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2.
Rev. Pesqui. (Univ. Fed. Estado Rio J., Online) ; 13: 17-26, jan.-dez. 2021. tab
Artigo em Inglês, Português | LILACS, BDENF - Enfermagem | ID: biblio-1145877

RESUMO

Objetivo: verificar a demanda de hemoculturas, aspirados traqueais e uroculturas realizadas no HU-UNIVASF/ EBSERH e a prevalência dos microrganismos identificados no período de janeiro a junho de 2016. Métodos: estudo retrospectivo documental com abordagem quantitativa. Resultados: o setor de microbiologia realizou 488 hemoculturas, 427 uroculturas e 197 aspirados traqueais. A positividade de hemoculturas mostrou-se entre 10,9 à 25,7%, e o percentual de contaminações variou de 6,8 à 14,0%. Os microrganismos mais prevalência nas hemoculturas foram Staphylococcus epidermidis (23,7%), Staphylococcus aureus (19,3%) e Klebisiella pneumoniae (9,6%). Nas uroculturas foram Klebisiella pneumoniae (23,1%), Candida sp. (13,5%) e Escherichia coli (12,5%). Nos aspirados traqueais foram Acinetobacter baumannii (29,2%), Pseudomonas aeruginosa (26,6%) e Staphylococcus aureus (16,2%). Conclusão: a cultura mais solicitada foi hemocultura. A bactéria mais prevalente nas hemoculturas foi Staphylococcus epidermidis, nos aspirados traqueais Acinetobacter baumannii e nas uroculturas Klebisiella pneumoniae


Objective: the study's purpose has been to verify the demand for blood cultures, tracheal aspirates and urine cultures performed at a University Hospital from the Universidade Federal do Vale do São Francisco (HU-UNIVASF/EBSERH), as well as the predominance of microorganisms identified over the period from January to June 2016. Methods: it is a retrospective documentary study with a quantitative approach. Results: the microbiology sector carried out 488 blood cultures, 427 urine cultures and 197 tracheal aspirates. The positivity of blood cultures was between 10.9 and 25.7%, and the percentage of contaminations ranged from 6.8 to 14.0%. The most prevalent microorganisms in blood cultures were Staphylococcus epidermidis (23.7%), Staphylococcus aureus (19.3%) and Klebsiella pneumoniae (9.6%). In urine cultures were Klebsiella pneumoniae (23.1%), Candida sp. (13.5%) and Escherichia coli (12.5%). In tracheal aspirates were Acinetobacter baumannii (29.2%), Pseudomonas aeruginosa (26.6%) and Staphylococcus aureus (16.2%). Conclusion: the most requested culture was blood culture. The most prevalent bacterium in blood cultures was Staphylococcus epidermidis, in tracheal aspirates was Acinetobacter baumannii, and in urine cultures was Klebsiella pneumoniae


Objetivo: el propósito del trabajo es verificar la demanda de hemocultivos, aspirados traqueales y urocultivos realizados en el Hospital Universitário de la Universidade Federal do Vale do São Francisco (HU-UNIVASF/ EBSERH) y la prevalencia de los microorganismos identificados en el período de enero a junio de 2016. Métodos: este trabajo es un estudio retrospectivo documental con abordaje cuantitativo. Resultados: el sector de microbiología realizó 488 hemocultivos, 427 urocultivos y 197 aspirados traqueales. La positividad de hemocultivos se mostró entre el 10,9 al 25,7%, y el porcentaje de contaminaciones varía de 6,8 a 14,0%. Los microorganismos más prevalentes en los hemocultivos fueron Staphylococcus epidermidis (23,7%), Staphylococcus aureus (19,3%) y Klebsiella pneumoniae (9,6%). En los urocultivos fueron Klebisiella pneumoniae (23,1%), Candida sp. (13,5%) y Escherichia coli (12,5%). En los aspirados traqueales fueron Acinetobacter baumannii (29,2%), Pseudomonas aeruginosa (26,6%) y Staphylococcus aureus (16,2%). Conclusión: la cultura más solicitada fue hemocultivo. La bacteria más prevalente en los hemocultivos fue Staphylococcus epidermidis, en los aspirados traqueales, Acinetobacter baumannii y en los urocultivos, Klebisiella pneumoniae


Assuntos
Urina/microbiologia , Infecção Hospitalar/microbiologia , Infecção Hospitalar/epidemiologia , Técnicas Bacteriológicas/métodos , Hemocultura , Staphylococcus aureus , Staphylococcus epidermidis , Prevalência , Acinetobacter baumannii , Escherichia coli , Hospitais Universitários , Klebsiella pneumoniae
3.
Water Res ; 188: 116499, 2021 Jan 01.
Artigo em Inglês | MEDLINE | ID: mdl-33049567

RESUMO

Inactivation of E. coli and Klebsiella pneumoniae by addition of H2O2 10 mg L-1 into natural well water samples containing natural total iron concentrations (around 0.3 mg L-1) under simulated solar light was followed by bacterial culturability (plate count) and viability (DVC-FISH). Results showed that culturability of both bacteria was totally reduced while viability was only completely depleted for E. coli in well water samples depending of total iron concentration. Post-irradiation effects in presence of residual H2O2 showed that viability of both bacteria kept dropping being totally reduced for E. coli cells while K. pneumoniae decreased only 1-log. SEM micrographs showed that E. coli and K. pneumoniae cells underwent morphological changes and size reduction according to VBNC states. Different dark and photo-induced processes where physical-chemical features of groundwater samples play an important role could be responsible of bacteria abatement.


