scholarly journals Detection of Carbapenemase Production in a Collection of Enterobacteriaceae with Characterized Resistance Mechanisms from Clinical and Environmental Origins by Use of Both Carba NP and Blue-Carba Tests: TABLE 1

2015 ◽  
Vol 54 (2) ◽  
pp. 464-466 ◽  
Author(s):  
Sergio García-Fernández ◽  
María-Isabel Morosini ◽  
Desirèe Gijón ◽  
Lorena Beatobe ◽  
Patricia Ruiz-Garbajosa ◽  
...  
Keyword(s):  
High Sensitivity ◽  
Cost Effective ◽  
Multidrug Resistant ◽  
Resistance Mechanisms ◽  
Rapid Screening ◽  
Resistant Bacteria ◽  
Screening Methods ◽  
Routine Laboratory ◽  
Multidrug Resistant Bacteria ◽  
Content Type

Rapid-screening methods to confirm the presence of resistance mechanisms in multidrug-resistant bacteria are currently recommended. Carba NP and Blue-Carba tests were evaluated in carbapenemase-producingEnterobacteriaceaefrom hospital (n= 102) and environmental (n= 57) origins for detecting the different molecular classes among them. Both methods showed to be fast and cost-effective, with high sensitivity (98% to 100%) and specificity (100%), and may be easily introduced in the routine laboratory.

scholarly journals Environmental Spread of New Delhi Metallo-β-Lactamase-1-Producing Multidrug-Resistant Bacteria in Dhaka, Bangladesh

2017 ◽  
Vol 83 (15) ◽  
Author(s):  
Mohammad Aminul Islam ◽  
Moydul Islam ◽  
Rashedul Hasan ◽  
M. Iqbal Hossain ◽  
Ashikun Nabi ◽  
...  
Keyword(s):  
Antibiotic Resistance ◽  
Resistance Genes ◽  
Tap Water ◽  
Antibiotic Resistance Genes ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
New Delhi ◽  
Multidrug Resistant Bacteria ◽  
Content Type ◽  
Wastewater Samples

ABSTRACT Resistance to carbapenem antibiotics through the production of New Delhi metallo-β-lactamase-1 (NDM-1) constitutes an emerging challenge in the treatment of bacterial infections. To monitor the possible source of the spread of these organisms in Dhaka, Bangladesh, we conducted a comparative analysis of wastewater samples from hospital-adjacent areas (HAR) and from community areas (COM), as well as public tap water samples, for the occurrence and characteristics of NDM-1-producing bacteria. Of 72 HAR samples tested, 51 (71%) samples were positive for NDM-1-producing bacteria, as evidenced by phenotypic tests and the presence of the bla NDM-1 gene, compared to 5 of 41 (12.1%) samples from COM samples (P < 0.001). All tap water samples were negative for NDM-1-producing bacteria. Klebsiella pneumoniae (44%) was the predominant bacterial species among bla NDM-1-positive isolates, followed by Escherichia coli (29%), Acinetobacter spp. (15%), and Enterobacter spp. (9%). These bacteria were also positive for one or more other antibiotic resistance genes, including bla CTX-M-1 (80%), bla CTX-M-15 (63%), bla TEM (76%), bla SHV (33%), bla CMY-2 (16%), bla OXA-48-like (2%), bla OXA-1 (53%), and bla OXA-47-like (60%) genes. Around 40% of the isolates contained a qnr gene, while 50% had 16S rRNA methylase genes. The majority of isolates hosted multiple plasmids, and plasmids of 30 to 50 MDa carrying bla NDM-1 were self-transmissible. Our results highlight a number of issues related to the characteristics and source of spread of multidrug-resistant bacteria as a potential public health threat. In view of the existing practice of discharging untreated liquid waste into the environment, hospitals in Dhaka city contribute to the potential dissemination of NDM-1-producing bacteria into the community. IMPORTANCE Infections caused by carbapenemase-producing Enterobacteriaceae are extremely difficult to manage due to their marked resistance to a wide range of antibiotics. NDM-1 is the most recently described carbapenemase, and the bla NDM-1 gene, which encodes NDM-1, is located on self-transmissible plasmids that also carry a considerable number of other antibiotic resistance genes. The present study shows a high prevalence of NDM-1-producing organisms in the wastewater samples from hospital-adjacent areas as a potential source for the spread of these organisms to community areas in Dhaka, Bangladesh. The study also examines the characteristics of the isolates and their potential to horizontally transmit the resistance determinants. The significance of our research is in identifying the mode of spread of multiple-antibiotic-resistant organisms, which will allow the development of containment measures, leading to broader impacts in reducing their spread to the community.

