scholarly journals Potentiating antibiotic treatment using fitness-neutral gene expression perturbations

2019 ◽  
Author(s):  
Peter B. Otoupal ◽  
Keesha E. Erickson ◽  
Kristen A. Eller ◽  
Jocelyn Campos ◽  
Thomas R. Aunins ◽  
...  
Keyword(s):  
Gene Expression ◽  
Antibiotic Treatment ◽  
Bacterial Infections ◽  
Gene Knockout ◽  
Multidrug Resistant ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Neutral Gene ◽  
Targeted Gene Expression ◽  
Intracellular Infections

AbstractThe rapid proliferation of multidrug-resistant (MDR) bacteria poses a critical threat to human health, for which new antimicrobial strategies are desperately needed. Here we outline a strategy for combating bacterial infections by administering fitness neutral gene expression perturbations as co-therapies to potentiate antibiotic lethality. We systematically explored the fitness of 270 gene knockout-drug combinations in Escherichia coli, identifying 114 synergistic interactions. Genes revealed in this screen were subsequently perturbed at the transcriptome level via multiplexed CRISPR-dCas9 interference to induce antibiotic synergy. These perturbations successfully sensitized E. coli to antibiotic treatment without imposing a separate fitness cost. We next administered these fitness neutral gene perturbations as co-therapies to potentiate antibiotic killing of Salmonella enterica in intracellular infections of HeLa epithelial cells, demonstrating therapeutic applicability. Finally, we utilized these results to design peptide nucleic acid (PNA) co-therapies for targeted gene expression reduction in four MDR, clinically isolated bacteria. Two isolates of Klebsiella pneumoniae and E. coli were each exposed to PNAs targeting homologs of the genes csgD, fnr, recA and acrA in the presence of sub-minimal inhibitory concentrations of trimethoprim. We successfully increased each strain’s susceptibility to trimethoprim treatment and identified eight cases in which re-sensitization occurred without a direct fitness impact of the PNA on MDR strains. Our results highlight a promising approach for combating MDR bacteria which could extend the utility of our current antibiotic arsenal.

scholarly journals Potentiating antibiotic efficacy via perturbation of non-essential gene expression

2021 ◽  
Vol 4 (1) ◽  
Author(s):  
Peter B. Otoupal ◽  
Kristen A. Eller ◽  
Keesha E. Erickson ◽  
Jocelyn Campos ◽  
Thomas R. Aunins ◽  
...  
Keyword(s):  
Gene Expression ◽  
Essential Gene ◽  
Gene Knockout ◽  
Multidrug Resistant ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Synergistic Interactions ◽  
Neutral Gene ◽  
Transcriptomic Level ◽  
Antibiotic Efficacy

AbstractProliferation of multidrug-resistant (MDR) bacteria poses a threat to human health, requiring new strategies. Here we propose using fitness neutral gene expression perturbations to potentiate antibiotics. We systematically explored 270 gene knockout-antibiotic combinations in Escherichia coli, identifying 90 synergistic interactions. Identified gene targets were subsequently tested for antibiotic synergy on the transcriptomic level via multiplexed CRISPR-dCas9 and showed successful sensitization of E. coli without a separate fitness cost. These fitness neutral gene perturbations worked as co-therapies in reducing a Salmonella enterica intracellular infection in HeLa. Finally, these results informed the design of four antisense peptide nucleic acid (PNA) co-therapies, csgD, fnr, recA and acrA, against four MDR, clinically isolated bacteria. PNA combined with sub-minimal inhibitory concentrations of trimethoprim against two isolates of Klebsiella pneumoniae and E. coli showed three cases of re-sensitization with minimal fitness impacts. Our results highlight a promising approach for extending the utility of current antibiotics.

scholarly journals Three-Year Trend in Escherichia coli Antimicrobial Resistance among Children’s Urine Cultures in an Italian Metropolitan Area