Assuntos
Escherichia coli , Klebsiella pneumoniae , Desinfecção , Peróxido de Hidrogênio , Ferro , Água
4.
BMC Infect Dis ; 20(1): 936, 2020 Dec 09.
Artigo em Inglês | MEDLINE | ID: mdl-33297983

RESUMO

BACKGROUND: In spite of the evident general negative effects of armed conflict on countries' health systems and populations' health outcomes, little is known about similar impacts of conflicts on the spread of antimicrobial resistances (AMR). This review was to address this evidence gap and describe: 1. Patterns of AMR in the Middle East (ME) and resistance profiles of pathogens included in the Global AMR Surveillance System (GLASS) supported by the World Health Organization; 2. Differences in proportions of AMR isolates between conflict and non-conflict countries. METHODS: A systematic literature review was conducted following PRISMA guidelines and searching five electronic databases. Subject heading and free text were searched for "antimicrobial resistances" and "Middle East", to identify observational studies on AMR published from January 2011 to June 2018. Data were extracted from included articles on a predefined set of variables. Percentages of AMR were analysed as median and interquartile ranges. Risk of bias was assessed using the Newcastle-Ottawa Scale. RESULTS: A total of 132 articles met the inclusion criteria. Included studies showed heterogeneity in study design, laboratory methods and standards for interpretation of results, and an overall high risk of bias. Main findings were the following: 1. High proportions of carbapenem resistance in Acinetobacter spp. (median 74.2%), and both carbapenem resistance (median 8.1 and 15.4% for E. coli and K. pneumoniae respectively) and ESBL-production (median 32.3 and 27.9% for E. coli and K. pneumoniae respectively) amongst Enterobacteriaceae. S. aureus isolates showed a median methicillin resistance percentage of 45.1%, while vancomycin resistance was almost absent. A median of 50% of the strains of S. pneumoniae showed non-susceptibility to penicillin. 2. Similar trends were observed in conflict and non-conflict affected countries. CONCLUSIONS: There is a lack of standardization in the methodological approach to AMR research in the Middle East. The proportion of antibiotic resistances among specific GLASS pathogens is high, particularly among Acinetobacter spp.


Assuntos
Acinetobacter baumannii/efeitos dos fármacos , Antibacterianos/farmacologia , Carbapenêmicos/farmacologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Staphylococcus aureus Resistente à Meticilina/efeitos dos fármacos , Penicilinas/farmacologia , Humanos , Testes de Sensibilidade Microbiana , Oriente Médio , Vigilância em Saúde Pública
5.
Artigo em Inglês | PAHO-IRIS | ID: phr-53141

RESUMO

[Extract]. Antimicrobial resistance (AMR) is one of the greatest global threats to human health. It is estimated that by 2050, AMR will lead to approximately 10 million annual deaths worldwide. Considering the impact of AMR on reproductive capacity and food production, in addition to its direct effect on infected people, the world's population could drop by between 11 and 444 million inhabitants by 2050 if AMR control is not achieved. As migrations and shared economies lead to the transmission of resistant bacteria across borders, the impacts of AMR become regionally significant. In the United States, methicillin-resistant Staphylococcus aureus caused 10 600 deaths in 2017. In Latin American and Caribbean countries, information is available from studies conducted in hospitals and other health facilities on the prevalence of antimicrobial-resistant pathogens. In many hospitals in Mexico, Peru, and Colombia, for example, resistance to third-generation cephalosporins and fluoroquinolones in Escherichia coli isolates is reaching almost 60%. Moreover, the dynamics of colonization and infection of multidrug-resistant organisms (such as carbapenemaseproducing Klebsiella pneumoniae) are unique in endemic areas of Latin America, favoring spread and dissemination. [...]


Assuntos
Resistência Microbiana a Medicamentos , Resistência a Medicamentos , Medicina Baseada em Evidências , Política Informada por Evidências , Escherichia coli , Klebsiella pneumoniae
6.
Rev Soc Bras Med Trop ; 54: e02622020, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33338110

RESUMO

INTRODUCTION: Carbapenemase-resistant enterobacteria that produce the bla NDM gene are found worldwide. However, this is the first report of blaNDM in Klebsiella aerogenes in Brazil. METHODS: The identification of bacterial species was performed using anautomated system and confirmed by biochemical tests, 16S rRNA gene sequencing, and detection of resistance genes. RESULTS: The clinical isolate showed minimum inhibitory concentration resistance to meropenem and polymyxin B at 8mg/L and 4mg/L, respectively. Only the blaNDM gene was detected. CONCLUSIONS: The current report of the blaNDM gene in isolated MDR enterobacteria indicates that this gene can spread silently in a hospital setting.


