Antimicrobial Resistance in Enteric Gram-Negative Organisms

2016 ◽  
Author(s):  
Allison Mah ◽  
Inna Sekirov ◽  
Theodore S Steiner
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Clinical Manifestations ◽  
Treatment Strategies ◽  
Resistance Mechanisms ◽  
Current Treatment ◽  
Health Care Use ◽  
Gram Negative ◽  
Gram Negative Organisms ◽  
The Many

Antimicrobial resistance is a phenomenon that predates the introduction of antibiotics into clinical practice and has become an exponentially growing problem worldwide, leading to increased mortality and increased costs of health care use. Among the many organisms with ever-worsening resistance profiles, Escherichia coli and other Enterobacteriaceae species are significant pathogens, both in terms of numbers and the severity of the infections they cause. The purpose of this review is to examine the emerging concern of antimicrobial resistance and the approach to treatment in the setting of infection with resistant organisms. We will focus on the resistance mechanisms of Enterobacteriaceae to select antimicrobial classes, briefly discuss the epidemiology of resistance, and discuss current treatment strategies. The specific epidemiology, clinical manifestations, and treatment of individual members of the Enterobacteriaceae are discussed in the review “Infections Due to Escherichia coli and Other Enteric Gram-Negative Bacilli,” found elsewhere in this publication. Figures illustrate the mechanisms of antimicrobial resitance in Enterobacteriaceae. Tables list the Ambler classification of ESBL/AmpC and carbapenemase enzymes, and antibiotics with activity against carbapenem-resistant enterobacteriaceae. This review contains 4 highly rendered figures, 2 tables, and 27 references.

Infections due to Escherichia coli and Other Enteric Gram-Negative Bacilli

2016 ◽  
Author(s):  
Allison Mah ◽  
Inna Sekirov ◽  
Theodore S Steiner
Keyword(s):  
Escherichia Coli ◽  
Gastrointestinal Tract ◽  
Antimicrobial Resistance ◽  
Clinical Manifestations ◽  
Gram Negative ◽  
The Family ◽  
Enteric Infections ◽  
Gram Negative Organisms ◽  
Tract Infections

This review describes infections caused by Escherichia coli and related members of the family Enterobacteriaceae, excluding other genera that principally cause enteric infections. Infections caused by Salmonella, Shigella, and Yersinia are described in the review “Gastrointestinal Tract Infections," found elsewhere in this publication. The purpose of this review is to examine the specific epidemiology, clinical manifestations, and treatment of individual members of the Enterobacteriaceae. The emerging concern of antimicrobial resistance amongst enteric gram-negative organisms and the approach to treatment in the setting of infection with these resistant organisms are discussed in the review “Antimicrobial Resistance in Enteric Gram-Negative Organisms,” found elsewhere in this publication. Figures illustrate the mechanisms of antimicrobial resistance in Enterobacteriaceae. A table lists the clinical, epidemiologic, pathogenetic, and therapeutic aspects of infection with various pathotypes of Escherichia coli. This review contains 6 highly rendered figures, 1 table, and 79 references.

Intrinsic, adaptive and acquired antimicrobial resistance in Gram-negative bacteria

2017 ◽  
Vol 61 (1) ◽  
pp. 49-59 ◽  
Author(s):  
Mohsen Arzanlou ◽  
Wern Chern Chai ◽  
Henrietta Venter
Keyword(s):  
Antimicrobial Resistance ◽  
Molecular Mechanisms ◽  
Resistance Mechanisms ◽  
Stress Conditions ◽  
Gram Negative Bacteria ◽  
Mechanisms Of Resistance ◽  
Intrinsic Resistance ◽  
Antimicrobial Drugs ◽  
Gram Negative ◽  
Gram Negative Organisms

Gram-negative bacteria are responsible for a large proportion of antimicrobial-resistant infections in humans and animals. Among this class of bacteria are also some of the most successful environmental organisms. Part of this success is their adaptability to a variety of different niches, their intrinsic resistance to antimicrobial drugs and their ability to rapidly acquire resistance mechanisms. These mechanisms of resistance are not exclusive and the interplay of several mechanisms causes high levels of resistance. In this review, we explore the molecular mechanisms underlying resistance in Gram-negative organisms and how these different mechanisms enable them to survive many different stress conditions.

scholarly journals In VivoComparison of CXA-101 (FR264205) with and without Tazobactam versus Piperacillin-Tazobactam Using Human Simulated Exposures against Phenotypically Diverse Gram-Negative Organisms

