos
Infecções por Escherichia coli/epidemiologia , Escherichia coli/enzimologia , Escherichia coli/isolamento & purificação , Complicações Infecciosas na Gravidez/microbiologia , beta-Lactamases/genética , Adulto , Antibacterianos , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Humanos , Gravidez , Complicações Infecciosas na Gravidez/epidemiologia , Gestantes , Prevalência , beta-Lactamases/metabolismo
8.
Zoonoses Public Health ; 68(2): 79-87, 2021 03.
Artigo em Inglês | MEDLINE | ID: mdl-33382208

RESUMO

Animal petting zoos and farm fairs provide the opportunity for children and adults to interact with animals, but contact with animals carries a risk of exposure to zoonotic pathogens and antimicrobial-resistant bacteria. The aim of this study was to assess the occurrence of Shiga toxin-producing Escherichia coli (STEC), Salmonella, extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae and methicillin-resistant Staphylococcus aureus (MRSA) in animal faeces from six animal petting zoos and one farm fair in Switzerland. Furthermore, hygiene facilities on the venues were evaluated. Of 163 faecal samples, 75 contained stx1, stx2 or stx1/stx2 genes, indicating the presence of STEC. Samples included faeces from sika deer (100%), sheep (92%), goats (88%), mouflons (80%), camels (62%), llamas (50%), yaks (50%), pigs (29%) and donkeys (6%), whereas no stx genes were isolated from faeces of calves, guinea pigs, hens, ostriches, ponies, zebras or zebus. Salmonella enterica subsp. enterica serovar Stourbridge (S. Stourbridge) was detected in faecal samples from camels. A total of four ESBL-producing E. coli strains were isolated from faeces of goats, camels and pigs. PCR and sequencing identified the presence of blaCTX-M-15 in three and blaCTX-M-65 in one E. coli. Antimicrobial resistance profiling using the disk diffusion method revealed two multidrug-resistant (MDR) E. coli with resistance to ciprofloxacin, gentamicin and azithromycin, all of which are critically important drugs for human medicine. Multilocus sequence typing identified E. coli ST162, E. coli ST2179, extraintestinal high-risk E. coli ST410 and E. coli ST4553, which belongs to the emerging extraintestinal clonal complex (CC) 648. No MRSA was detected. On all animal petting venues, there were inadequacies with regard to access to hygiene information and handwashing hygiene facilities. This study provides data that underscore the importance of hygiene measures to minimize the risk of transmission of zoonotic pathogens and MDR, ESBL-producing E. coli to visitors of animal petting venues.


Assuntos
Criação de Animais Domésticos , Enterobacteriaceae/efeitos dos fármacos , Gado/microbiologia , Salmonella/isolamento & purificação , Escherichia coli Shiga Toxigênica/isolamento & purificação , beta-Lactamases/metabolismo , Agricultura , Animais , Animais de Zoológico , Farmacorresistência Bacteriana , Enterobacteriaceae/enzimologia , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/microbiologia , Infecções por Enterobacteriaceae/transmissão , Infecções por Enterobacteriaceae/veterinária , Regulação Enzimológica da Expressão Gênica , Genes Bacterianos , Humanos , Filogenia , Escherichia coli Shiga Toxigênica/genética , Zoonoses
9.
J Infect Public Health ; 14(1): 50-52, 2021 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-33341484

RESUMO

The impact of secondary infections by multidrug-resistant bacteria in COVID-19- infected patients has yet to be evaluated. Here, we report the clinical and molecular features of an outbreak of seven patients carrying CTX-M-15- and OXA-48-producing Klebsiella pneumoniae belonging to ST326 during COVID-19 pandemic in an ICU in northern Spain. Those patients were admitted to beds close to each other, two of them developed ventilator-associated pneumonia (VAP), one exhibited primary bacteremia and the remaining four were considered to be colonized. None of them was colonized prior to admission to the ICU an all, except one of those who developed VAP, were discharged. Hydroxychloroquine and lopinavir/ritonavir were administered to all of them as COVID-19 therapy and additionally, three of them received tocilizumab and corticosteroids, respectively. Reusing of personal protective equipment due to its initial shortage, relaxation in infection control measures and negative-pressure air in ICU rooms recommended for the protection of health care workers (HCWs), could have contributed to this outbreak. Maximization of infection control measures is essential to avoid secondary infections by MDR bacteria in COVID-infected patients.


