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1.
Environ Monit Assess ; 191(8): 516, 2019 Jul 27.
Artigo em Inglês | MEDLINE | ID: mdl-31350602

RESUMO

In this study, the concentrations of nine typical antibiotics, including sulfadiazine (SD), sulfamerazine (SMR), sulfamethazine (SM2), sulfamethoxazole (SMZ), ofloxacin (OFX), ciprofloxacin (CIP), trimethoprim (TMP), oxytetracycline (OTC), and tetracycline hydrochloride (TC), were detected in the Yitong River by solid-phase extraction high-performance liquid chromatography. The concentrations of the antibiotics were analyzed. Additionally, an improved immobilized substrate enzyme substrate method (DST-enzyme substrate method) was developed and used to evaluate the antibiotic resistance of coliform bacteria to OFX, CIP, enrofloxacin (ENR), TC, sulfisoxazole (SOX), and TMP in the Yitong River. The results showed that the concentrations of the nine antibiotics ranged from nd (not detected) to 1.361 µg/L. The detection rate and concentration of OFX were the highest, followed by CIP, and the detection rate and concentration of SM2 and OTC were the lowest. The detection rate and concentrations of antibiotics were higher in August and November than those in May. The antibiotics were mainly distributed in the livestock sewage discharge and suburban domestic sewage discharge areas. Moreover, the drug resistance of total coliform bacteria to fluoroquinolones, sulfonamides, tetracyclines, and TMP varied with season.


Assuntos
Antibacterianos/análise , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Monitoramento Ambiental/métodos , Rios/química , Poluentes Químicos da Água/análise , China , Enterobacteriaceae/genética
2.
Emerg Microbes Infect ; 8(1): 857-865, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31169081

RESUMO

Ciprofloxacin resistance in Salmonella has been increasingly reported due to the emergence and dissemination of multiple Plasmid-Mediated Quinolone Resistance (PMQR) determinants, which are mainly located in non-conjugative plasmids or chromosome. In this study, we aimed to depict the molecular mechanisms underlying the rare phenomenon of horizontal transfer of ciprofloxacin resistance phenotype in Salmonella by conjugation experiments, S1-PFGE and complete plasmid sequencing. Two types of non-conjugative plasmids, namely an IncX1 type carrying a qnrS1 gene, and an IncH1 plasmid carrying the oqxAB-qnrS gene, both ciprofloxacin resistance determinants in Salmonella, were recovered from two Salmonella strains. Importantly, these non-conjugative plasmids could be fused with a novel Incl1 type conjugative helper plasmid, which could target insertion sequence (IS) elements located in the non-conjugative, ciprofloxacin-resistance-encoding plasmid through replicative transcription, eventually forming a hybrid conjugative plasmid transmissible among members of Enterobacteriaceae. Since our data showed that such conjugative helper plasmids are commonly detectable among clinical Salmonella strains, particularly S. Typhimurium, fusion events leading to generation and enhanced dissemination of conjugative ciprofloxacin resistance-encoding plasmids in Salmonella are expected to result in a sharp increase in the incidence of resistance to fluoroquinolone, the key choice for treating life-threatening Salmonella infections, thereby posing a serious public health threat.


Assuntos
Antibacterianos/farmacologia , Ciprofloxacino/farmacologia , Conjugação Genética , Farmacorresistência Bacteriana , Plasmídeos/genética , Salmonella/efeitos dos fármacos , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , DNA Bacteriano/genética , DNA Bacteriano/metabolismo , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/metabolismo , Humanos , Testes de Sensibilidade Microbiana , Plasmídeos/metabolismo , Salmonella/genética , Salmonella/metabolismo , Infecções por Salmonella/microbiologia
3.
BMC Infect Dis ; 19(1): 508, 2019 Jun 10.
Artigo em Inglês | MEDLINE | ID: mdl-31182038

RESUMO

BACKGROUND: In China multidrug-resistant bacteria pose a considerable threat to public health. Antimicrobial resistance has weakened the effectiveness of many medicines widely used today. Thus, discovering new antibacterial drugs is paramount in the effort to treat emerging drug-resistant bacteria. METHODS: Eravacycline, tigecycline and other clinical routine antibiotics were tested by reference broth micro-dilution method against 336 different strains collected from 11 teaching hospitals in China between 2012 and 2016. These isolates included Enterobacteriaceae, non-fermentative, Staphylococcus spp., Enterococcus, and a number of fastidious organisms. The strains involved in this study possess the most important drug resistance characteristics currently known in China. Drug resistant bacteria such as those producing extended spectrum ß-lactamases (ESBL) and carbapenemases (KPC-2 and NDM-1), and those exhibiting colistin resistance (mcr-1) and tigecycline were included in this study. Additionally, methicillin-resistant Staphylococcus aureus (MRSA), vancomycin-resistant enterococci (VRE), ß-lactamase positive Haemophilus influenzae, and penicillin resistant Streptococcus pneumoniae (PRSP) were also included. RESULTS: Eravacycline exhibited good efficacy against all the strains tested, especially for organisms with ESBLs, carbapenemases, and mcr-1 gene compared with tigecycline and other antibiotics tested. The MIC values of eravacycline against carbapenemase producing Enterobacteriaceae and OXA-23-producing A. baumannii were much lower than the MIC values of other antibiotics. MRSA, VRE, ß-lactamase positive Haemophilus influenza, and PRSP were sensitive to eravacycline in every strain tested. Furthermore, in most strains tested, the MICs of eravacycline were two to four-fold lower than the MICs of tigecycline. CONCLUSIONS: Eravacycline has shown potent antibacterial activity against common and clinically important antibiotic-resistant pathogens. The MIC distribution of eravacycline was generally lower than that of tigecycline which demonstrates that this new drug is potentially more effective than the existing medications.