Assuntos
Enterobacter aerogenes , Antibacterianos/farmacologia , Proteínas de Bactérias , Brasil , Farmacorresistência Bacteriana Múltipla/genética , Enterobacter aerogenes/genética , Enterobacteriaceae , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , RNA Ribossômico 16S , beta-Lactamases/genética
7.
BMC Infect Dis ; 20(1): 916, 2020 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-33267829

RESUMO

BACKGROUND: Klebsiella pneumoniae bloodstream infection (Kp-BSI) is a serious threat to pediatric patients. The objective of this study was to explore the risk factors, validate the prediction efficiency of pediatric Sequential Organ Failure Assessment (SOFA) and establish better early predictors of mortality in pediatric patients with Kp-BSI. METHODS: All children diagnosed with Kp-BSI were included in this retrospective cohort study from January 2009 to June 2019. Basic characteristics, symptoms and physical examinations, treatments, laboratory statistics, and SOFA at the onset of Kp-BSI were recorded. The Cox proportional hazard model and receiver operating characteristic curves were used to assess the association between the variables and the 90-day mortality and their predictive value. DeLong's test of receiver operating characteristic curves and integrated discrimination improvement index were used to determine the improvement in predictive capacity of the modified SOFA models. A predictive score was developed using multivariate logistic regression. RESULTS: Of the 146 children enrolled, 33 (22.6%) patients died within 90 days. Hospitalization in the last 6 months, intra-abdominal source of infection, presence of organ failure, and altered levels of blood biomarkers, including C-reactive protein, albumin, and lactate were significant risk factors for 90-day mortality. The area under the curve (AUC) of SOFA for predicting 90-day mortality was 0.80 (95% CI 0.71-0.89). Moreover, we found that a prediction model combining SOFA with two other parameters, namely hospitalization in the last 6 months and intra-abdominal source of infection, was better at predicting mortality (AUC = 0.89, 95% CI 0.82-0.96; sensitivity = 0.86; specificity = 0.84). According to this novel risk model, we defined three statistically different groups: low-risk, medium-risk and high-risk groups, with an observed 90-day mortality of 5.4, 35.7, and 72.0%, respectively. With reference to the low-risk patients, the medium-risk and high-risk groups had a higher mortality, with hazard ratios of 8.36 (95% CI 3.60-27.83) and 20.27 (95% CI 7.47-54.95), respectively. CONCLUSIONS: The modified SOFA may be better than the original score to predict 90-day mortality in pediatric patients with Kp-BSI. Future prospective studies are required to validate this novel scoring system in external cohorts.


Assuntos
Bacteriemia/epidemiologia , Bacteriemia/mortalidade , Infecções por Klebsiella/epidemiologia , Infecções por Klebsiella/mortalidade , Klebsiella pneumoniae/isolamento & purificação , Escores de Disfunção Orgânica , Área Sob a Curva , Biomarcadores/sangue , China/epidemiologia , Feminino , Seguimentos , Hospitalização , Humanos , Lactente , Recém-Nascido , Infecções por Klebsiella/microbiologia , Masculino , Prognóstico , Modelos de Riscos Proporcionais , Curva ROC , Estudos Retrospectivos , Fatores de Risco
8.
Sheng Wu Gong Cheng Xue Bao ; 36(9): 1899-1907, 2020 Sep 25.
Artigo em Chinês | MEDLINE | ID: mdl-33164465

RESUMO

The main purpose of this research is to synthesize and evaluate a new glycoconjugate vaccine against Klebsiella pneumonia (Kp). First, the gene (waaL) responsible for the expression of O antigen ligase was deleted to block the synthesis of bacterial LPS. Then the vector that encodes a glycosyltransferase (PglL) was transferred into the mutant. The enzyme PglL could catalyze the transfer of OPS units to recombinant cholera toxin B subunit (rCTB) to form glycoproteins in vivo. The protective effects of the glycoproteins were studied by the mice models with acute bacteremia that were induced by intraperitoneal injection of wildtype Kp bacteria. The results were as followings: A Kp waaL mutant was obtained and the rCTB protein could be successfully glycosylated in the mutant. The vaccine can stimulate a high antibody titer in the mice sera with or without adjuvant. It can also protect mice from the lethal dose injection of Kp. The survival rate of vaccine candidate groups could reach 75%. The glycoconjugate vaccine candidate prepared by this biosynthetic method is expected to become a novel effective vaccine against Klebsiella pneumoniae.


Assuntos
Anticorpos Antibacterianos , Klebsiella pneumoniae , Animais , Camundongos , Polissacarídeos , Sorogrupo , Vacinas Conjugadas
9.
BMC Infect Dis ; 20(1): 810, 2020 Nov 06.
Artigo em Inglês | MEDLINE | ID: mdl-33158426