Assuntos
/complicações , Infecção Hospitalar/diagnóstico , Infecções por Klebsiella/diagnóstico , Klebsiella pneumoniae/metabolismo , Idoso , Infecção Hospitalar/complicações , Infecção Hospitalar/tratamento farmacológico , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Unidades de Terapia Intensiva , Infecções por Klebsiella/complicações , Infecções por Klebsiella/tratamento farmacológico , Masculino , Espanha , beta-Lactamases/metabolismo
10.
Nat Commun ; 11(1): 6436, 2020 12 22.
Artigo em Inglês | MEDLINE | ID: mdl-33353963

RESUMO

In vivo mutagenesis systems accelerate directed protein evolution but often show restricted capabilities and deleterious off-site mutations on cells. To overcome these limitations, here we report an in vivo platform to diversify specific DNA segments based on protein fusions between various base deaminases (BD) and the T7 RNA polymerase (T7RNAP) that recognizes a cognate promoter oriented towards the target sequence. Transcriptional elongation of these fusions generates transitions C to T or A to G on both DNA strands and in long DNA segments. To delimit the boundaries of the diversified DNA, the catalytically dead Cas9 (dCas9) is tethered with custom-designed crRNAs as a "roadblock" for BD-T7RNAP elongation. Using this T7-targeted dCas9-limited in vivo mutagenesis (T7-DIVA) system, rapid molecular evolution of the antibiotic resistance gene TEM-1 is achieved. While the efficiency is demonstrated in E. coli, the system can be adapted to a variety of bacterial and eukaryotic hosts.


Assuntos
Aminoidrolases/metabolismo , Proteína 9 Associada à CRISPR/metabolismo , Genoma Bacteriano , Proteínas Recombinantes de Fusão/metabolismo , RNA Polimerases Dirigidas por DNA/metabolismo , Evolução Molecular Direcionada , Escherichia coli/genética , Testes de Sensibilidade Microbiana , Mutagênese/genética , Mutação/genética , RNA Guia/genética , Proteínas Virais/metabolismo , beta-Lactamases/metabolismo
11.
PLoS One ; 15(12): e0243741, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33315921

RESUMO

Rising incidence of extended- spectrum beta-lactamase (ESBL) induced urinary tract infections (UTIs) is an increasing concern worldwide. Thus, it is of paramount importance to investigate novel approaches that can facilitate the identification and guide empiric antibiotic therapy in such episodes. The study aimed to evaluate the usability of antecedent ESBL-positive urine culture to predict the pathogenic identity of future ones. Moreover, the study evaluated the accuracy of selected empiric therapy in index episodes. This was a retrospective study that included 693 cases with paired UTI episodes, linked to two separate hospital admissions within 12 month-period, and a conditional previous ESBL positive episode. Pertinent information was obtained by reviewing patients' medical records and computerized laboratory results. Multivariate analysis showed that shorter interval between index and previous episodes was significantly associated with increased chance of ESBL-positive results in current culture (OR = 0.912, 95CI% = 0.863-0.963, p = 0.001). Additionally, cases with ESBL-positive results in current culture were more likely to have underlying urological/surgical condition (OR = 1.416, 95CI% = 1.018-1.969, p = 0.039). Investigations of the accuracy of current empirical therapy revealed that male patients were less accurately treated compared to female patients (OR = 0.528, 95CI% = 0.289-0.963, p = 0.037). Furthermore, surgical patients were treated less accurately compared to those treated in internal ward (OR = 0.451, 95CI% = 0.234-0.870, p = 0.018). Selecting an agent concordant with previous microbiologic data significantly increased the accuracy of ESBL-UTIs therapy (p<0.001). A quick survey of the previous ESBL urine culture results can guide practitioners in the selection of empiric therapy for the pending current culture and thus improve treatment accuracy.