2011 ◽  
Vol 56 (1) ◽  
pp. 544-549 ◽  
Author(s):  
Catharine C. Bulik ◽  
Pamela R. Tessier ◽  
Rebecca A. Keel ◽  
Christina A. Sutherland ◽  
David P. Nicolau
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Resistance Mechanisms ◽  
Infection Model ◽  
Gram Negative ◽  
Content Type ◽  
Comparison Groups ◽  
Gram Negative Organisms

ABSTRACTCXA-101 is a novel antipseudomonal cephalosporin with enhanced activity against Gram-negative organisms displaying various resistance mechanisms. This study evaluates the efficacy of exposures approximating human percent free time above the MIC (%fT > MIC) of CXA-101 with or without tazobactam and piperacillin-tazobactam (TZP) against target Gram-negative organisms, including those expressing extended-spectrum β-lactamases (ESBLs). Sixteen clinical Gram-negative isolates (6Pseudomonas aeruginosaisolates [piperacillin-tazobactam MIC range, 8 to 64 μg/ml], 4Escherichia coliisolates (2 ESBL and 2 non-ESBL expressing), and 4Klebsiella pneumoniaeisolates (3 ESBL and 1 non-ESBL expressing) were used in an immunocompetent murine thigh infection model. After infection, groups of mice were administered doses of CXA-101 with or without tazobactam (2:1) designed to approximate the %fT > MIC observed in humans given 1 g of CXA-101 with or without tazobactam every 8 h as a 1-h infusion. As a comparison, groups of mice were administered piperacillin-tazobactam doses designed to approximate the %fT > MIC observed in humans given 4.5 g piperacillin-tazobactam every 6 h as a 30-min infusion. Predicted piperacillin-tazobactam %fT > MIC exposures of greater than 40% resulted in static to >1 log decreases in CFU in non-ESBL-expressing organisms with MICs of ≤32 μg/ml after 24 h of therapy. Predicted CXA-101 with or without tazobactam %fT > MIC exposures of ≥37.5% resulted in 1- to 3-log-unit decreases in CFU in non-ESBL-expressing organisms, with MICs of ≤16 μg/ml after 24 h of therapy. With regard to the ESBL-expressing organisms, the inhibitor combinations showed enhanced CFU decreases versus CXA-101 alone. Due to enhancedin vitropotency and resultant increasedin vivoexposure, CXA-101 produced statistically significant reductions in CFU in 9 isolates compared with piperacillin-tazobactam. The addition of tazobactam to CXA-101 produced significant reductions in CFU for 7 isolates compared with piperacillin-tazobactam. Overall, human simulated exposures of CXA-101 with or without tazobactam demonstrated improved efficacy versus piperacillin-tazobactam.

scholarly journals Expected Plazomicin Susceptibility in India Based on the Prevailing Aminoglycoside Resistance Mechanisms in Gram-Negative Organisms Derived from Whole-Genome Sequencing

2020 ◽  
Vol 38 (3-4) ◽  
pp. 313-318
Author(s):  
Agila Kumari Pragasam ◽  
S.Lydia Jennifer ◽  
Dhanalakshmi Solaimalai ◽  
Dhiviya Prabaa Muthuirulandi Sethuvel ◽  
Tanya Rachel ◽  
...  
Keyword(s):  
Whole Genome Sequencing ◽  
Genome Sequencing ◽  
Resistance Mechanisms ◽  
Whole Genome ◽  
Aminoglycoside Resistance ◽  
Gram Negative ◽  
Gram Negative Organisms

scholarly journals National Surveillance of Antimicrobial Susceptibility of Bacteremic Gram-Negative Bacteria with Emphasis on Community-Acquired Resistant Isolates: Report from the 2019 Surveillance of Multicenter Antimicrobial Resistance in Taiwan (SMART)

2020 ◽  
Vol 64 (10) ◽  
Author(s):  
Po-Yu Liu ◽  
Yu-Lin Lee ◽  
Min-Chi Lu ◽  
Pei-Lan Shao ◽  
Po-Liang Lu ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Pseudomonas Aeruginosa ◽  
Antimicrobial Resistance ◽  
Klebsiella Pneumoniae ◽  
Gram Negative Bacteria ◽  
National Surveillance ◽  
Gram Negative ◽  
Content Type ◽  
E Coli ◽  
Carbapenem Resistant

ABSTRACT A multicenter collection of bacteremic isolates of Escherichia coli (n = 423), Klebsiella pneumoniae (n = 372), Pseudomonas aeruginosa (n = 300), and Acinetobacter baumannii complex (n = 199) was analyzed for susceptibility. Xpert Carba-R assay and sequencing for mcr genes were performed for carbapenem- or colistin-resistant isolates. Nineteen (67.8%) carbapenem-resistant K. pneumoniae (n = 28) and one (20%) carbapenem-resistant E. coli (n = 5) isolate harbored blaKPC (n = 17), blaOXA-48 (n = 2), and blaVIM (n = 1) genes.