RESUMO

PURPOSE: The purpose of this study was to explore the clinical features, risk factors, and outcomes of mixed Candida albicans/bacterial bloodstream infections (mixed-CA/B-BSIs) compared with monomicrobial Candida albicans bloodstream infection (mono-CA-BSI) in adult patients in China. METHODS: All hospitalized adults with Candida albicans bloodstream infection (CA-BSI) were recruited for this retrospective observational study from January 1, 2013, to December 31, 2018. RESULTS: Of the 117 patients with CA-BSI, 24 patients (20.5%) had mixed-CA/B-BSIs. The most common copathogens were coagulase-negative Staphylococcus (CNS) (24.0%), followed by Klebsiella pneumoniae (20.0%) and Staphylococcus aureus (16.0%). In the multivariable analysis, a prior ICU stay > 2 days (adjusted odds ratio [OR], 7.445; 95% confidence interval [CI], 1.152-48.132) was an independent risk factor for mixed-CA/B-BSIs. Compared with patients with mono-CA-BSI, patients with mixed-CA/B-BSIs had a prolonged length of mechanical ventilation [17.5 (4.5, 34.8) vs. 3.0 (0.0, 24.5), p = 0.019] and prolonged length of ICU stay [22.0 (14.3, 42.2) vs. 8.0 (0.0, 31.5), p = 0.010]; however, mortality was not significantly different. CONCLUSIONS: There was a high rate of mixed-CA/B-BSIs cases among CA-BSI cases, and CNS was the predominant coexisting species. A prior ICU stay > 2 days was an independent risk factor for mixed -CA/B-BSIs. Although there was no difference in mortality, the outcomes of patients with mixed -CA/B-BSIs, including prolonged length of mechanical ventilation and prolonged length of ICU stay, were worse than those with mono-CA-BSI; this deserves further attention from clinicians.


Assuntos
Bacteriemia/complicações , Candida albicans/isolamento & purificação , Candidíase/complicações , Infecções por Klebsiella/complicações , Klebsiella pneumoniae/isolamento & purificação , Infecções Estafilocócicas/complicações , Staphylococcus aureus/isolamento & purificação , Idoso , Bacteriemia/microbiologia , Bacteriemia/mortalidade , Candidíase/microbiologia , Candidíase/mortalidade , China/epidemiologia , Infecção Hospitalar/microbiologia , Feminino , Humanos , Estimativa de Kaplan-Meier , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/mortalidade , Masculino , Pessoa de Meia-Idade , Respiração Artificial/efeitos adversos , Estudos Retrospectivos , Fatores de Risco , Infecções Estafilocócicas/microbiologia , Infecções Estafilocócicas/mortalidade
10.
J Med Chem ; 63(22): 13669-13679, 2020 11 25.
Artigo em Inglês | MEDLINE | ID: mdl-33146528

RESUMO

Klebsiella pneumoniae is one of the most critical opportunistic pathogens. TA systems are promising drug targets because they are related to the survival of bacterial pathogens. However, structural information on TA systems in K. pneumoniae remains lacking; therefore, it is necessary to explore this information for the development of antibacterial agents. Here, we present the first crystal structure of the VapBC complex from K. pneumoniae at a resolution of 2.00 Å. We determined the toxin inhibitory mechanism of the VapB antitoxin through an Mg2+ switch, in which Mg2+ is displaced by R79 of VapB. This inhibitory mechanism of the active site is a novel finding and the first to be identified in a bacterial TA system. Furthermore, inhibitors, including peptides and small molecules, that activate the VapC toxin were discovered and investigated. These inhibitors can act as antimicrobial agents by disrupting the VapBC complex and activating VapC. Our comprehensive investigation of the K. pneumoniae VapBC system will help elucidate an unsolved conundrum in VapBC systems and develop potential antimicrobial agents.


Assuntos
Antibacterianos/farmacologia , Antitoxinas/química , Antitoxinas/farmacologia , Proteínas de Bactérias/química , Toxinas Bacterianas/química , Proteínas de Ligação a DNA/química , Klebsiella pneumoniae/química , Glicoproteínas de Membrana/química , Sistemas Toxina-Antitoxina/fisiologia , Sequência de Aminoácidos , Antibacterianos/química , Proteínas de Bactérias/antagonistas & inibidores , Proteínas de Bactérias/efeitos dos fármacos , Toxinas Bacterianas/antagonistas & inibidores , Cristalização , Proteínas de Ligação a DNA/efeitos dos fármacos , Desenvolvimento de Medicamentos/métodos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Glicoproteínas de Membrana/efeitos dos fármacos , Simulação de Acoplamento Molecular/métodos , Estrutura Secundária de Proteína , Estrutura Terciária de Proteína , Sistemas Toxina-Antitoxina/efeitos dos fármacos
11.
PLoS One ; 15(11): e0241971, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33201906