Assuntos
Acinetobacter baumannii/isolamento & purificação , Antibacterianos/farmacologia , Enterobacteriaceae/isolamento & purificação , Tetraciclinas/farmacologia , Acinetobacter baumannii/efeitos dos fármacos , Acinetobacter baumannii/enzimologia , Proteínas de Bactérias/metabolismo , China , Farmacorresistência Bacteriana/efeitos dos fármacos , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/enzimologia , Hospitais de Ensino , Humanos , Testes de Sensibilidade Microbiana , beta-Lactamases/metabolismo
4.
J Med Microbiol ; 68(8): 1189-1193, 2019 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-31225790

RESUMO

PURPOSE: In an increasing number of cases the last therapeutic option for treatment of carbapenem-resistant Enterobacteriaceae is colistin. As the detection of colistin resistance is problematic and time-consuming, it is desirable to find a rapid and reliable test. The rapid polymyxin NP test developed by Nordmann et al. addresses this problem and has a sensitivity of 99.3  % and a specificity of 95.4  %, as described by the authors. METHODS: In this study, we aimed to evaluate the NP test and tested the effect of measuring the absorbance of the test with an enzyme-linked immunosorbent assay (ELISA) reader at 430 nm as an alternative objectified readout. We performed a study with 120 carbapenemase-producing Enterobacteriaceae isolates, including 40 colistin-resistant and 23 colistin-susceptible Klebsiella pneumoniae, 4 resistant and 23 susceptible Escherichia coli, and 20 susceptible and 10 resistant Enterobacter species, respectively. RESULTS: Our data showed lower values for sensitivity and specificity than previously, namely only 91  % and 70 %, respectively, due to visual inspection. Furthermore, the results revealed a weakness in the correct detection of colistin-susceptible Enterobacter species. With the measurement of the absorbance we optimized the results to prevent misinterpretations of weak or inconclusive colour changes and enhanced the accuracy and objectivity of the rapid polymyxin NP test results. CONCLUSION: We reinforced the rapid polymyxin NP test as a rapid and valuable tool for detecting colistin-resistant K. pneumoniae isolates, although false-positive results were obtained for several colistin-susceptible Enterobacter spp. By using the optimized method, we were able to increase the sensitivity and specificity values to 94  % and 95  %, respectively.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos dos fármacos , Testes de Sensibilidade Microbiana/métodos , Polimixinas/farmacologia , Proteínas de Bactérias/metabolismo , Enterobacteriaceae/isolamento & purificação , Enterobacteriaceae/metabolismo , Infecções por Enterobacteriaceae/microbiologia , Ensaio de Imunoadsorção Enzimática , Humanos , Sensibilidade e Especificidade , beta-Lactamases/metabolismo
5.
Ann Lab Med ; 39(5): 470-477, 2019 Sep.
Artigo em Inglês | MEDLINE | ID: mdl-31037866

RESUMO

BACKGROUND: The emergence of carbapenem resistance among gram-negative bacilli (GNB), mediated by carbapenemase production, has necessitated the development of a simple and accurate device for detecting minimum inhibitory concentrations (MICs) and resistance mechanisms, especially carbapenemase production. We evaluated the performance of the BD Phoenix NMIC-500 panel (BD Diagnostic Systems, Sparks, MD, USA) for antimicrobial susceptibility testing (AST) and carbapenemase-producing organism (CPO) detection. METHODS: We used 450 non-duplicate clinical GNB isolates from six general hospitals in Korea (409 Enterobacteriaceae and 41 glucose non-fermenting bacilli [GNFB] isolates). AST for meropenem, imipenem, ertapenem, ceftazidime, and ceftazidime/avibactam, and CPO detection were performed using the Phoenix NMIC-500 panel. Broth microdilution was used as the reference method for AST. The rates of categorical agreement (CA), essential agreement (EA), minor error (mE), major error (ME), and very major error (VME) were calculated in each antimicrobial. In addition, PCR and sequencing were performed to evaluate the accuracy of CPO detection by the BD Phoenix NMIC-500 panel, and the rate of correct identification was calculated. RESULTS: The CA rates were >90% for all antimicrobials tested with the Enterobacteriaceae isolates, except for imipenem (87.2%). The GNFB CA rates ranged from 92.7% to 100% for all antimicrobials. The ME rates were 1.7% for Enterobacteriaceae and 0% for GNFB. The panel identified 97.2% (243/250) of the carbapenemase-producing isolates. CONCLUSIONS: The BD Phoenix NMIC-500 panel shows promise for AST and CPO detection.


Assuntos
Bactérias Gram-Negativas/isolamento & purificação , Testes de Sensibilidade Microbiana/métodos , Antibacterianos/farmacologia , Bacillus/efeitos dos fármacos , Bacillus/isolamento & purificação , Proteínas de Bactérias/genética , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , beta-Lactamases/genética
6.
Environ Sci Pollut Res Int ; 26(18): 18730-18738, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-31055749

