scholarly journals Results from a Prospective In Vitro Study on the Mecillinam (Amdinocillin) Susceptibility of Enterobacterales

2019 ◽  
Vol 63 (4) ◽  
Author(s):  
Frieder Fuchs ◽  
Axel Hamprecht

ABSTRACT The activity of mecillinam (amdinocillin) was assessed in Enterobacterales (n = 420) isolated from urine samples between 2016 and 2017. Mecillinam susceptibilities were 97.4% in Escherichia coli isolates (294/302), 89.7% in Klebsiella spp. isolates (52/58), and 93.3% in Proteus mirabilis isolates (28/30). Among extended-spectrum β-lactamase (ESBL) producers, 95.2% (99/104) were mecillinam susceptible, including two OXA-48-producing Klebsiella pneumoniae isolates. In Enterobacter spp. and Citrobacter spp., MICs were low (MIC50 = 0.5 mg/liter). In conclusion, the activity of mecillinam was high in Enterobacterales, even among multidrug-resistant isolates.

2021 ◽  
Vol 13 (5) ◽  
pp. 590
Author(s):  
Mohammed Abidullah ◽  
Pradnya Jadhav ◽  
SSri Sujan ◽  
AyyapaGandhi Shrimanikandan ◽  
ChukkaRakesh Reddy ◽  
...  

2016 ◽  
Vol 11 (31) ◽  
pp. 113-122
Author(s):  
Carla Franco Porto Belmont Souza ◽  
Luiz Eduardo Souza da Silva Irineu ◽  
Renan Silva De Souza ◽  
Renato da Silva Teixeira ◽  
Ivina Sanches Pereira ◽  
...  

A resistência microbiana tem se mostrado um problema de proporções mundiais, causando estado de morbidade e mortalidade em diversos pacientes. Em vista disso, tem crescido a busca por métodos alternativos naturais de profilaxia. A investigação clínica sugere que o Extrato de Cranberry está entre as melhores propostas de prevenção natural. O Cranberry (Vaccinium macrocarpon) é um fruto que tem crescido comercialmente pelo sabor e propriedades benéficas à saúde. Dentre as formas comercializadas estão: o suco, o chá e as cápsulas contendo o extrato seco. A ação desta planta está relacionada ao tratamento de doenças do trato urinário, por possuir substâncias que inibem a adesão bacteriana ao epitélio do trato urinário, dificultando sua proliferação e reprodução. Dentre todas as infecções relacionadas à assistência a saúde, a Infecção do Trato Urinário é a mais frequentemente associada a procedimentos invasivos. Se não for tratada, pode resultar em complicações como pielonefrite aguda, bacteremia e pionefrose. Portanto, cranberry pode ser uma nova alternativa para o combate das infecções uroepiteliais, por ser um produto natural de preço acessível, e com formas de comercialização diversificada, ao contrário dos antimicrobianos convencionais, que por sua vez são caros e podem acabar causando resistência nos micro-organismos. Este trabalho teve como objetivo avaliar in vitro a atividade antimicrobiana do extrato de Cranberry, adquirido em farmácia de manipulação, sobre 8 micro-organismos isolados de infecções urinárias. As cepas utilizadas, adquiridas da coleção da FIOCRUZ, foram: Escherichia coli, Pseudomonas aeruginosa, Klebsiella pneumoniae, Proteus mirabilis, Serratia marscecens, Staphylococcus aureus, Enterococcus faecalis e Enterococcus faecium. No estudo, foram utilizados o caldo Mueller Hinton (MH), Extrato de Cranberry e as bactérias patogênicas. O ensaio foi realizado em triplicata, com o uso de um controle de crescimento dos micro-organismos e o experimento para avaliação do crescimento bacteriano na presença do extrato. A turbidez foi medida com o auxílio de um espectrofotômetro, no comprimento de onda de 600 nm, antes e após 24 horas de incubação à 37 ºC. O procedimento forneceu a Densidade Ótica, do qual possibilitou a identificação da inibição microbiana. Para análise estatística foi utilizado o Teste t de Student. O Extrato de Cranberry apresentou atividade antimicrobiana sobre as bactérias Staphylococcus aureus, Klebsiella pneumoniae, Escherichia coli, Serratia marscecens e Enterococcus faecalis (p < 0,05), confirmando seu efeito benéfico em infecções urinárias. No entanto, não teve efeito inibitório significativo sobre Pseudomonas aeruginosa, Proteus mirabilis e Enterococcus faecium (p > 0,05).