RESUMO

BACKGROUND: Fecal colonization by carbapenem-resistant Enterobacteriaceae (CRE) can be the main reservoir for transmission of these resistant organisms especially in the Intensive Care Units (ICUs). AIM: This study was conducted to evaluate the rate of rectal carriage and molecular characterization of CRE in patients hospitalized in the ICUs of 2 major hospitals (Adan and Mubarak Al Kabeer Hospitals) in Kuwait. MATERIALS AND METHODS: Rectal swabs were collected from all patients at admission, 48 h after admission and once weekly from April 2017- March 2018. Initial CRE screening was carried out on MacConkey agar on which meropenem disc 10µg was placed. Identification of isolates was by API 20E. Susceptibility testing was performed using the E-test method. Polymerase chain reaction (PCR) was used to detect the carbapenemase-encoding genes. Clonal relationship was investigated by pulsed-field electrophoresis (PFGE). Genes of blaOXA-181 and blaNDM-5-carrying plasmids were detected in some strains. RESULTS: A total of 590 patients were recruited into the study. Of these, 58 were positive for CRE, giving a prevalence of 9.8%; 25/320 (7.8%) in Adan and 33/270 (12.2%) in Mubarak Al Kabeer Hospitals. All isolates were resistant to multiple antibiotics. Resistance rates to colistin and tigecycline were 17% and 83%, respectively. Single genes of blaOXA-181 were detected in isolates from 38 (65.5%) out of 58 patients and in 5 patients colonized by blaOXA-48-positive CRE. A combination of 2 genes was detected in 12 isolates; 5 blaKPC-2 and blaOXA-181, 4 blaVIM-1 and blaOXA-181, and 3 blaNDM-5 and blaOXA-181. PFGE showed an overall level of similarity of 38%. Southern hybridization studies localized the blaOXA-181 and blaNDM-5 genes to a large plasmid of 200kb in 3 K. pneumoniae isolates and a small plasmid of 80kb in 2 E. coli isolates, respectively. CONCLUSION: The prevalence of CRE colonization in the 2 hospital ICUs was relatively high and the emergence of blaOXA-181-mediated CRE is a cause for concern as there is the possibility of rapid horizontal spread among hospital patients in Kuwait. Active surveillance of CRE in the ICUs is highly recommended to stem its spread.


Assuntos
Enterobacteriáceas Resistentes a Carbapenêmicos/crescimento & desenvolvimento , Enterobacteriáceas Resistentes a Carbapenêmicos/genética , Reto/microbiologia , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/uso terapêutico , Proteínas de Bactérias/genética , Enterobacteriáceas Resistentes a Carbapenêmicos/efeitos dos fármacos , Carbapenêmicos/uso terapêutico , Colistina/uso terapêutico , Escherichia coli/efeitos dos fármacos , Escherichia coli/genética , Escherichia coli/crescimento & desenvolvimento , Feminino , Hospitais , Humanos , Unidades de Terapia Intensiva , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/genética , Klebsiella pneumoniae/crescimento & desenvolvimento , Kuweit , Masculino , Testes de Sensibilidade Microbiana/métodos , Pessoa de Meia-Idade , Plasmídeos/genética , Prevalência , Adulto Jovem , beta-Lactamases/genética
12.
PLoS One ; 15(11): e0241595, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33206669

RESUMO

OBJECTIVES: To identify factors associated with hospital admission and mortality within the first 30 days after enrolment in an outpatient parenteral antimicrobial therapy (OPAT) program, also analysing adequacy of the treatment regimen and clinical outcomes. PATIENTS AND METHODS: This was a retrospective cohort study conducted between October 2016 and June 2017 in the state of São Paulo, Brazil. Variables related to hospital admission and mortality were subjected to bivariate analysis, and those with a P<0.05 were subjected to multivariate analysis as risk factors. RESULTS: We evaluated 276 patients, of whom 80.5% were ≥60 years of age and 69.9% had more than one comorbidity. Of the patients evaluated, 41.3% had pneumonia and 35.1% had a urinary tract infection. The most common etiological agent, isolated in 18 (31.6%) cases, was Klebsiella pneumoniae, and 13 (72,2%) strains were carbapenem resistant. The OPAT was in accordance with the culture results in 76.6% of the cases and with the institutional protocols in 76.4%. The majority (64.5%) of the patients were not admitted, and a cure or clinical improvement was achieved in 78.6%. Multivariate analysis showed that, within the first 30 days after enrolment, the absence of a physician office visit was a predictor of hospital admission (P<0.001) and mortality (P = 0.006). CONCLUSIONS: This study demonstrated the viability of OPAT in elderly patients with pulmonary or urinary tract infections in an area with a high prevalence of multidrug-resistant bacteria and that a post-discharge physician office visit is protective against hospital admission and mortality.


Assuntos
Antibacterianos/uso terapêutico , Carbapenêmicos/uso terapêutico , Pacientes Ambulatoriais/estatística & dados numéricos , Pneumonia/tratamento farmacológico , Infecções Urinárias/tratamento farmacológico , Administração Oral , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/administração & dosagem , Brasil , Carbapenêmicos/administração & dosagem , Farmacorresistência Bacteriana Múltipla , Feminino , Humanos , Klebsiella pneumoniae/efeitos dos fármacos , Klebsiella pneumoniae/patogenicidade , Masculino , Pessoa de Meia-Idade , Mortalidade/tendências , Admissão do Paciente/estatística & dados numéricos , Pneumonia/epidemiologia , Pneumonia/microbiologia , Pneumonia/mortalidade , Prevalência , Resultado do Tratamento , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Infecções Urinárias/mortalidade
13.
New Microbiol ; 43(4): 186-190, 2020 Oct.
Artigo em Inglês | MEDLINE | ID: mdl-33135084

RESUMO

The establishment of gut microbiota is reportedly aberrant in newborns admitted to neonatal intensive care units (NICUs), with detrimental long-term health impacts. Here, we vertically tracked the developing gut bacterial communities of newborns hosted in an NICU during an outbreak sustained by ESBL Klebsiella pneumoniae and compared colonized and non-colonized patients. Most communities were highly variable from one sampling point to the next, and dominated by few taxa, often Proteobacteria and Enterobacteriaceae, with marked interindividual variability. This picture was retrieved independently of colonization status or clinical covariates. Our data support the emerging idea of preterm infants as a population in which no defined microbial signatures are clearly associated to clinical status. Instead, the strong pressure of the nosocomial environment, antibiotics and, in this case, the ongoing outbreak, possibly drive the evolution of microbiota patterns according to individual conditions, also in non-colonized patients.