Assuntos
Bactérias/metabolismo , Infecções Urinárias/microbiologia , Infecções Urinárias/urina , beta-Lactamases/metabolismo , Adulto , Idoso , Antibacterianos/farmacologia , Antibacterianos/uso terapêutico , Bactérias/efeitos dos fármacos , Bactérias/isolamento & purificação , Farmacorresistência Bacteriana , Feminino , Hospitalização , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Estudos Retrospectivos , Infecções Urinárias/tratamento farmacológico , Infecções Urinárias/etiologia
12.
Epidemiol Infect ; 149: e12, 2020 12 17.
Artigo em Inglês | MEDLINE | ID: mdl-33327984

RESUMO

The prevalence of extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli and Klebsiella pneumoniae urinary tract infections (UTIs) is increasing worldwide. We investigated the prevalence, clinical findings, impact and risk factors of ESBL E. coli/K. pneumoniae UTI through a retrospective review of the medical records of children with UTI aged <15 years admitted to Prince of Songkla University Hospital, Thailand over 10 years (2004-2013). Thirty-seven boys and 46 girls had ESBL-positive isolates in 102 UTI episodes, compared with 85 boys and 103 girls with non-ESBL isolates in 222 UTI episodes. The age of presentation and gender were not significantly different between the two groups. The prevalence of ESBL rose between 2004 and 2008 before plateauing at around 30-40% per year, with a significant difference between first and recurrent UTI episodes of 27.3% and 46.5%, respectively (P = 0.003). Fever prior to UTI diagnosis was found in 78.4% of episodes in the non-ESBL group and 61.8% of episodes in the ESBL group (P = 0.003). Multivariate analysis indicated that children without fever (odds ratio (OR) 2.14, 95% confidence interval (CI) 1.23-3.74) and those with recurrent UTI (OR 2.67, 95% CI 1.37-5.19) were more likely to yield ESBL on culture. Congenital anomalies of the kidney and urinary tract were not linked to the presence of ESBL UTI. In conclusion, ESBL producers represented one-third of E. coli/K. pneumoniae UTI episodes but neither clinical condition nor imaging studies were predictive of ESBL infections. Recurrent UTI was the sole independent risk factor identified.


Assuntos
Infecções por Escherichia coli/microbiologia , Escherichia coli/efeitos dos fármacos , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/efeitos dos fármacos , Infecções Urinárias/microbiologia , beta-Lactamases/metabolismo , Adolescente , Antibacterianos/farmacologia , Criança , Pré-Escolar , Farmacorresistência Bacteriana Múltipla , Escherichia coli/enzimologia , Feminino , Humanos , Lactente , Klebsiella pneumoniae/enzimologia , Masculino , Estudos Retrospectivos , beta-Lactamases/genética
13.
Nat Commun ; 11(1): 5263, 2020 10 16.
Artigo em Inglês | MEDLINE | ID: mdl-33067430

RESUMO

Global emergence of Gram-negative bacteria carrying the plasmid-borne resistance genes, blaMBL and mcr, raises a significant challenge to the treatment of life-threatening infections by the antibiotics, carbapenem and colistin (COL). Here, we identify an antirheumatic drug, auranofin (AUR) as a dual inhibitor of metallo-ß-lactamases (MBLs) and mobilized colistin resistance (MCRs), two resistance enzymes that have distinct structures and substrates. We demonstrate that AUR irreversibly abrogates both enzyme activity via the displacement of Zn(II) cofactors from their active sites. We further show that AUR synergizes with antibiotics on killing a broad spectrum of carbapenem and/or COL resistant bacterial strains, and slows down the development of ß-lactam and COL resistance. Combination of AUR and COL rescues all mice infected by Escherichia coli co-expressing MCR-1 and New Delhi metallo-ß-lactamase 5 (NDM-5). Our findings provide potential therapeutic strategy to combine AUR with antibiotics for combating superbugs co-producing MBLs and MCRs.