RESUMO

The extensive use of antibiotics has resulted in the development of antibiotic-resistant bacteria (ARB), which may not be completely removed by traditional wastewater treatment processes. More effective approaches to disinfection are needed to prevent the release of ARB into the surface water. The metal-free photocatalyst graphitic carbon nitride (g-C3N4) has aroused great interest as a possible agent for water and wastewater treatment, due to its low cytotoxicity and photoactivity with visible light. In this study, the efficacy of g-C3N4 was assessed as a possible means to enhance ARB inactivation by irradiation. ARB were isolated and purified from secondary effluents in 4 municipal wastewater treatment plants. Of these, 4 typical multi-drug ARB isolates, belonging to Enterobacteriaceae, were selected for irradiation experiments. Inactivation was seen to increase with irradiation time. At 60 min, the inactivation of the 4 ARB isolates by light at > 300 nm and > 400 nm was in the range of 0.25-0.39 log and 0.16-0.19 log, respectively. The use of g-C3N4-mediated photocatalysis at the same wavelengths significantly enhanced that to 0.64-1.26 log and 0.31-0.41 log, respectively. The antibiotic susceptibility of the ARB isolates remained unchanged either prior to or after irradiation and was independent of photon fluence, reaction time, and the presence of g-C3N4. This study establishes a baseline for understanding the effectiveness of g-C3N4 photocatalysis on inactivation of ARB in wastewaters and lays the foundation for further improvement in the use of photocatalysis for wastewater treatment.


Assuntos
Desinfecção/métodos , Farmacorresistência Bacteriana , Enterobacteriaceae/efeitos da radiação , Grafite/química , Luz , Nitrilos/química , Antibacterianos/farmacologia , Catálise , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/efeitos da radiação , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Águas Residuárias/microbiologia
7.
BMC Infect Dis ; 19(1): 386, 2019 May 06.
Artigo em Inglês | MEDLINE | ID: mdl-31060497

RESUMO

BACKGROUND: Ewingella americana (Ea) is a Gram-negative, lactose-fermenting, oxidase-negative and catalase-positive bacterium that was first described in 1983 as a new genus and species in the family Enterobacteriaceae. It is not known whether Ea is a true pathogen or simply an opportunistic infectious agent, as most of the cases have been described in patients at risk. CASE PRESENTATION: A 4-year-old girl described here was hospitalized due to a productive cough over the previous 3 weeks and a fever > 38 °C associated with tachypnea over the previous 2 days. Her familial and personal medical histories were negative for relevant diseases, including respiratory infections. At admission, she was febrile (axillary temperature 39.2 °C) and had dyspnea with retractions, grunting and nasal flaring. A chest examination revealed fine crackling rales in the left upper field associated with bilateral wheezing. A chest X-ray revealed segmental consolidation of the lingula of the left lung. Laboratory tests revealed leukocytosis (15.,800 white blood cells/mm3 with 50.3% neutrophils), a slight increase in serum C-reactive protein (11.9 mg/L) and normal procalcitonin values (< 0.12 ng/mL). A nasopharyngeal swab culture did not reveal viral or bacterial respiratory pathogens, including atypical bacteria. A blood culture revealed the presence of a Gram-negative, lactose-fermenting rod that was oxidase negative and catalase positive. The isolate was identified by means of the VITEK®2 identification system (bioMérieux, Firenze, Italy) as Ea. This identification was confirmed by sequencing the 16 s ribosomal deoxyribonucleic acid (rDNA). The pathogen was sensitive to aminoglycoside, fluoroquinolones, carbapenems, cefotaxime, and ceftazidime but was intermediate against sulfametoxazole/trimethoprim and resistant to amoxicillin-clavulanic acid, fosfomycin, and oxacillin. The child was immediately treated orally with amoxicillin-clavulanic acid and erythromycin. Based on the results of a blood culture and sensitivity tests, the amoxicillin-clavulanic acid medication was stopped after 3 days. Erythromycin was continued for a total of 10 days, and the child was discharged after 3 days in the hospital. Follow-up visit 1 month later did not reveal any respiratory problems. CONCLUSION: This case shows that Ea infections in healthy subjects are mild even in pediatric age, and the need for antibiotic therapy is debated. Cases occurring in subjects with underlying chronic disease can be significantly more complicated and require appropriate antibiotic therapy.


Assuntos
Antibacterianos/uso terapêutico , Pneumonia/tratamento farmacológico , Administração Oral , Aminoglicosídeos , Combinação Amoxicilina e Clavulanato de Potássio/uso terapêutico , Antibacterianos/farmacologia , Cefotaxima , Pré-Escolar , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Eritromicina/farmacologia , Eritromicina/uso terapêutico , Feminino , Fluoroquinolonas , Humanos , Itália , Pneumonia/microbiologia , Pneumonia/patologia , Tórax/diagnóstico por imagem
8.
Int J Food Microbiol ; 301: 19-26, 2019 Jul 16.
Artigo em Inglês | MEDLINE | ID: mdl-31071501

RESUMO

The increasing antimicrobial resistance (AMR) among pathogenic and opportunistic pathogenic microorganisms is one of the main global public health problems. The consumption of food contaminated with such bacteria (ARB), especially of raw products, might result in the direct acquisition of ARB and in a spread of resistant bacteria along the food chain. The aim of the study was to characterize the antimicrobial susceptibility of potentially extended spectrum ß-lactamase (ESBL) producing or AmpC resistant Enterobacteriaceae isolated from the surface of 147 muskmelons from wholesale and retail. A phenotypic analysis was carried out by using minimum inhibitory concentration (MIC) test strips for ESBL detection and MIC susceptibility plates against 14 antimicrobials. Furthermore, ESBL genes, sul-genes and plasmid-mediated AmpC resistance were analyzed by real-time PCR. Additionally, a further insight in the AmpC resistance of isolates of the Enterobacter cloacae complex (ECC) was obtained by analyzing the sequence of the ampC regulatory region (n = 15). A total of 73 potentially resistant Enterobacteriaceae were isolated from 56 muskmelons. Of these, 15 isolates of the ECC were suspicious for ESBL/AmpC resistance, and eleven thereof were positive for the AmpC family EBC. Phenotypic analysis showed diminished susceptibility against "critically" and "highly important" antimicrobials, according to the WHO classification. Furthermore, divergence in the ampC regulatory region was detected between the 15 isolates. These findings highlight the important role that raw produce might play in the transmission of antimicrobial resistances along the food chain.