Assuntos
Infecção Hospitalar , Microbioma Gastrointestinal , Infecções por Klebsiella , Infecção Hospitalar/epidemiologia , Surtos de Doenças , Humanos , Recém-Nascido , Recém-Nascido Prematuro , Unidades de Terapia Intensiva Neonatal , Infecções por Klebsiella/epidemiologia , Klebsiella pneumoniae/enzimologia , Klebsiella pneumoniae/genética , beta-Lactamases/genética
14.
Int J Nanomedicine ; 15: 8295-8310, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33149577

RESUMO

Purpose: In this study, silver nanoparticles (AgNPs) were biosynthesized using culture supernatant of strain Shewanella sp. ARY1, characterized and their antibacterial activity was investigated against Gram-negative bacteria Escherichia coli and Klebsiella pneumoniae. Methods: The strain Shewanella sp. ARY1 was isolated from river Yamuna, Delhi and used for biosynthesis of AgNPs via extracellular approach. Biosynthesized AgNPs were characterized by UV-Visible (UV-Vis) spectrophotometer, fourier transform infrared (FTIR) spectroscopy, X-ray diffraction (XRD), energy dispersive X-ray (EDX), transmission electron microscopy (TEM) and scanning electron microscopy (SEM). Antibacterial activity of AgNPs was determined by well diffusion, broth microdilution and streaking plate assay to determine the zone of inhibition (ZOI), minimum inhibitory concentration (MIC) and minimum bactericidal concentration (MBC), respectively. The effect of AgNPs on treated bacteria was investigated by electron microscopy analysis. Further, the biocompatibility of AgNPs was tested against mice erythrocytes (RBC) by hemolytic assay. Results: The UV-Vis spectral analysis revealed absorption maxima at 450 nm which confirmed the formation of AgNPs. The FTIR analysis suggested the involvement of various supernatant biomolecules, as reducing and capping agents in the synthesis of AgNPs. The XRD and EDX analysis confirmed the crystalline and metallic nature of AgNPs, respectively. The TEM and SEM analysis showed nanoparticles were spherical with an average size of 38 nm. The biosynthesized AgNPs inhibited the growth and formed a clear zone of inhibition (ZOI) against tested Gram-negative strains. The MIC and MBC were determined as 8-16 µg/mL and 32 µg/mL, respectively. Further, electron microscopy analysis of treated cells showed that AgNPs can damage the outer membrane, release of cytoplasmic contents, and alter the normal morphology of Gram-negative bacteria, leading to cell death. The hemolytic assay indicated that the biosynthesized AgNPs were biocompatible at low dose concentrations. Conclusion: This study demonstrates an eco-friendly process for extracellular synthesis of AgNPs using Shewanella sp. ARY1 and these AgNPs exhibited excellent antibacterial activity, which may be used to combat Gram-negative pathogens.


Assuntos
Antibacterianos/farmacologia , Nanopartículas Metálicas/química , Shewanella/metabolismo , Prata/química , Animais , Antibacterianos/química , Eritrócitos/efeitos dos fármacos , Escherichia coli/efeitos dos fármacos , Hemólise/efeitos dos fármacos , Klebsiella pneumoniae/efeitos dos fármacos , Camundongos , Testes de Sensibilidade Microbiana , Microscopia Eletrônica de Varredura , Microscopia Eletrônica de Transmissão , Prata/farmacologia , Espectrometria por Raios X , Espectroscopia de Infravermelho com Transformada de Fourier , Difração de Raios X
15.
Proc Natl Acad Sci U S A ; 117(44): 27620-27626, 2020 11 03.
Artigo em Inglês | MEDLINE | ID: mdl-33087568

RESUMO

The extracellular polysaccharide capsule of Klebsiella pneumoniae resists penetration by antimicrobials and protects the bacteria from the innate immune system. Host antimicrobial peptides are inactivated by the capsule as it impedes their penetration to the bacterial membrane. While the capsule sequesters most peptides, a few antimicrobial peptides have been identified that retain activity against encapsulated K. pneumoniae, suggesting that this bacterial defense can be overcome. However, it is unclear what factors allow peptides to avoid capsule inhibition. To address this, we created a peptide analog with strong antimicrobial activity toward several K. pneumoniae strains from a previously inactive peptide. We characterized the effects of these two peptides on K. pneumoniae, along with their physical interactions with K. pneumoniae capsule. Both peptides disrupted bacterial cell membranes, but only the active peptide displayed this activity against capsulated K. pneumoniae Unexpectedly, the active peptide showed no decrease in capsule binding, but did lose secondary structure in a capsule-dependent fashion compared with the inactive parent peptide. We found that these characteristics are associated with capsule-peptide aggregation, leading to disruption of the K. pneumoniae capsule. Our findings reveal a potential mechanism for disrupting the protective barrier that K. pneumoniae uses to avoid the immune system and last-resort antibiotics.