Assuntos
Antibacterianos/administração & dosagem , Auranofina/administração & dosagem , Carbapenêmicos/farmacologia , Colistina/farmacologia , Infecções por Escherichia coli/tratamento farmacológico , Inibidores de beta-Lactamases/administração & dosagem , Animais , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/enzimologia , Escherichia coli/genética , Infecções por Escherichia coli/microbiologia , Proteínas de Escherichia coli/antagonistas & inibidores , Proteínas de Escherichia coli/genética , Proteínas de Escherichia coli/metabolismo , Feminino , Humanos , Camundongos , Camundongos Endogâmicos BALB C , Testes de Sensibilidade Microbiana , beta-Lactamases/genética , beta-Lactamases/metabolismo
14.
PLoS One ; 15(9): e0238860, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32916695

RESUMO

The presence of extended-spectrum beta-lactamase (ESBL) producing Escherichia coli on poultry products is an important issue for veterinary and human health due to the zoonotic infection risk for producers and consumers. The present study focuses on testing the efficacy of six different disinfection methods on eggshell samples, aiming to reduce ESBL producing E. coli contamination on the hatching egg. Sterile eggshell cutouts were artificially contaminated with 108 cfu/ml CTX-M-1 producing E. coli and used as a carrier model to analyze the efficacy of six disinfection methods. The contaminated samples were separated into two groups; 1) contaminated and disinfected, 2) contaminated and non-disinfected. Six independent disinfection protocols were performed following product specifications and protocols. Each eggshell sample was separately crushed, and the total viable bacterial count was calculated to determine the disinfection efficacy. Five out of six tested methods (formaldehyde gassing, hydrogen peroxide + alcohol spray, essential oils spray, peracetic acid foam, and low energetic electron radiation) demonstrated a reduction or completely eliminated the initial ESBL producing E. coli contamination. One method (essential oils as cold fog) only partly reached the expected efficacy threshold (reduction of >102 cfu/ml) and the result differed significantly when compared to the reference method i.e. formaldehyde gassing.


Assuntos
Desinfetantes/farmacologia , Desinfecção/classificação , Desinfecção/métodos , Casca de Ovo/efeitos dos fármacos , Infecções por Escherichia coli/tratamento farmacológico , Escherichia coli/enzimologia , beta-Lactamases/metabolismo , Animais , Casca de Ovo/microbiologia , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Infecções por Escherichia coli/metabolismo , Infecções por Escherichia coli/microbiologia , Humanos , Técnicas In Vitro
15.
Appl Environ Microbiol ; 86(23)2020 11 10.
Artigo em Inglês | MEDLINE | ID: mdl-32978137