Assuntos
Antibacterianos/farmacologia , Cucurbitaceae/microbiologia , Farmacorresistência Bacteriana/genética , Enterobacter cloacae/efeitos dos fármacos , Enterobacter cloacae/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Enterobacteriaceae/isolamento & purificação , Testes de Sensibilidade Microbiana , Plasmídeos/genética
9.
Braz J Infect Dis ; 23(2): 102-110, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-31028724

RESUMO

Enterobacteria-producing extended-spectrum ß-lactamases (ESBL) play an important role in healthcare infections, increasing hospitalization time, morbidity and mortality rates. Among several ESBLs that emerge from these pathogens, CTX-M-type enzymes had the most successful global spread in different epidemiological settings. Latin America presents high prevalence of CTX-M-2 in ESBL-producing enterobacterial infections with local emergence of the CTX-M-1 group. However, this high prevalence of the CTX-M-1 group has not yet been reported in Chile. The aim of this study was to identify ESBLs among enterobacteria isolated from clinical samples of critically ill patients from southern Chile. One-hundred thirty seven ESBL-producing bacteria were isolated from outpatients from all critical patient units from Hernán Henríquez Aravena Hospital. Phenotype characterization was performed by antibiogram, screening of ESBL, and determination of minimum inhibitory concentration (MIC). PCR was used for genetic confirmation of resistance. Molecular typing was performed by ERIC-PCR. ESBL-producing isolates were identified as Klebsiella pneumoniae (n=115), Escherichia coli (n=18), Proteus mirabilis (n=3), and Enterobacter cloacae (n=1), presenting multidrug resistance profiles. PCR amplification showed that the strains were positive for blaSHV (n=111/81%), blaCTX-M-1 (n=116/84.7%), blaTEM (n=100/73%), blaCTX-M-2 (n=28/20.4%), blaCTX-M-9 (0.7%), blaPER-1 (0.7%), and blaGES-10 (0.7%). The multiple production of ESBL was observed in 93% of isolates, suggesting high genetic mobility independent of the clonal relationship. The high frequency of the CTX-M-1 group and a high rate of ESBL co-production are changing the epidemiology of the ESBL profile in Chilean intensive care units. This epidemiology is a constant and increasing challenge, not only in Chile, but worldwide.


Assuntos
Infecções por Enterobacteriaceae/enzimologia , Infecções por Enterobacteriaceae/epidemiologia , Enterobacteriaceae/enzimologia , Unidades de Terapia Intensiva/estatística & dados numéricos , beta-Lactamases/genética , Antibacterianos/farmacologia , Chile/epidemiologia , DNA Bacteriano , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/microbiologia , Técnicas de Genotipagem , Humanos , Testes de Sensibilidade Microbiana , Reação em Cadeia da Polimerase , Prevalência , Valores de Referência , Fatores de Risco , beta-Lactamases/isolamento & purificação
10.
Benef Microbes ; 10(4): 413-424, 2019 Apr 19.
Artigo em Inglês | MEDLINE | ID: mdl-30957532

RESUMO

Probiotics should bring 'balance' to the intestinal microbiota by stimulating beneficial bacteria, whilst mitigating adverse ones. Balance can also be interpreted as high alpha-diversity. Contrary, Escherichia coli is often regarded as an adverse component of the resident intestinal microbiota. The aim of the present study was to implement a mouse model for in vivo screening of Lactobacillus-strains for ability to increase gut-microbiota diversity and to mitigate E. coli. Mice were divided into six groups, two dietary control-groups and four groups administered strains of Lactobacillus fermentum and/or Lactobacillus plantarum. All animals were pre-treated with antibiotics, and E. coli in order to equalise the microbiota from the start. After 7 weeks of Lactobacillus administration, the animals were sacrificed: DNA was extracted from caecum tissue, and the microbiota composition was analysed with terminal restriction fragment length polymorphism (T-RFLP) and 16S rRNA gene sequencing. The diversity of the caecal microbiota decreased when the dietary carbohydrate source was limited to corn starch. Conversely, the diversity was restored by Lactobacillus-supplements. The tested combinations of two Lactobacillus strains exerted different influences, not only on the taxonomic level, but also on the inferred microbiome functions. The mixture of L. fermentum GOS47 and L. fermentum GOS1 showed potential for anti-inflammatory activity and short chain fatty acid production. On the other hand, co-administration of L. fermentum GOS57 and L. plantarum GOS42 significantly decreased the viable count of Enterobacteriaceae. These results warrant further investigation of the tested strains as candidates for probiotics. Furthermore, the findings demonstrated that the current experimental animal model is suitable for in vivo studies of the effect of bacterial supplements on the gut-microbiota.