Assuntos
Antibacterianos/farmacologia , Peptídeos Catiônicos Antimicrobianos/farmacologia , Cápsulas Bacterianas/efeitos dos fármacos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae/efeitos dos fármacos , Animais , Antibacterianos/uso terapêutico , Peptídeos Catiônicos Antimicrobianos/imunologia , Peptídeos Catiônicos Antimicrobianos/uso terapêutico , Cápsulas Bacterianas/metabolismo , Permeabilidade da Membrana Celular/efeitos dos fármacos , Modelos Animais de Doenças , Farmacorresistência Bacteriana Múltipla , Feminino , Células HEK293 , Interações Hospedeiro-Patógeno/imunologia , Humanos , Imunidade Inata , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/citologia , Camundongos , Testes de Sensibilidade Microbiana , Polissacarídeos Bacterianos/metabolismo
16.
Mikrobiyol Bul ; 54(4): 606-612, 2020 Oct.
Artigo em Turco | MEDLINE | ID: mdl-33107289

RESUMO

A rapid and reliable method for antimicrobial susceptibility test of colistin is needed because of increasing numbers of multi-resistant gram negative bacterial infections and simultaneus increasing of colistin resistance. Although broth microdilution (BMD) is recommended by the Clinical and Laboratory Standards Institute (CLSI) and the European Committee for Antimicrobial Susceptibility Testing (EUCAST) as a reference method, the use in routine laboratory practice is limited because of the difficulties in application and time-consuming characteristics. Recently, many BMD based commercial products were developed. The study was aimed to compare the results of the two commercial systems available for the detection of colistin sensitivity with the reference method. Totally 38 Klebsiella pneumoniae strains isolated from various clinical specimens between 2017-2018 were included in our study. Identification and antibiotic susceptibility tests were performed with "matrix-assisted laser desorption/ionization timeof-flight, mass spectrometry (MALDI-TOF MS)" and Vitek-2 (bioMérieux, Marcyl'Etoile, France) systems. BMD tests were performed with Sensititre (Sensititre custom plate, Thermo Fisher Scientific, UK) and Micronaut MIC-Strip (Merlin Diagnostika GmbH, Germany) kits. Commercial BMD assays containing dehydrated colistin in the concentration range of 0.0625-128 mg/L were tested with 0.5 McFarland bacterial suspensions prepared according to the manufacturer recommendations. The reference BMD test was performed by following the recommendations of the International Organization for Standardization (ISO-20776-1). ATCC 25922 colistin-susceptible Escherichia coli and NCTC 13846 (mcr-1 positive) colistin-resistant E.coli strains were used as the quality control strains. According to the recommendations of EUCAST version 9.0, strains with minimum inhibitory concentration value of ≤ 2 mg/L were considered susceptible and strains > 2 mg/L as resistant. Thirty-five isolates were resistant to colistin by the reference method and three of them were susceptible. The Sensititre kit detected a very major error (2.8%) in one isolate; no major or very major errors were detected for the Micronaut kit. The essential and categorical agreement of the Sensititre and Micronaut kits with the reference method was defined as 74-76% and 97-100%, respectively. Colistin is the last agent for the treatment of the multi drug resistant severe bacterial infections so major and very major error for colistin should be considered equally serious. Although a very major error was detected by the Sensititre kit in one isolate, the categorical agreement of both commercial kits was greater than 90% when compared with the reference method. It was concluded that, commercially available, BMD based systems that do not require additional equipment and experience can be routinely used.


Assuntos
Klebsiella pneumoniae , Antibacterianos/farmacologia , Colistina/farmacologia , Alemanha , Técnicas de Diluição do Indicador , Testes de Sensibilidade Microbiana
17.
Trop Anim Health Prod ; 52(6): 3923-3929, 2020 Nov.
Artigo em Inglês | MEDLINE | ID: mdl-33025455

RESUMO

In the present study, sudden mortalities were reported due to pneumonia in four neonatal camels (5 to 10 days old) of an organized dromedary camel farm. The clinical manifestations in affected camels were weakness, mild to high fever, not suckling, respiratory distress, and sudden death. On the basis of gross and histopathological lesions, the pneumonia was classified into bronchopneumonia (n = 2), bronchointerstitial pneumonia (n = 1), and interstitial pneumonia (n = 1). In bacterial culture, Klebsiella pneumoniae was isolated from lung of all the four cases. These bacteria were also confirmed by PCR from DNA isolated from culture as well as lung tissue. The sequencing of PCR products from four isolates of K. pneumoniae revealed homology with other pathogenic K. pneumoniae isolates from India and other countries. These findings confirmed the role of K. pneumoniae as an important etiological agent for causing pneumonia with sudden mortalities in suckling neonatal dromedary camels.