RESUMO

Households provide a habitat for bacteria originating from humans, animals, foods, contaminated clothes, or other sources. Thus, bacteria carrying antibiotic resistance genes (ARGs) may be introduced via household members, animals, or the water supply from external habitats into private households and vice versa. Since data on antibiotic resistance (ABR) in the domestic environment are limited, this study aimed to determine the abundance of ß-lactamase, mobile colistin resistance, and class 1 integron genes and the correlation of their presence and to characterize phenotypically resistant strains in 54 private households in Germany. Additionally, the persistence of antibiotic-resistant bacteria during automated dishwashing compared to that during laundering was assessed. Shower drains, washing machines, and dishwashers were sampled and analyzed using quantitative real-time PCR. Resistant strains were isolated, followed by identification and antibiotic susceptibility testing using a Vitek 2 system. The results showed a significantly higher relative ARG abundance of 0.2367 ARG copies/16S rRNA gene copies in shower drains than in dishwashers (0.1329 ARG copies/16S rRNA gene copies) and washing machines (0.0006 ARG copies/16S rRNA gene copies). bla CMY-2, bla ACT/MIR, and bla OXA-48 were the most prevalent ARG, and intI1 occurred in 96.3% of the households, while no mcr genes were detected. Several ß-lactamase genes co-occurred, and the resistance of bacterial isolates correlated positively with genotypic resistance, with carbapenemase genes dominating across isolates. Antibiotic-resistant bacteria were significantly reduced during automated dishwashing as well as laundering tests and did not differ from susceptible strains. Overall, the domestic environment may represent a potential reservoir of ß-lactamase genes and ß-lactam-resistant bacteria, with shower drains being the dominant source of ABR.IMPORTANCE The abundance of antibiotic-resistant bacteria and ARGs is steadily increasing and has been comprehensively analyzed in natural environments, animals, foods, and wastewater treatment plants. In this respect, ß-lactams and colistin are of particular interest due to the emergence of multidrug-resistant Gram-negative bacteria. Despite the connection of private households to these environments, only a few studies have focused on the domestic environment so far. Therefore, the present study further investigated the occurrence of ARGs and antibiotic-resistant bacteria in shower drains, washing machines, and dishwashers. The analysis of the domestic environment as a potential reservoir of resistant bacteria is crucial to determine whether households contribute to the spread of ABR or may be a habitat where resistant bacteria from the natural environment, humans, food, or water are selected due to the use of detergents, antimicrobial products, and antibiotics. Furthermore, ABR could limit the options for the treatment of infections arising in the domestic environment.


Assuntos
Bactérias/efeitos dos fármacos , Proteínas de Bactérias/metabolismo , Farmacorresistência Bacteriana , Integrons , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Bactérias/genética , Colistina/farmacologia , Alemanha
16.
BMC Infect Dis ; 20(1): 680, 2020 Sep 17.
Artigo em Inglês | MEDLINE | ID: mdl-32942993

RESUMO

BACKGROUND: Although the risk factors for positive follow-up blood cultures (FUBCs) in gram-negative bacteremia (GNB) have not been investigated extensively, FUBC has been routinely carried out in many acute care hospitals. We attempted to identify the risk factors and develop a predictive scoring model for positive FUBC in GNB cases. METHODS: All adults with GNB in a tertiary care hospital were retrospectively identified during a 2-year period, and GNB cases were assigned to eradicable and non-eradicable groups based on whether removal of the source of infection was possible. We performed multivariate logistic analyses to identify risk factors for positive FUBC and built predictive scoring models accordingly. RESULTS: Out of 1473 GNB cases, FUBCs were carried out in 1268 cases, and the results were positive in 122 cases. In case of eradicable source of infection, we assigned points according to the coefficients from the multivariate logistic regression analysis: Extended spectrum beta-lactamase-producing microorganism (+ 1 point), catheter-related bloodstream infection (+ 1), unfavorable treatment response (+ 1), quick sequential organ failure assessment score of 2 points or more (+ 1), administration of effective antibiotics (- 1), and adequate source control (- 2). In case of non-eradicable source of infection, the assigned points were end-stage renal disease on hemodialysis (+ 1), unfavorable treatment response (+ 1), and the administration of effective antibiotics (- 2). The areas under the curves were 0.861 (95% confidence interval [95CI] 0.806-0.916) and 0.792 (95CI, 0.724-0.861), respectively. When we applied a cut-off of 0, the specificities and negative predictive values (NPVs) in the eradicable and non-eradicable sources of infection groups were 95.6/92.6% and 95.5/95.0%, respectively. CONCLUSIONS: FUBC is commonly carried out in GNB cases, but the rate of positive results is less than 10%. In our simple predictive scoring model, zero scores-which were easily achieved following the administration of effective antibiotics and/or adequate source control in both groups-had high NPVs. We expect that the model reported herein will reduce the necessity for FUBCs in GNB cases.