2019 ◽  
Vol 63 (6) ◽  
Author(s):  
Katharina Schaufler ◽  
Torsten Semmler ◽  
Lothar H. Wieler ◽  
Darren J. Trott ◽  
Johann Pitout ◽  
...  

ABSTRACT The pathogenic extended-spectrum-beta-lactamase (ESBL)-producing Escherichia coli lineage ST648 is increasingly reported from multiple origins. Our study of a large and global ST648 collection from various hosts (87 whole-genome sequences) combining core and accessory genomics with functional analyses and in vivo experiments suggests that ST648 is a nascent and generalist lineage, lacking clear phylogeographic and host association signals. By including large numbers of ST131 (n = 107) and ST10 (n = 96) strains for comparative genomics and phenotypic analysis, we demonstrate that the combination of multidrug resistance and high-level virulence are the hallmarks of ST648, similar to international high-risk clonal lineage ST131. Specifically, our in silico, in vitro, and in vivo results demonstrate that ST648 is well equipped with biofilm-associated features, while ST131 shows sophisticated signatures indicative of adaption to urinary tract infection, potentially conveying individual ecological niche adaptation. In addition, we used a recently developed NFDS (negative frequency-dependent selection) population model suggesting that ST648 will increase significantly in frequency as a cause of bacteremia within the next few years. Also, ESBL plasmids impacting biofilm formation aided in shaping and maintaining ST648 strains to successfully emerge worldwide across different ecologies. Our study contributes to understanding what factors drive the evolution and spread of emerging international high-risk clonal lineages.


2000 ◽  
Vol 12 (3) ◽  
pp. 218-223 ◽  
Author(s):  
R. van den Hoven ◽  
J. A. Wagenaar ◽  
R. D. Walker

The in vitro activity of difloxacin against canine bacterial isolates from clinical cases was studied in the United States and The Netherlands. Minimal inhibitory concentrations (MIC), the postantibiotic effect, the effect of pH on antimicrobial activity, and the bacterial killing rate tests were determined according to standard techniques. The MICs of American and Dutch isolates agreed in general. The MICs of the American gram-negative isolates ranged from 0.06 to 2.0 μg/ml, and the MICs of the Dutch gram-negative isolates ranged from 0.016 to 8.0 μg/ml. A few European strains of Proteus mirabilis and Klebsiella pneumoniae had relatively high MICs. Bordetella bronchiseptica also was less susceptible to difloxacin. The MICs of the American gram-positive cocci ranged from 0.125 to 4.0 μg/ml, and the MICs of Dutch isolates ranged from 0.125 to 2.0 μg/ml. Difloxacin induced a concentration-dependent postantibiotic effect that lasted 0.2–3 hours in cultures with Escherichia coli, Staphylococcus intermedius, Streptococcus canis, Proteus spp., and Klebsiella pneumoniae. There was no postantibiotic effect observed against canine Pseudomonas aeruginosa. Decreasing the pH of the medium increased the MIC of Proteus mirabilis for difloxacin. The MICs of Escherichia coli and Klebsiella pneumoniae were lowest at neutral pH and were slightly increased in acid or alkaline media. At a neutral pH, most tested bacterial species were killed at a difloxacin concentration of 4 times the MIC. Similar results were obtained when these same bacteria were tested against enrofloxacin. A Klebsiella pneumoniae strain in an acidic environment was readily killed at difloxacin or enrofloxacin MIC, but at neutral pH the drug concentration had to be raised to 4 times the MIC for a bactericidal effect. After 24 hours of incubation at pH 7.1, difloxacin and enrofloxacin had similar bactericidal activity for all bacteria tested except Staphylococcus intermedius. Against S. intermedius, difloxacin was more bactericidal than enrofloxacin.


2018 ◽  
Vol 62 (8) ◽  
Author(s):  
M. Thwaites ◽  
D. Hall ◽  
D. Shinabarger ◽  
A. W. Serio ◽  
K. M. Krause ◽  
...  

ABSTRACT The next-generation aminoglycoside plazomicin, in development for infections due to multidrug-resistant (MDR) Enterobacteriaceae, was evaluated alongside comparators for bactericidal activity in minimum bactericidal concentration (MBC) and time-kill (TK) assays against MDR Enterobacteriaceae isolates with characterized aminoglycoside and β-lactam resistance mechanisms. Overall, plazomicin and colistin were the most potent, with plazomicin demonstrating an MBC50/90 of 0.5/4 μg/ml and sustained 3-log10 kill against MDR Escherichia coli, Klebsiella pneumoniae, and Enterobacter spp.


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