Resistance to nitrofurantoin is an indicator of extensive drug-resistant (XDR) Enterobacteriaceae

2021 ◽  
Vol 70 (4) ◽  
Author(s):  
Balaram Khamari ◽  
Prakash Kumar ◽  
Bulagonda Eswarappa Pradeep
Keyword(s):  
Antimicrobial Agents ◽  
Efflux Pump ◽  
Treatment Options ◽  
Strong Association ◽  
Multidrug Resistant ◽  
Resistance Mechanisms ◽  
Resistant Bacteria ◽  
Drug Resistant ◽  
Content Type ◽  
Link Type

Introduction. Nitrofurantoin is one of the preferred antibiotics in the treatment of uropathogenic multidrug-resistant (MDR) infections. However, resistance to nitrofurantoin in extensively drug-resistant (XDR) bacteria has severely limited the treatment options. Gap statement. Information related to co-resistance or collateral sensitivity (CS) with reference to nitrofurantoin resistant bacteria is limited. Aim. To study the potential of nitrofurantoin resistance as an indicator of the XDR phenotype in Enterobacteriaceae . Methods. One hundred (45 nitrofurantoin-resistant, 21 intermediately resistant and 34 nitrofurantoin-susceptible) Enterobacteriaceae were analysed in this study. Antibiotic susceptibility testing (AST) against nitrofurantoin and 17 other antimicrobial agents across eight different classes was performed by using the Vitek 2.0 system. The isolates were screened for the prevalence of acquired antimicrobial resistance (AMR) and efflux pump genes by PCR. Results. In total, 51 % of nitrofurantoin-resistant and 28 % of intermediately nitrofurantoin resistant isolates exhibited XDR characteristics, while only 3 % of nitrofurantoin-sensitive isolates were XDR (P=0.0001). Significant co-resistance was observed between nitrofurantoin and other tested antibiotics (β-lactam, cephalosporin, carbapenem, aminoglycoside and tetracycline). Further, the prevalence of AMR and efflux pump genes was higher in the nitrofurantoin-resistant strains compared to the susceptible isolates. A strong association was observed between nitrofurantoin resistance and the presence of bla PER-1, bla NDM-1, bla OXA-48, ant(2) and oqxA-oqxB genes. Tigecycline (84 %) and colistin (95 %) were the only antibiotics to which the majority of the isolates were susceptible. Conclusion. Nitrofurantoin resistance could be an indicator of the XDR phenotype among Enterobacteriaceae , harbouring multiple AMR and efflux pump genes. Tigecycline and colistin are the only antibiotics that could be used in the treatment of such XDR infections. A deeper understanding of the co-resistance mechanisms in XDR pathogens and prescription of AST-based appropriate combination therapy may help mitigate this problem.

Polymicrobial multidrug-resistant bacteria isolated from street vended fresh fruit juices in Pakistan

2018 ◽  
Vol 120 (6) ◽  
pp. 1358-1365
Author(s):  
Muhammad Hussnain Siddique ◽  
Muhammad Usman Qamar ◽  
Sumreen Hayat ◽  
Bilal Aslam ◽  
Habibullah Nadeem ◽  
...  
Keyword(s):  
Public Health ◽  
Multidrug Resistant ◽  
Fruit Juices ◽  
Fresh Fruit ◽  
Resistant Bacteria ◽  
Local Market ◽  
Multidrug Resistant Bacteria ◽  
Content Type ◽  
Preliminary Identification ◽  
Surface Spread