Assuntos
Microbioma Gastrointestinal/fisiologia , Lactobacillus fermentum/fisiologia , Lactobacillus plantarum/fisiologia , Probióticos/administração & dosagem , Animais , Anti-Inflamatórios/administração & dosagem , Anti-Inflamatórios/farmacologia , Biodiversidade , Ceco/química , Ceco/microbiologia , DNA Bacteriano/genética , Dieta , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Ácidos Graxos Voláteis/metabolismo , Microbioma Gastrointestinal/efeitos dos fármacos , Microbioma Gastrointestinal/genética , Lactobacillus/efeitos dos fármacos , Lactobacillus/isolamento & purificação , Lactobacillus fermentum/metabolismo , Lactobacillus plantarum/metabolismo , Masculino , Camundongos Endogâmicos C57BL , Viabilidade Microbiana , Polimorfismo de Fragmento de Restrição/genética , Probióticos/farmacologia , RNA Ribossômico 16S/genética , Especificidade da Espécie
11.
J Med Microbiol ; 68(5): 711-719, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30994430

RESUMO

PURPOSE: Antimicrobial resistance (AMR) is of increasing global concern, threatening to undermine recent progress in reducing child and neonatal mortality. Repurposing older antimicrobials is a prominent strategy to combat multidrug-resistant sepsis. A potential agent is fosfomycin, however, there is scarce data regarding its in vitro activity and pharmacokinetics in the paediatric population. METHODOLOGY: We analysed a contemporary, systematically collected archive of community-acquired (CA) and hospital-acquired (HA) paediatric Gram-negative bacteraemia isolates for their susceptibility to fosfomcyin. MICs were determined using agar serial dilution methods and validated by disk diffusion testing where breakpoints are available. Disk diffusion antimicrobial susceptibility testing was also conducted for current empirical therapies (ampicillin, gentamicin, ceftriaxone) and amikacin (proposed in the literature as a new combination empirical therapeutic option). RESULTS: Fosfomycin was highly active against invasive Gram-negative isolates, including 90  % (202/224) of Enterobacteriaceae and 96  % (22/23) of Pseudomonas spp. Fosfomycin showed high sensitivity against both CA isolates (94 %, 142/151) and HA isolates (81 %, 78/96; P =0.0015). CA isolates were significantly more likely to be susceptible to fosfomycin than the current first-line empirical therapy (96  % vs 59  %, P <0.0001). Extended spectrum ß-lactamases (ESBL) production was detected in 34  % (85/247) of isolates with no significant difference in fosfomycin susceptibility between ESBL-positive or -negative isolates [73/85 (86  %) vs 147/162 (91  %) respectively, P =0.245]. All isolates were susceptible to a fosfomycin-amikacin combination. CONCLUSION: Gram-negative paediatric bacteraemia isolates are highly susceptible to fosfomycin, which could be combined with aminoglycosides as a new, carbapenem-sparing regimen to achieve excellent coverage to treat antimicrobial-resistant neonatal and paediatric sepsis.


Assuntos
Antibacterianos/farmacologia , Fosfomicina/farmacologia , Bactérias Gram-Negativas/efeitos dos fármacos , Bacteriemia/tratamento farmacológico , Pré-Escolar , Infecções Comunitárias Adquiridas/microbiologia , Infecção Hospitalar/tratamento farmacológico , Enterobacteriaceae/efeitos dos fármacos , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Escherichia coli/tratamento farmacológico , Feminino , Humanos , Lactente , Recém-Nascido , Klebsiella pneumoniae/efeitos dos fármacos , Masculino , Testes de Sensibilidade Microbiana , Pseudomonas/efeitos dos fármacos , Sepse/tratamento farmacológico , Sepse/microbiologia
12.
Acta Vet Scand ; 61(1): 21, 2019 Apr 25.
Artigo em Inglês | MEDLINE | ID: mdl-31023344

RESUMO

The use of pre- and post-milking teat disinfectants can reduce teat bacterial load and aid in the collection of high-quality milk. The objective of this study was to compare the reduction in bacteria populations on teat skin after the application of different commercial teat disinfectant products. Ten teat disinfectant products were applied to the teats of 10 Holstein-Friesian cows. One cow received one teat disinfectant product at each sampling point before cluster application for milking. A composite swab sample was taken of the 4 teats of each cow before and after teat disinfectant application. Swab samples were placed on three different selective agars to enumerate bacterial counts of staphylococcal, streptococcal and coliforms isolates on teat skin. Staphylococcal isolates were the most prominent bacterial group recovered on teat swabs (49%), followed by streptococcal (36%) and coliform (15%) isolates before the application of disinfectant. The average bacterial reductions on teat skin were shown to be 76%, 73% and 60% for staphylococcal, streptococcal and coliform isolates, respectively. All of the teat disinfectant products tested reduced teat bacterial load for all three bacterial groups. Product 4 containing 0.6% w/w diamine was the most effective against bacterial populations of staphylococcal and streptococcal isolates on teat skin with a reduction of 90% and 94%, respectively. Whereas product 10, which contained 0.5% w/w iodine, resulted in the highest reduction in coliforms on teat skin with a reduction of 91%. Results from this study suggest that specific bacterial population loads on teats can be reduced using different teat disinfectant formulations.