Assuntos
Bacteriemia/etiologia , Bacteriemia/microbiologia , Hemocultura , Infecções por Bactérias Gram-Negativas/tratamento farmacológico , Infecções por Bactérias Gram-Negativas/microbiologia , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Bacteriemia/tratamento farmacológico , Feminino , Seguimentos , Bactérias Gram-Negativas/metabolismo , Infecções por Bactérias Gram-Negativas/complicações , Humanos , Falência Renal Crônica/microbiologia , Modelos Logísticos , Masculino , Pessoa de Meia-Idade , Modelos Teóricos , Curva ROC , Estudos Retrospectivos , Fatores de Risco , Resultado do Tratamento , beta-Lactamases/metabolismo
17.
S Afr Med J ; 110(8): 783-790, 2020 Jul 29.
Artigo em Inglês | MEDLINE | ID: mdl-32880307

RESUMO

BACKGROUND: Rates of healthcare-associated infections (HAIs) among babies born in developing countries are higher than among those born in resource-rich countries, as a result of suboptimal infection prevention and control (IPC) practices. Following two reported deaths of neonates with carbapenem-resistant Klebsiella pneumoniae bloodstream infections (BSIs), we conducted an outbreak investigation in a neonatal unit of a regional hospital in Gauteng Province, South Africa. OBJECTIVES: To confirm an outbreak of K. pneumoniae BSIs and assess the IPC programme in the neonatal unit. METHODS: We calculated total and organism-specific BSI incidence risks for culture-confirmed cases in the neonatal unit for baseline and outbreak periods. We conducted a clinical record review for a subset of cases with K. pneumoniae BSI that had been reported to the investigating team by the neonatal unit. An IPC audit was performed in different areas of the neonatal unit. We confirmed species identification and antimicrobial susceptibility, and used polymerase chain reaction for confirmation of carbapenemase genes and pulsed-field gel electrophoresis (PFGE) for typing of submitted clinical isolates. RESULTS: From January 2017 to August 2018, 5 262 blood cultures were submitted, of which 11% (560/5 262) were positive. Of 560 positive blood cultures, 52% (n=292) were positive for pathogenic organisms associated with healthcare-associated BSIs. K. pneumoniae comprised the largest proportion of these cases (32%; 93/292). The total incidence risk of healthcare-associated BSI for the baseline period (January 2017 - March 2018) was 6.8 cases per 100 admissions, and that for the outbreak period (April - September 2018) was 10.1 cases per 100 admissions. The incidence risk of K. pneumoniae BSI for the baseline period was 1.6 cases per 100 admissions, compared with 5.0 cases per 100 admissions during the outbreak period. Average bed occupancy for the entire period was 118% (range 101 - 133%), that for the baseline period was 117%, and that for the outbreak period was 121%. In a subset of 12 neonates with K. pneumoniae bacteraemia, the median (interquartile range (IQR)) gestational age at birth was 27 (26 - 29) weeks, and the median (IQR) birth weight was 1 100 (880 - 1 425) g. Twelve bloodstream and 31 colonising K. pneumoniae isolates were OXA-48-positive. All isolates were genetically related by PFGE analysis (89% similarity). Inadequate IPC practices were noted, including suboptimal adherence to aseptic technique and hand hygiene (57% overall score in the neonatal intensive care unit), with poor monitoring and reporting of antimicrobial use (pharmacy score 55%). CONCLUSIONS: Overcrowding and inadequate IPC and antimicrobial stewardship contributed to a large outbreak of BSIs caused by genetically related carbapenemase-producing K. pneumoniae isolates in the neonatal unit.