Purpose The purpose of this paper is to evaluate the prevalence and antibiograms of bacteria isolated from various fresh fruit juices at a local market in Faisalabad. Design/methodology/approach Fresh fruit juice samples (n=125) were randomly collected using aseptic technique. Each sample (10 mL) was serially diluted with 90 mL of sterile peptone water, from 1×10−1 to 1×10−5. Each dilution was then used to inoculate nutrient agar by surface spread plating. Aerobic colony counts (ACCs) were determined by colony counting. The isolates were sub-cultured on blood and MacConkey agar. Preliminary identification was achieved on the basis of colony morphology and culture characteristic, and confirmed by API® 20E, 20NE, and API® Staph testing. Antimicrobial susceptibility testing was carried out using the Kirby-Bauer disk diffusion assay, per CLSI 2015 guidelines. Findings The mean ACC ranged from 2.0×106 CFU/mL to 4.93×106 CFU/mL, with the highest ACC determined for orange juice. Overall, 153 polymicrobial were identified in 125 samples; 103 of these were Gram-negative rods (GNR) and 28 were Gram-positive cocci (GPC). Escherichia coli (n=38), Klebsiella pneumoniae (n=32) and Pseudomonas aeruginosa (n=24) were the predominant GNR; Staphylococcus aureus (n=28) was the predominant GPC. Antibiogram analysis revealed that all GNR were resistant to ampicillin. However, most E. coli isolates were resistant to ceftazidime (72.4 percent of isolates), and ceftriaxone and cefepime (68.9 percent), while most K. pneumoniae isolates were resistant to cefepime (72 percent) and ceftriaxone (64 percent). All S. aureus isolates were resistant to penicillin, while most (64 percent) were resistant to piperacillin; the most effective drugs against bacteria were vancomycin and imipenem. Practical implications The findings suggest that the local government regulatory food and public health authorities should take immediate emergency measures. Appropriate surveillance studies and periodic monitoring of food items should be regularly performed to safeguard public health. Originality/value The current study revealed the prevalence of multidrug-resistant bacteria in freshly prepared fruit juices sold by local street vendors.

scholarly journals Species Diversity of Environmental GIM-1-Producing Bacteria Collected during a Long-Term Outbreak

2016 ◽  
Vol 82 (12) ◽  
pp. 3605-3610 ◽  
Author(s):  
Andreas F. Wendel ◽  
Sofija Ressina ◽  
Susanne Kolbe-Busch ◽  
Klaus Pfeffer ◽  
Colin R. MacKenzie
Keyword(s):  
Resistance Genes ◽  
Multidrug Resistant ◽  
Hospital Environment ◽  
Resistant Bacteria ◽  
Environmental Sampling ◽  
Gram Negative Bacteria ◽  
Multidrug Resistant Bacteria ◽  
Gram Negative ◽  
Content Type

ABSTRACTReports of outbreaks concerning carbapenemase-producing Gram-negative bacteria in which the main source of transmission is the hospital environment are increasing. This study describes the results of environmental sampling in a protracted polyspecies metallo-beta-lactamase GIM-1 outbreak driven by plasmids and bacterial clones ofEnterobacter cloacaeandPseudomonas aeruginosain a tertiary care center. Environmental sampling targeting wet locations (especially sinks) was carried out on a surgical intensive care unit and on a medical ward on several occasions in 2012 and 2013. We were able to demonstrate 43blaGIM-1-carrying bacteria (mainly nonfermenters but alsoEnterobacteriaceae) that were either related or unrelated to clinical strains in 30 sinks and one hair washbasin. GIM-1 was found in 12 different species, some of which are described here as carriers of GIM-1. Forty out of 43 bacteria displayed resistance to carbapenems and, in addition, to various non-beta-lactam antibiotics. Colistin resistance was observed in twoE. cloacaeisolates with MICs above 256 mg/liter. TheblaGIM-1gene was harbored in 12 different class 1 integrons, some without the typical 3′ end. TheblaGIM-1gene was localized on plasmids in five isolates.In vitroplasmid transfer by conjugation was successful in one isolate. The environment, with putatively multispecies biofilms, seems to be an important biological niche for multidrug-resistant bacteria and resistance genes. Biofilms may serve as a “melting pot” for horizontal gene transfer, for dissemination into new species, and as a reservoir to propagate future hospital outbreaks.IMPORTANCEIn Gram-negative bacteria, resistance to the clinically relevant broad-spectrum carbapenem antibiotics is a major public health concern. Major reservoirs for these resistant organisms are not only the gastrointestinal tracts of animals and humans but also the (hospital) environment. Due to the difficulty in eradicating biofilm formation in the latter, a sustained dissemination of multidrug-resistant bacteria from the environment can occur. In addition, horizontal transfer of resistance genes on mobile genetic elements within biofilms adds to the total “resistance gene pool” in the environment. To gain insight into the transmission pathways of a rare and locally restricted carbapenemases resistance gene (blaGIM-1), we analyzed the genetic background of theblaGIM-1gene in environmental bacteria during a long-term polyspecies outbreak in a German hospital.