Assuntos
Bactérias/efeitos dos fármacos , Desinfetantes/farmacologia , Glândulas Mamárias Animais/microbiologia , Mastite Bovina/prevenção & controle , Pele/microbiologia , Animais , Bactérias/classificação , Bovinos , Desinfetantes/química , Enterobacteriaceae/efeitos dos fármacos , Feminino , Mastite Bovina/microbiologia , Staphylococcus/efeitos dos fármacos , Streptococcus/efeitos dos fármacos
13.
Emerg Microbes Infect ; 8(1): 564-574, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30945610

RESUMO

Tigecycline is regarded as a last-resort treatment for carbapenem-resistant Enterobacteriaceae (CRE), however, the emergence of tigecycline heteroresistance has posted the therapeutic challenge to combat this "nightmare bacteria". The primary purpose of this study was to demonstrate the existence of tigecycline heteroresistance in carbapenem-resistant E. cloacae (TH-CRECL) and further to explore the epidemiological characteristics and underlying molecular mechanisms. Our study identified a relative low prevalence of carbapenem-resistant E. cloacae (CRECL) isolates, about 20.0% (28/140), as heteroresistance to tigecycline. Molecular genetic relatedness of these heteroresistant isolates were characterized epidemiologically sporadic. In addition, mechanistic analysis revealed that Phe-Arg-ß-naphthylamide (PAßN) significantly reversed tigecycline MIC levels of resistant colonies in heteroresistant strains, as primarily related to the marked overproduction of efflux pump genes acrAB and oqxAB, as well as overexpression of transcriptional regulators (soxS and ramA). Moreover, logistic regression analysis showed that previous fluoroquinolone therapy was identified as the only potential independent risk factor for the acquisition of TH-CRECL. Most importantly, our data indicated that patients with TH-CRECL infection might lead to a remarkably prolonged hospital stay and deterioration in functional status. These findings emphasized the necessity of timely detection and intervention of patients infected with TH-CRECL.


Assuntos
Antibacterianos/farmacologia , Farmacorresistência Bacteriana , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Idoso , Proteínas de Bactérias/genética , Proteínas de Bactérias/metabolismo , Carbapenêmicos/farmacologia , Proteínas de Transporte/genética , Proteínas de Transporte/metabolismo , China , Enterobacteriaceae/genética , Enterobacteriaceae/metabolismo , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Estudos Retrospectivos , Tigeciclina/farmacologia
14.
Mediators Inflamm ; 2019: 2020858, 2019.
Artigo em Inglês | MEDLINE | ID: mdl-30837795

RESUMO

Burn injury is a growing medical problem associated with public health, and few effective agents are available for treatment of this disease. In the present study, a burn injury rat model was developed and the accelerated effect of Aloe vera fermentation on burn injury healing was evaluated. Our results indicated that Aloe vera fermentation could markedly reduce the DPPH (56.12%), O2·- (93.5%), ·OH (76.12%), Fe2+ chelation (82%), and oxygen-reduction activity (0.28 µg/ml) and significantly inhibited the growth of pathogens S. typhimurium ATCC 13311 (inhibition zone diameter: 14 mm), S. enteritidis ATCC13076 (IZD: 13 mm), S. flexneri ATCC 12022 (IZD: 18 mm), E. coli 44102 (IZD: 10 mm), L. monocytogenes ATCC 19111 (IZD: 18 mm), S. dysenteriae 301 (IZD: 20 mm), S. aureus COWAN1 (IZD: 19 mm), and P. acnes ATCC 11827 (IZD: 25 mm) in vitro. The in vivo results indicated that Aloe vera fermentation produced more eosinophils and fibroblasts and less vessel proliferation compared with the model group on the 14th day, which had greatly accelerated burn injury healing via shedding of the scab and promoting hair growth. ELISA results indicated that Aloe vera fermentation had significantly reduced the production of proinflammatory factors TNF-α and IL-1ß (p < 0.05) and greatly enhanced the yield of anti-inflammatory factor IL-4 in animal serum (p < 0.05). In addition, the high-throughput sequencing results indicated that Aloe vera fermentation obviously increased the percentage of Firmicutes (65.86% vs. 49.76%), while reducing the number of Bacteroidetes (27.60% vs. 45.15%) compared with the M group at the phylum level. At the genus level, Aloe vera fermentation increased the probiotic bacteria Lactobacillus (3.13% vs. 2.09%) and reduced the pathogens Prevotella (10.60% vs.18.24%) and Blautia (2.91% vs. 16.41%) compared with the M group. Therefore, we concluded that the use of Aloe vera fermentation significantly accelerates burn injury healing via reduction of the severity of inflammation and through modification of gut microbiota.


Assuntos
Aloe/metabolismo , Queimaduras/tratamento farmacológico , Fermentação/fisiologia , Extratos Vegetais/uso terapêutico , Animais , Antibacterianos , Antioxidantes/farmacologia , Antioxidantes/uso terapêutico , Enterobacteriaceae/efeitos dos fármacos , Enterococcus/efeitos dos fármacos , Ensaio de Imunoadsorção Enzimática , Feminino , Extratos Vegetais/farmacologia , Ratos , Software
15.
Eur J Clin Microbiol Infect Dis ; 38(5): 937-944, 2019 May.
Artigo em Inglês | MEDLINE | ID: mdl-30868326

RESUMO

Extended-spectrum ß-lactamase-producing Enterobacteriales (ESBL-PE) are often associated with inappropriate empirical therapy (IAT). The aim of this study was to investigate whether IAT of acute pyelonephritis (APN) caused by ESBL-PE is related to adverse outcomes. A retrospective cohort study was performed at a tertiary-care hospital from 2014 through 2016. Patients who had APN caused by ESBL-PE and were definitely treated with appropriate antibiotics for at least 7 days were enrolled. IAT was defined as when inappropriate empirical antibiotics were given 48 h or longer after initial diagnosis of APN. Primary endpoint was treatment failure defined as clinical and/or microbiologic failure. Secondary endpoints were length of hospital stay and recurrence of APN. Propensity score matching was used to adjust heterogeneity of each group. Among 175 eligible cases, 59 patients received IAT and 116 patients received appropriate empirical antimicrobial therapy (AT). Treatment failure was observed in five (8.4%) patients and nine (7.8%) patients in each group, respectively. After matching, the treatment failure rate was similar between both groups (adjusted odd ratio [aOR] 1.05; 95% confidence index [CI] 0.26-4.15). The length of hospital stay (median 11 days in the IAT group versus 11 days in the AT group; P = 0.717) and absence of recurrence within 2 months (90.3% in IAT and 86.7% in AT; P = 0.642) were also similar. IAT did not adversely affect the clinical outcome. In this regard, clinicians should be more cautious about indiscriminate prescription of broad-spectrum antibiotics such as carbapenem empirically for treatment of APN possibly caused by ESBL-PE.