Antimicrobial Resistance and Association with Class 1 Integrons in Escherichia coli Isolated from Turkey Meat Products

2008 ◽  
Vol 71 (8) ◽  
pp. 1679-1684 ◽  
Author(s):  
M. L. KHAITSA ◽  
J. OLOYA ◽  
D. DOETKOTT ◽  
R. KEGODE
Keyword(s):  
Escherichia Coli ◽  
Antimicrobial Resistance ◽  
Antimicrobial Agents ◽  
Population Attributable Fraction ◽  
Meat Products ◽  
Resistance Mechanisms ◽  
E Coli ◽  
Class 1 Integrons ◽  
Turkey Meat ◽  
Class 1

The objective of this study was to quantify the role of class 1 integrons in antimicrobial resistance in Escherichia coli isolated from turkey meat products purchased from retail outlets in the Midwestern United States. Of 242 E. coli isolates, 41.3% (102 of 242) tested positive for class 1 integrons. A significant association was shown between presence of class 1 integrons in E. coli isolates and the resistance to tetracycline, ampicillin, streptomycin, gentamicin, sulfisoxazole, and trimethoprim-sulfamethoxazole. Attributable risk analysis revealed that for every 100 E. coli isolates carrying class 1 integrons, resistance was demonstrated for ampicillin (22%), gentamycin (48%), streptomycin (29%), sulfisoxazole (40%), trimethoprimsulfamethoxazole (7%), and tetracycline (26%). Non–integron-related antimicrobial resistance was demonstrated for ampicillin (65%), gentamycin (16.9%), streptomycin (42.1%), sulfisoxazole (35.8%), and tetracycline (49.7%). Population-attributable fraction analysis showed that class 1 integrons accounted for the following resistances: gentamycin, 71% (50 of 71), amoxicillin–clavulanic acid, 19.6% (6 of 33), nalidixic acid, 34% (7 of 21), streptomycin, 28% (30 of 107), sulfisoxazole, 38% (40 of 106), and tetracycline, 14%, (26 of 185). In conclusion, although class 1 integrons have been implicated in resistance to antimicrobial agents, other non–integron resistance mechanisms seem to play an important part.

scholarly journals High Prevalence of Antimicrobial Resistance Among Gram-Negative Isolated Bacilli in Intensive Care Units at a Tertiary-Care Hospital in Yucatán Mexico

Medicina ◽  
2019 ◽  
Vol 55 (9) ◽  
pp. 588 ◽  
Author(s):  
Andrés H. Uc-Cachón ◽  
Carlos Gracida-Osorno ◽  
Iván G. Luna-Chi ◽  
Jonathan G. Jiménez-Guillermo ◽  
Gloria M. Molina-Salinas
Keyword(s):  
Escherichia Coli ◽  
Intensive Care ◽  
Antimicrobial Resistance ◽  
Intensive Care Units ◽  
High Resistance ◽  
Tertiary Care Hospital ◽  
Tertiary Care ◽  
Care Hospital ◽  
Gram Negative ◽  
Resistance Rates

Background and Objectives: Antimicrobial resistance (AMR) is increasing worldwide and imposes significant life-threatening risks to several different populations, especially to those in intensive care units (ICU). The most commonly isolated organisms in ICU comprise gram-negative bacilli (GNB), and these represent a leading cause of serious infections. This study was conducted to describe the prevalence of resistance in GNB isolated from patients in adults, pediatric, and neonatal ICU in a tertiary-care hospital in Mérida, Mexico. Materials and Methods: A retrospective study was done on samples collected in Neonatal (NICU), Pediatric (PICU) and Adult (AICU) ICU of Unidad Médica de Alta Especialidad, Instituto Mexicano del Seguro Social in Mérida, México. The identification of isolates and antimicrobial susceptibility testing were performed using an automated system. Results: A total of 517 GNB strains were isolated. The most common positive culture was bronchial secretions. Pseudomonas aeruginosa was the prevalent pathogen in NICU and PICU, whereas Escherichia coli was common in the AICU. Overall, GNB exhibited a high resistance rates for Ampicillin (95.85%), Cefuroxime (84.17%), Piperacillin (82.93%), Cefotaxime (78.07%), Ceftriaxone (77.41%), Aztreonam (75.23%), Cefazolin (75.00%), and Ceftazidime (73.19%). There are significant differences in the resistance rates of GNB from different ICUs for penicillins, cephalosporins, carbapenems and fluoroquinolones drugs. Escherichia coli (multidrug-resistant [MDR] = 91.57%, highly resistant microorganisms [HRMO] = 90.36%) and Acinetobacter baumannii (MDR = 86.79%, HRMO = 83.02%) exhibited the highest percentage of MDR and HRMO profiles. The prevalence of the extended-spectrum beta-lactamases (ESBL)-producing isolates was 83.13% in E. coli, 78.84% in Klebsiella pneumoniae, and 66.67% in Proteus mirabilis, respectively. Conclusions: The high resistance rates to drugs were exhibited by our GNB isolates. Continuous surveillance and control of the use of antimicrobials are urgently needed to reduce the emergence and spreading of MDR, HRMO, and/or ESBL-producing bacilli.