scholarly journals Post-antibiotic era in hemodialysis? Two case reports of simultaneous colonization and bacteremia by multidrug-resistant bacteria

2020 ◽  
Author(s):  
Johanna M. Vanegas ◽  
Lorena Salazar-Ospina ◽  
Gustavo A. Roncancio ◽  
Julián Builes ◽  
Judy Natalia Jiménez
Keyword(s):  
Pseudomonas Aeruginosa ◽  
Bacterial Infections ◽  
Case Reports ◽  
Multidrug Resistant ◽  
Resistance Mechanisms ◽  
Control Measures ◽  
Resistant Bacteria ◽  
Multidrug Resistant Bacteria ◽  
E Coli ◽  
Carbapenem Resistant

ABSTRACT The emergence of resistance mechanisms not only limits the therapeutic options for common bacterial infections but also worsens the prognosis in patients who have conditions that increase the risk of bacterial infections. Thus, the effectiveness of important medical advances that seek to improve the quality of life of patients with chronic diseases is threatened. We report the simultaneous colonization and bacteremia by multidrug-resistant bacteria in two hemodialysis patients. The first patient was colonized by carbapenem- and colistin-resistant Klebsiella pneumoniae, carbapenem-resistant Pseudomonas aeruginosa, and methicillin-resistant Staphylococcus aureus (MRSA). The patient had a bacteremia by MRSA, and molecular typing methods confirmed the colonizing isolate was the same strain that caused infection. The second case is of a patient colonized by extended-spectrum beta-lactamases (ESBL)-producing Escherichia coli and carbapenem-resistant Pseudomonas aeruginosa. During the follow-up period, the patient presented three episodes of bacteremia, one of these caused by ESBL-producing E. coli. Molecular methods confirmed colonization by the same clone of ESBL-producing E. coli at two time points, but with a different genetic pattern to the strain isolated from the blood culture. Colonization by multidrug-resistant bacteria allows not only the spread of these microorganisms, but also increases the subsequent risk of infections with limited treatments options. In addition to infection control measures, it is important to establish policies for the prudent use of antibiotics in dialysis units.

scholarly journals Two Hits Are Better than One: Membrane-Active and DNA Binding-Related Double-Action Mechanism of NK-18, a Novel Antimicrobial Peptide Derived from Mammalian NK-Lysin

2012 ◽  
Vol 57 (1) ◽  
pp. 220-228 ◽  
Author(s):  
Jiexi Yan ◽  
Kairong Wang ◽  
Wen Dang ◽  
Ru Chen ◽  
Junqiu Xie ◽  
...  
Keyword(s):  
Antimicrobial Peptides ◽  
Cytotoxic T Cells ◽  
Multidrug Resistant ◽  
Chemotherapeutic Agents ◽  
Resistant Bacteria ◽  
Multidrug Resistant Bacteria ◽  
Content Type ◽  
New Strategy ◽  
Conventional Antibiotics ◽  
Double Targets