Assuntos
Bacteriemia/microbiologia , Infecção Hospitalar/microbiologia , Surtos de Doenças , Unidades Hospitalares , Infecções por Klebsiella/epidemiologia , Gestão de Antimicrobianos , Bacteriemia/epidemiologia , Proteínas de Bactérias/metabolismo , Auditoria Clínica , Infecção Hospitalar/epidemiologia , Aglomeração , Humanos , Incidência , Recém-Nascido , Controle de Infecções , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/isolamento & purificação , Programas Médicos Regionais , África do Sul/epidemiologia , beta-Lactamases/metabolismo
18.
PLoS One ; 15(9): e0238747, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-32881936

RESUMO

K. pneumoniae was known as a nosocomial infection that causes human diseases. It is considered as one of the food-borne pathogens as it causes septicemia and diarrhea in humans. This study aims to characterize K. pneumoniae strains isolated from ready to eat processed meat phenotypically and genetically. Three hundred and fifty ready to eat processed meat (Luncheon-meat) samples were collected. Forty-four (12.6%) K. pneumoniae strains were isolated and bio-typed, where the majority were identified to belong to biotype B1. K1 and K2 serotypes were detected and strains were classified as hypermucoviscous K. pneumoniae (HVKP) and classic K. pneumoniae (CKP) (26 and 18 isolates, respectively). The isolates were resistant to several classes of ß-lactam antibiotics, ceftazidim and cefotaxime (95.5%), cefoxitin (93.2%), ertapenem (90.9%) and amoxicillin-clavulanic acid (86.4%). They were classified as extended spectrum ß-lactamases (ESBLs), AmpC or carbapenemase-producers phenotypically. Eighteen ß-lactamase genes were investigated by PCR. The most prominent genes were SHV (63.6%), TEM (52.2%), CTX-M15 (50%), AMPC (47.7%), CIT-M (45.5%) and VIM (43.2%). Co-detection of ß-lactam resistance genes revealed 42 gene profiles. Twenty-four isolates had the complete efflux system (AcrAB-ToƖC). Besides, Integrons (I, II, III) were detected in 20 isolates. Molecular typing by ERIC-PCR showed high genetic diversity between isolates as 34 different patterns were identified. Overall, this study confirmed the hazards posed by the presence of multiple resistance genes in the same isolate and this should not be undervalued. Besides, the horizontal transfer of plasmid harboring resistance genes between isolates in food represents potential health risks for consumers in Egypt and so the control and inhibition plans are necessary.


Assuntos
Manipulação de Alimentos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/isolamento & purificação , Carne/microbiologia , Resistência beta-Lactâmica , Antibacterianos/farmacologia , Egito , Klebsiella pneumoniae/classificação , Klebsiella pneumoniae/genética , Tipagem Molecular , Fenótipo , Resistência beta-Lactâmica/genética , beta-Lactamases/metabolismo
19.
BMC Infect Dis ; 20(1): 673, 2020 Sep 16.
Artigo em Inglês | MEDLINE | ID: mdl-32938424

RESUMO

BACKGROUND: Urinary tract infection is one of the most common bacterial infections in children. Understanding the characteristics of uropathogens and their antimicrobial susceptibility pattern in a particular setting can provide evidence for the appropriate management of cases. This study aimed to assess the bacterial profile of urinary tract infection, their antimicrobial susceptibility pattern and associated factors among clinically suspected children attending at Felege-Hiwot Comprehensive Specialized Hospital, Northwest Ethiopia. METHODS: A hospital-based cross-sectional study was conducted from February-April, 2019. A systematic sampling technique was employed. A mid-stream urine sample was inoculated on cystine lactose electrolyte deficient media and incubated for 24-48 h. Sub-culturing was done on Mac-Conkey and blood agar. Antimicrobial susceptibility test was done on Muller-Hinton agar. A binary logistic regression model was used to see the association between dependent and independent factors. A p-value< 0.05 at 95% CI was considered as statistically significant. RESULTS: The overall prevalence of urinary tract infection was 16.7% (95% CI 12.4-21.1). Both Gram-negative and Gram-positive bacterial isolates were recovered with a rate of 44/50 (88%) and 6/50 (12%) respectively. Among Gram-negative isolates, E. coli 28/44(63.6%) was predominant while S. saprophyticus 2/6(33.3%) was prevalent among Gram-positive bacterial isolates. Overall, a high level of resistance to ampicillin, augmentin, and tetracycline was shown by Gram-negative bacteria with a rate of 44/44(100%), 39/44(88.6%), and36/44 (81.8%) respectively. About 33/50(66%) of overall multidrug resistance was observed (95% CI 52-78). About six Gram-negative bacterial isolates were extended spectrum beta-lactamase (ESBL) producers. Having a history of urinary tract infection (P-0.003, AOR 1.86-22.15) and male uncircumcision (p-0.00, AOR 5.5-65.35) were the independent variables that associate for urinary tract infections. CONCLUSION: In the present study, the prevalence of urinary tract infection among children was high and considerably a high proportion of multidrug resistance was observed. This result will have a significant impact on the selection of appropriate antimicrobial agents for the treatment of urinary tract infection.