Assuntos
Antibacterianos/uso terapêutico , Infecções por Enterobacteriaceae/tratamento farmacológico , Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/enzimologia , Pielonefrite/tratamento farmacológico , Pielonefrite/microbiologia , beta-Lactamases/biossíntese , Doença Aguda , Idoso , Antibacterianos/efeitos adversos , Antibacterianos/farmacologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/isolamento & purificação , Infecções por Enterobacteriaceae/diagnóstico , Feminino , Humanos , Tempo de Internação , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Pielonefrite/diagnóstico , República da Coreia , Estudos Retrospectivos , Centros de Atenção Terciária , Falha de Tratamento , Resultado do Tratamento
16.
Braz J Microbiol ; 50(2): 425-428, 2019 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-30859495

RESUMO

Two hundred isolates of Enterobacterales were tested by Rapid Polymyxins NP for the detection of polymyxin resistance and compared to the reference test broth microdilution (BMD). The sensitivity and specificity of the NP test were 98% and the results are faster than the BMD, decreasing from approximately 24 to 2 h.


Assuntos
Antibacterianos/farmacologia , Colistina/farmacologia , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Polimixina B/farmacologia , Enterobacteriaceae/isolamento & purificação , Etanolaminofosfotransferase/genética , Humanos , Testes de Sensibilidade Microbiana
17.
Food Chem ; 287: 280-286, 2019 Jul 30.
Artigo em Inglês | MEDLINE | ID: mdl-30857701

RESUMO

The effect of winter savory (Satureja montana L.) essential oil (SEO) and supercritical extracts (SE1; SE2) at concentrations of 0.075 and 0.150 µL/g on pH, lipid oxidation (TBARS), microbial growth and sensory quality of fresh pork sausages during storage were investigated. SEO, SE1 and SE2 improved oxidative and microbial stability of fresh pork sausages. The addition of SEO and SE1 at concentration of 0.150 µL/g affected the reduction of total Enterobacteriaeceae count to under 3 log cfu/g. Sausages produced with SE1 and SE2 had a higher scores for odor, flavor and overall acceptance compared to sausages treated with SEO and control sample. Therefore, the results of this paper revealed significant antioxidative and antimicrobial activity of SE1 and SE2, and consequently its high potential of utilization in processing of fresh pork sausages.


Assuntos
Aditivos Alimentares/química , Óleos Voláteis/química , Extratos Vegetais/química , Carne Vermelha , Satureja/química , Animais , Antioxidantes , Enterobacteriaceae/efeitos dos fármacos , Aditivos Alimentares/farmacologia , Qualidade dos Alimentos , Humanos , Concentração de Íons de Hidrogênio , Produtos da Carne/análise , Produtos da Carne/microbiologia , Odorantes/análise , Óleos Voláteis/farmacologia , Oxirredução , Extratos Vegetais/farmacologia , Carne Vermelha/análise , Carne Vermelha/microbiologia , Suínos , Paladar , Substâncias Reativas com Ácido Tiobarbitúrico/metabolismo
18.
BMC Infect Dis ; 19(1): 205, 2019 Feb 28.
Artigo em Inglês | MEDLINE | ID: mdl-30819135

RESUMO

BACKGROUND: Extended-spectrum ß-lactamase-producing Enterobacteriaceae (ESBL-PE) represent a major problem in the management of nosocomial infections. However, ESBL-PE are not systematically monitored in African countries. The aim of this study was to determine ESBL-PE prevalence in patients from three hospitals in N'Djamena, the capital city of Chad, and to characterize the genetic origin of the observed resistance. METHODS: From January to March 2017, 313 non-duplicate isolates were recovered from various clinical specimens obtained from 1713 patients in the three main hospitals of N'Djamena. Bacterial species were identified by matrix-assisted laser desorption ionization-time of flight mass spectrometry. Susceptibility to 28 antibiotics was tested using the disk diffusion method on Müller-Hinton agar, and ESBL production was confirmed with the double-disc synergy test. The most prevalent ESBL genes associated with the observed resistance were detected using multiplex PCR followed by double-stranded DNA sequencing. RESULTS: Among the 313 isolates, 197 belonged to the Enterobacteriaceae family. The overall ESBL-PE prevalence was 47.72% (n = 94/197), with a higher rate among inpatients compared with outpatients (54.13% vs. 34.37%). ESBL-PE prevalence was highest in older patients (≥60 years of age). E. coli was the most common ESBL-producer organism (63.8%), followed by K. pneumoniae (21.2%). ESBL-PE were mainly found in urine samples (75%). The CTX-M-1 group was dominant (96.7% of the 94 ESBL-PE isolates, CTX-M-15 enzyme), followed by the CTX-M-9 group (4.1%). 86% of resistant isolates harbored more than one ESBL-encoding gene. ESBL production was also associated with the highest levels of resistance to non-ß-lactam drugs. CONCLUSIONS: The prevalence of ESBL-PE harboring resistant genes encoding ESBLs of the CTX-M-1 group was high (48%) among clinical isolates of three main hospitals in Chad, suggesting an alarming spread of ESBL-PE among patients.