ABSTRACTThe extensive use and misuse of antibiotics in medicine result in the emergence of multidrug-resistant bacteria, creating an urgent need for the development of new chemotherapeutic agents. Nowadays, antimicrobial peptides are widely recognized as a class of promising candidates with activity against multidrug-resistant bacteria. NK-18 is a truncated peptide derived from NK-Lysin, an effector of cytotoxic T cells and natural killer cells. In this study, we studied the antibacterial mechanism of action of NK-18. The results revealed that NK-18 has potent antibacterial activity againstEscherichia coliandStaphylococcus aureus. According to our findings, NK-18 is membrane active and its target of action is not only the bacterial membrane but also the DNA in the cytoplasm. The double targets of NK-18 make it difficult for bacteria to generate resistance, which may present a new strategy to defend against multidrug-resistant bacteria and provide a new lead in the design of potent antimicrobial peptides with therapeutic application in the presence of increasing resistance to conventional antibiotics.

scholarly journals Abdominal Candidiasis Is a Hidden Reservoir of Echinocandin Resistance

2014 ◽  
Vol 58 (12) ◽  
pp. 7601-7605 ◽  
Author(s):  
Ryan K. Shields ◽  
M. Hong Nguyen ◽  
Ellen G. Press ◽  
Cornelius J. Clancy
Keyword(s):  
Candida Albicans ◽  
Candida Glabrata ◽  
Multidrug Resistant ◽  
Source Control ◽  
Resistant Bacteria ◽  
Multidrug Resistant Bacteria ◽  
Content Type ◽  
Echinocandin Resistance ◽  
Abdominal Candidiasis

ABSTRACTFKSmutantCandidaisolates were recovered from 24% (6/25) of abdominal candidiasis patients exposed to echinocandin.Candida glabrata(29%) andCandida albicans(14%) mutants were identified. Multidrug-resistant bacteria were recovered from 83% ofFKSmutant infections. Mutations were associated with prolonged echinocandin exposure (P= 0.01), breakthrough infections (P= 0.03), and therapeutic failures despite source control interventions (100%). Abdominal candidiasis is a hidden reservoir for the emergence of echinocandin-resistantCandida.

scholarly journals A Whole-Cell Screen Identifies Small Bioactives That Synergize with Polymyxin and Exhibit Antimicrobial Activities against Multidrug-Resistant Bacteria

2019 ◽  
Vol 64 (3) ◽  
Author(s):  
Shawn M. Zimmerman ◽  
Audrey-Ann J. Lafontaine ◽  
Carmen M. Herrera ◽  
Amanda B. Mclean ◽  
M. Stephen Trent
Keyword(s):  
Bacterial Infections ◽  
Large Scale ◽  
The United States ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Synergistic Activity ◽  
Multidrug Resistant Bacteria ◽  
Gram Negative ◽  
Content Type ◽  
Eskape Pathogens

ABSTRACT The threat of diminished antibiotic discovery has global health care in crisis. In the United States, it is estimated each year that over 2 million bacterial infections are resistant to first-line antibiotic treatments and cost in excess of 20 billion dollars. Many of these cases result from infection with the ESKAPE pathogens (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa, and Enterobacter species), which are multidrug-resistant bacteria that often cause community- and hospital-acquired infections in both healthy and immunocompromised patients. Physicians have turned to last-resort antibiotics like polymyxins to tackle these pathogens, and as a consequence, polymyxin resistance has emerged and is spreading. Barring the discovery of new antibiotics, another route to successfully mitigate polymyxin resistance is to identify compounds that can complement the existing arsenal of antibiotics. We recently designed and performed a large-scale robotic screen to identify 43 bioactive compounds that act synergistically with polymyxin B to inhibit the growth of polymyxin-resistant Escherichia coli. Of these 43 compounds, 5 lead compounds were identified and characterized using various Gram-negative bacterial organisms to better assess their synergistic activity with polymyxin. Several of these compounds reduce polymyxin to an MIC of <2 μg/ml against polymyxin-resistant and polymyxin-heteroresistant Gram-negative pathogens. Likewise, four of these compounds exhibit antimicrobial activity against Gram-positive bacteria, one of which rapidly eradicated methicillin-resistant Staphylococcus aureus. We present multiple first-generation (i.e., not yet optimized) compounds that warrant further investigation and optimization, since they can act both synergistically with polymyxin and also as lone antimicrobials for combating ESKAPE pathogens.