Assuntos
Infecções Urinárias/diagnóstico , Adolescente , Antibacterianos/farmacologia , Criança , Pré-Escolar , Estudos Transversais , Farmacorresistência Bacteriana Múltipla , Escherichia coli/efeitos dos fármacos , Escherichia coli/isolamento & purificação , Etiópia/epidemiologia , Feminino , Bactérias Gram-Negativas/efeitos dos fármacos , Bactérias Gram-Negativas/isolamento & purificação , Bactérias Gram-Positivas/efeitos dos fármacos , Bactérias Gram-Positivas/isolamento & purificação , Hospitais , Humanos , Lactente , Masculino , Testes de Sensibilidade Microbiana , Razão de Chances , Estudos Prospectivos , Infecções Urinárias/microbiologia , beta-Lactamases/genética , beta-Lactamases/metabolismo
20.
J Med Microbiol ; 69(10): 1235-1239, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-32924918

RESUMO

Introduction. Increased carbapenem resistance is often caused by carbapenemase production.Aim. The objective of our study was to assess which antibiotic susceptibility patterns, as tested by automated systems, are highly associated with the absence of carbapenemase production in Enterobacteriaceae isolates, and could therefore be used as a screening tool.Methodology. Routine antibiotic susceptibility testing data from 42 medical microbiology laboratories in the Netherlands in the period between January 2011 and June 2017 were obtained from the national antimicrobial resistance surveillance programme. Data on Enterobacteriaceae isolates that had an elevated minimum inhibitory concentration (MIC) for carbapenems (meropenem >0.25 mg l-1 or imipenem >1.0 mg l-1) were selected and subjected to phenotypic or genotypic carbapenemase production testing. Routinely available amoxicillin/clavulanic acid, piperacillin/tazobactam, cefuroxime and ceftriaxone/cefotaxime susceptibilities were studied in relation to carbapenemase production by calculating the negative predictive value.Results. No evidence for carbapenemase-producing Enterobacteriaceae (CPE) was found in 767 of 1007 (76 %) isolates. The negative predictive value was highest for amoxicillin/clavulanic acid (99.6 %) and piperacillin/tazobactam (98.8 %).Conclusion. Enterobacteriaceae isolates with elevated carbapenem MICs that are susceptible to amoxicillin/clavulanic acid or piperacillin/tazobactam are unlikely to be carbapenemase producers. Preselection based on this susceptibility pattern may lead to increased laboratory efficiency and reduction of costs. Whether this is also true for countries with a different distribution of CPE species and types or a higher prevalence of CPE needs to be studied.


Assuntos
Proteínas de Bactérias/metabolismo , Enterobacteriáceas Resistentes a Carbapenêmicos/metabolismo , Enterobacteriaceae/efeitos dos fármacos , beta-Lactamases/metabolismo , Antibacterianos/farmacologia , Enterobacteriáceas Resistentes a Carbapenêmicos/patogenicidade , Carbapenêmicos/farmacologia , Enterobacteriaceae/metabolismo , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/microbiologia , Humanos , Imipenem , Testes de Sensibilidade Microbiana , Países Baixos , Combinação Piperacilina e Tazobactam , beta-Lactamas/farmacologia
SELEÇÃO DE REFERÊNCIAS
DETALHE DA PESQUISA
...