Assuntos
Infecções por Enterobacteriaceae/microbiologia , Enterobacteriaceae/genética , beta-Lactamases/genética , Adolescente , Adulto , Idoso , Idoso de 80 Anos ou mais , Antibacterianos/farmacologia , Chade/epidemiologia , Criança , Pré-Escolar , Infecção Hospitalar/microbiologia , Farmacorresistência Bacteriana/efeitos dos fármacos , Farmacorresistência Bacteriana/genética , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/patogenicidade , Infecções por Enterobacteriaceae/epidemiologia , Feminino , Hospitais , Humanos , Masculino , Testes de Sensibilidade Microbiana , Pessoa de Meia-Idade , Prevalência
19.
BMC Infect Dis ; 19(1): 163, 2019 Feb 14.
Artigo em Inglês | MEDLINE | ID: mdl-30764770

RESUMO

BACKGROUND: Bacterial resistance to first line antibiotics used to treat community-onset urinary tract infections (UTIs) continues to emerge. We sought to determine the association between extended-spectrum cephalosporin resistance (ESC-R) and recurrence among Enterobacteriaceae (EB) UTIs. METHODS: A retrospective cohort study was performed. All patients presenting to the Emergency Departments (EDs) or outpatient practices in a large health system with EB UTIs between 2010 and 2013 were included. Exposed patients had ESC-R EB UTIs. Unexposed patients had ESC-susceptible EB UTIs and were matched to exposed patients 1:1 on study year. Multivariable Cox proportional hazards regression analyses were performed to evaluate the association between ESC-R EB UTI and time to recurrent UTI within 12 months. RESULTS: A total of 302 patients with an index community-onset EB UTI were included, with 151 exposed and 151 unexposed. Overall, 163 (54%) patients experienced a recurrent UTI with a median time to recurrence of 69 days (interquartile range 25-183). On multivariable analyses, ESC-resistance was associated with an increased hazard of recurrent UTI (hazard ratio [HR] 1.39, 95% confidence interval [CI] 1.01-1.91, P = 0.04). Other variables that were independently associated with recurrence included a history of UTI prior to the index UTI and presence of a urinary catheter at the time of the index UTI. Secondarily, we found that when the treatment for the index UTI was adjusted for, there was no longer a significant association between ESC-R status and time to recurrent UTI (aHR 1.26, 95% CI 0.91-1.76, P = 0.17). CONCLUSIONS: Community-onset UTI due to EB demonstrating ESC-resistance is associated with a significantly increased hazard of recurrent UTI within 12 months compared to ESC-susceptible EB, even after adjusting for baseline factors that predispose patients to UTI recurrence. This association appears to be driven primarily by delayed or inappropriate treatment for the index ESC-R EB UTI.


Assuntos
Resistência às Cefalosporinas , Cefalosporinas/uso terapêutico , Infecções Comunitárias Adquiridas , Infecções por Enterobacteriaceae/epidemiologia , Infecções por Enterobacteriaceae/microbiologia , Infecções Urinárias/epidemiologia , Infecções Urinárias/microbiologia , Adulto , Idoso , Antibacterianos/uso terapêutico , Resistência às Cefalosporinas/efeitos dos fármacos , Resistência às Cefalosporinas/genética , Estudos de Coortes , Infecções Comunitárias Adquiridas/tratamento farmacológico , Infecções Comunitárias Adquiridas/epidemiologia , Infecções Comunitárias Adquiridas/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Enterobacteriaceae/genética , Infecções por Enterobacteriaceae/tratamento farmacológico , Feminino , Humanos , Masculino , Pessoa de Meia-Idade , Recidiva , Estudos Retrospectivos , Infecções Urinárias/tratamento farmacológico , beta-Lactamases/genética
20.
Diagn Microbiol Infect Dis ; 94(2): 116-121, 2019 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-30711413

RESUMO

OBJECTIVE: Optimizing therapy for bacteremia is currently limited by the 1-2-day turnaround time required for antimicrobial susceptibility testing (AST). Here, we assess a rapid AST method with VITEK®2 (bioMérieux, France) directly from positive blood cultures. METHODS: Patient-derived positive blood cultures with Gram-negative rods identified as Enterobacteriaceae and Pseudomonas aeruginosa were prospectively tested, and other blood culture bottles were spiked with carbapenem-resistant Enterobacteriaceae (CRE). Positive cultures were subjected to red blood cell lysis and centrifugation, and setup on VITEK®2. RESULTS: A total of 109 patient blood cultures and 52 spiked blood cultures were tested. Overall, essential agreement was 97.7% [95% confidence interval (CI) 96.4-99.0], and categorical agreement was 96.8% (95% CI 95.0-98.6). Mean turnaround time from setup to susceptibility results for Enterobacteriaceae in the clinical cultures was 9.0 (±1.3) h. CONCLUSIONS: Direct susceptibility testing of blood cultures by VITEK®2 for Enterobacteriaceae is an accurate, practical, and inexpensive diagnostic strategy for rapid automated AST.


Assuntos
Antibacterianos/farmacologia , Bacteriemia/microbiologia , Sangue/microbiologia , Enterobacteriaceae/efeitos dos fármacos , Infecções por Bactérias Gram-Negativas/microbiologia , Testes de Sensibilidade Microbiana/métodos , Pseudomonas aeruginosa/efeitos dos fármacos , Infecções por Enterobacteriaceae/microbiologia , França , Humanos , Estudos Prospectivos , Infecções por Pseudomonas/microbiologia , Fatores de Tempo
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