Inactivation of chloramphenicol by Gram-negative microorganisms

1968 ◽  
Vol 14 (8) ◽  
pp. 891-899 ◽  
Author(s):  
David Sompolinsky ◽  
Ruth Ziegler-Schlomowitz ◽  
Dora Herczog
Keyword(s):  
Escherichia Coli ◽  
Growth Medium ◽  
Minimal Medium ◽  
Resistance Factor ◽  
The Other ◽  
Gram Negative ◽  
Resistant Strains ◽  
Gram Negative Organisms ◽  
High Level ◽  
Level Resistance

Two derivative strains of Escherichia coli with high-level resistance to chloramphenicol, one carrying an episomal resistance factor and the other a chromosomal mutant, were both shown to be potent inactivators of the drug. When 1 mM chloramphenicol was added to an exponential culture in minimal medium, growth was halted until 85–90% of the drug was inactivated by acylation. At this state the drug was essentially monoacylated. During and after growth, esterification of the second alcoholic group occurred, though at a slower rate. Arylamines, in amounts up to 10% of chloramphenicol equivalents, were demonstrated in the growth medium after 1–3 days' incubation.With an acetateless mutant of Escherichia coli K12, carrying a resistance factor, it was shown that 5–6 moles of acetate was consumed for every mole of chloramphenicol acylated.Inactivation of chloramphenicol by Gram-negative organisms from infections in hospitalized patients was also examined. Among 103 strains susceptible to chloramphenicol, none produced considerable amounts of chloramphenicol esters. The same was the case with 14 resistant strains of Pseudomonas. Of 134 other resistant organisms examined, including strains of Escherichia, Proteus, Klebsiella, Salmonella, and Shigella, 133 were producers of chloramphenicol esters, and in most cases the drug was partly or entirely diacylated.

scholarly journals Polar Localization of the Autotransporter Family of Large Bacterial Virulence Proteins

2006 ◽  
Vol 188 (13) ◽  
pp. 4841-4850 ◽  
Author(s):  
Sumita Jain ◽  
Peter van Ulsen ◽  
Inga Benz ◽  
M. Alexander Schmidt ◽  
Rachel Fernandez ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Shigella Flexneri ◽  
Bacterial Pathogen ◽  
Gram Negative ◽  
Virulence Proteins ◽  
Host Interactions ◽  
Polar Localization ◽  
Associated Proteins ◽  
Molecular Information ◽  
Gram Negative Organisms

ABSTRACT Autotransporters are an extensive family of large secreted virulence-associated proteins of gram-negative bacteria. Secretion of such large proteins poses unique challenges to bacteria. We demonstrate that autotransporters from a wide variety of rod-shaped pathogens, including IcsA and SepA of Shigella flexneri, AIDA-I of diffusely adherent Escherichia coli, and BrkA of Bordetella pertussis, are localized to the bacterial pole. The restriction of autotransporters to the pole is dependent on the presence of a complete lipopolysaccharide (LPS), consistent with known effects of LPS composition on membrane fluidity. Newly synthesized and secreted BrkA is polar even in the presence of truncated LPS, and all autotransporters examined are polar in the cytoplasm prior to secretion. Together, these findings are consistent with autotransporter secretion occurring at the poles of rod-shaped gram-negative organisms. Moreover, NalP, an autotransporter of spherically shaped Neisseria meningitidis contains the molecular information to localize to the pole of Escherichia coli. In N. meningitidis, NalP is secreted at distinct sites around the cell. These data are consistent with a model in which the secretion of large autotransporters occurs via specific conserved pathways located at the poles of rod-shaped bacteria, with profound implications for the underlying physiology of the bacterial cell and the nature of bacterial pathogen-host interactions.

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