Assuntos
Camelus , Infecções por Klebsiella/veterinária , Klebsiella pneumoniae/isolamento & purificação , Pneumonia/veterinária , Animais , Animais Recém-Nascidos , Humanos , Índia , Infecções por Klebsiella/microbiologia , Infecções por Klebsiella/patologia , Klebsiella pneumoniae/genética , Pneumonia/microbiologia , Pneumonia/patologia
18.
Rev Soc Bras Med Trop ; 53: e20200397, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33111914

RESUMO

INTRODUCTION: Antibiotic resistance in carbapenemase-producing Klebsiella pneumoniae is acquired and disseminated mainly by plasmids. Therefore, we aimed to investigate the occurrence of carbapenemase genes, analyze the genetic diversity by ERIC-PCR, and examine the most common plasmid incompatibility groups (Incs) in clinical isolates of K. pneumoniae from colonization and infection in patients from a hospital in Brazil. METHODS: Twenty-seven isolates of carbapenem-resistant K. pneumoniae were selected and screened for the presence of carbapenemase genes and Incs by PCR, followed by amplicon sequencing. RESULTS: The bla KPC and bla NDM genes were detected in 24 (88.8 %) and 16 (59.2 %) of the isolates, respectively. Thirteen isolates (48.1 %) were positive for both genes. The IncFIB (92.6 %) and IncQ (88.8 %) were the most frequent plasmids, followed by IncA/C, IncHI1B, and IncL/M, indicating that plasmid variability existed in these isolates. To our knowledge, this is the first report of IncHI1B in Brazil. We found eight isolates with clonal relationship distributed in different sectors of the hospital. CONCLUSIONS: The accumulation of resistance determinants, the variability of plasmid Incs, and the clonal dissemination detected in K. pneumoniae isolates demonstrate their potential for infection, colonization, and the dissemination of different resistance genes and plasmids.


Assuntos
Infecções por Klebsiella , Klebsiella pneumoniae , Antibacterianos/farmacologia , Proteínas de Bactérias/genética , Brasil , Hospitais Públicos , Humanos , Klebsiella pneumoniae/genética , Testes de Sensibilidade Microbiana , Plasmídeos/genética , beta-Lactamases/genética
19.
Rev Soc Bras Med Trop ; 53: e20200032, 2020.
Artigo em Inglês | MEDLINE | ID: mdl-33027413

RESUMO

INTRODUCTION: Essential oils can serve as novel sources of antibiotics for multidrug-resistant bacteria. METHODS: The multidrug-resistance profile of a Klebsiella aerogenes strain was assessed by PCR and sequencing. The antibacterial activity of Cinnamomum cassia essential oil (CCeo) against K. aerogenes was assessed by broth microdilution and time-kill methods. RESULTS: K. aerogenes showed high antibiotic resistance. The genes bla KPC-2, ampC, bla CTX-M-15, bla OXA-1, and bla TEM were present. CCeo exhibited an inhibitory effect with a minimum inhibitory concentration of 17.57 µg/mL. CONCLUSIONS: The antibacterial activity of CCeo makes it a potential candidate for treating carbapenem- and polymyxin-resistant K. aerogenes strains.


Assuntos
Antibacterianos/uso terapêutico , Cinnamomum aromaticum , Enterobacter aerogenes , Infecções por Klebsiella , Carbapenêmicos , Humanos , Infecções por Klebsiella/tratamento farmacológico , Klebsiella pneumoniae , Óleos Voláteis , Polimixinas , beta-Lactamases
20.
Sci Rep ; 10(1): 16778, 2020 10 08.
Artigo em Inglês | MEDLINE | ID: mdl-33033293

RESUMO

Carbapenemase-producing Klebsiella pneumoniae emerged as a nosocomial pathogen causing morbidity and mortality in patients. For infection prevention it is important to track the spread of K. pneumoniae and its plasmids between patients. Therefore, the major aim was to recapitulate the contents and diversity of the plasmids of genetically related K. pneumoniae strains harboring the beta-lactamase gene blaKPC-2 or blaKPC-3 to determine their dissemination in the Netherlands and the former Dutch Caribbean islands from 2014 to 2019. Next-generation sequencing was combined with long-read third-generation sequencing to reconstruct 22 plasmids. wgMLST revealed five genetic clusters comprised of K. pneumoniae blaKPC-2 isolates and four clusters consisted of blaKPC-3 isolates. KpnCluster-019 blaKPC-2 isolates were found both in the Netherlands and the Caribbean islands, while blaKPC-3 cluster isolates only in the Netherlands. Each K. pneumoniae blaKPC-2 or blaKPC-3 cluster was characterized by a distinct resistome and plasmidome. However, the large and medium plasmids contained a variety of antibiotic resistance genes, conjugation machinery, cation transport systems, transposons, toxin/antitoxins, insertion sequences and prophage-related elements. The small plasmids carried genes implicated in virulence. Thus, implementing long-read plasmid sequencing analysis for K. pneumoniae surveillance provided important insights in the transmission of a KpnCluster-019 blaKPC-2 strain between the Netherlands and the Caribbean.


Assuntos
DNA Bacteriano/genética , Infecções por Klebsiella/microbiologia , Klebsiella pneumoniae/genética , beta-Lactamases/genética , Sequenciamento de Nucleotídeos em Larga Escala , Humanos , Klebsiella pneumoniae/isolamento & purificação , Países Baixos
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