scholarly journals Molecular Mechanisms of Bacterial Resistance to Metal and Metal Oxide Nanoparticles

2019 ◽  
Vol 20 (11) ◽  
pp. 2808 ◽  
Author(s):  
Nereyda Niño-Martínez ◽  
Marco Felipe Salas Orozco ◽  
Gabriel-Alejandro Martínez-Castañón ◽  
Fernando Torres Méndez ◽  
Facundo Ruiz
Keyword(s):  
Metal Oxide ◽  
Molecular Mechanisms ◽  
Bacterial Resistance ◽  
Bacterial Species ◽  
Metal Oxide Nanoparticles ◽  
Multidrug Resistant ◽  
Resistance Mechanisms ◽  
Resistant Bacteria ◽  
Oxide Nanoparticles ◽  
Multidrug Resistant Bacteria

The increase in bacterial resistance to one or several antibiotics has become a global health problem. Recently, nanomaterials have become a tool against multidrug-resistant bacteria. The metal and metal oxide nanoparticles are one of the most studied nanomaterials against multidrug-resistant bacteria. Several in vitro studies report that metal nanoparticles have antimicrobial properties against a broad spectrum of bacterial species. However, until recently, the bacterial resistance mechanisms to the bactericidal action of the nanoparticles had not been investigated. Some of the recently reported resistance mechanisms include electrostatic repulsion, ion efflux pumps, expression of extracellular matrices, and the adaptation of biofilms and mutations. The objective of this review is to summarize the recent findings regarding the mechanisms used by bacteria to counteract the antimicrobial effects of nanoparticles.

scholarly journals Multidrug-resistant bacteria as intestinal colonizers and evolution of intestinal colonization in healthy university students in Portugal

2020 ◽  
Author(s):  
Raquel Mota ◽  
Marisa Pinto ◽  
Josman Palmeira ◽  
Daniela Gonçalves ◽  
Helena Ferreira
Keyword(s):  
University Students ◽  
Type Species ◽  
Multidrug Resistant ◽  
Resistant Bacteria ◽  
Intestinal Colonization ◽  
Multidrug Resistant Bacteria ◽  
Gram Negative ◽  
Content Type ◽  
E Coli ◽  
Link Type

Multidrug-resistant bacteria have been increasingly described in healthcare institutions, however community resistance also seems to be emerging. Escherichia coli an intestinal commensal bacteria, is also a pathogen and represents an important intestinal reservoir of resistance. Our aim was the study of the intestinal colonization and of the persistence of antibiotic resistant intestinal bacteria in healthy university students of Porto, in the north of Portugal. Samples from 30 university students were collected and analysed. Two E. coli isolates were randomly obtained from each student and Gram-negative bacilli resistant to antibiotics were studied. In addition, we evaluated changes in the Gram-negative intestinal colonization of ten university students in a short period of time. Molecular characterization showed a high presence of bla TEM in commensal E. coli . Gram-negative bacteria with intrinsic and extrinsic resistance were isolated, namely Pseudomonas spp., Enterobacter spp. and Pantoea spp. We isolated three ESBL-producing E. coli from two students. These isolates showed bla CTX-M group 1 (n=1), bla CTX-M group 9 (n=2), bla TEM (n=2), bla SHV (n=1) and tetA (n=2) genes. Additionally, they showed specific virulence factors and conjugational transfer of antibiotic resistance and virulence genes. One Pseudomonas spp. isolate resistant to carbapenems was detected colonizing one student. Our results confirm that healthy young adults may be colonized with commensals showing clinically relevant antibiotic resistance mechanisms, creating a risk of silent spread of these bacteria in the community.

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