Children ◽  
2021 ◽  
Vol 8 (7) ◽  
pp. 597
Author(s):  
Luca Pierantoni ◽  
Laura Andreozzi ◽  
Simone Ambretti ◽  
Arianna Dondi ◽  
Carlotta Biagi ◽  
...  
Keyword(s):  
Escherichia Coli ◽  
Metropolitan Area ◽  
Bacterial Infections ◽  
Asymptomatic Bacteriuria ◽  
Multidrug Resistant ◽  
Resistance Rate ◽  
First Line ◽  
E Coli ◽  
First Line Therapy ◽  
Tract Infections

Urinary tract infections (UTIs) are among the most common bacterial infections in children, and Escherichia coli is the main pathogen responsible. Several guidelines, including the recently updated Italian guidelines, recommend amoxicillin-clavulanic acid (AMC) as a first-line antibiotic therapy in children with febrile UTIs. Given the current increasing rates of antibiotic resistance worldwide, this study aimed to investigate the three-year trend in the resistance rate of E. coli isolated from pediatric urine cultures (UCs) in a metropolitan area of northern Italy. We conducted a retrospective review of E. coli-positive, non-repetitive UCs collected in children aged from 1 month to 14 years, regardless of a diagnosis of UTI, catheter colonization, urine contamination, or asymptomatic bacteriuria. During the study period, the rate of resistance to AMC significantly increased from 17.6% to 40.2% (p < 0.001). Ciprofloxacin doubled its resistance rate from 9.1% to 16.3% (p = 0.007). The prevalence of multidrug-resistant E. coli rose from 3.9% to 9.2% (p = 0.015). The rate of resistance to other considered antibiotics remained stable, as did the prevalence of extended spectrum beta-lactamases and extensively resistant E. coli among isolates. These findings call into question the use of AMC as a first-line therapy for pediatric UTIs in our population, despite the indications of recent Italian guidelines.

scholarly journals Prevalence of Colistin-Resistant, Carbapenem-Hydrolyzing Proteobacteria in Hospital Water Bodies and Out-Falls of West Bengal, India

2020 ◽  
Vol 17 (3) ◽  
pp. 1007
Author(s):  
Taniya Bardhan ◽  
Madhurima Chakraborty ◽  
Bornali Bhattacharjee
Keyword(s):  
Escherichia Coli ◽  
Bacterial Infections ◽  
West Bengal ◽  
Environmental Water ◽  
Multidrug Resistant ◽  
P Value ◽  
Hospital Wastewater ◽  
E Coli ◽  
Predominant Species ◽  
Carbapenemase Gene

Indiscriminate use of antibiotics has resulted in a catastrophic increase in the levels of antibiotic resistance in India. Hospitals treat critical bacterial infections and thus can serve as reservoirs of multidrug resistant (MDR) bacteria. Hence, this study was conducted to gauge the prevalence patterns of MDR bacteria in hospital wastewater. Water samples collected from 11 hospitals and 4 environmental sources belonging to 5 most-densely populated districts of West Bengal, India were grown on MacConkey and Eosin Methylene Blue agar. A total of 84 (hospital-associated = 70, environmental water sources = 14) isolates were characterized. The predominant species found in water from hospital-associated areas (HAA) were Acinetobacter baumannii (22.9%), Escherichia coli (28.6 %), and Klebsiella pneumoniae (25.7%). Greater than 75% of the HAA isolates were found to be mcr-1 gene negative and colistinresistant. Meropenem non-susceptibility was also high among the HAA isolates at 58.6%, with the presence of the carbapenemase gene and blaNDM in 67.1% of the non-susceptible isolates. Among the three predominant species, significantly higher numbers of E. coli isolates were found to be non-susceptible to meropenem ((80%), p-value = 0.00432) and amikacin (AK (90%), p-value = 0.00037). This study provides evidence for the presence of high numbers of colistin-resistant and carbapenem-hydrolyzing Proteobacteriain hospital wastewater.

scholarly journals Impact of Healthcare-Associated Infections on Length of Stay: A Study in 68 Hospitals in China

2019 ◽  
Vol 2019 ◽  
pp. 1-7 ◽  
Author(s):  
Huixue Jia ◽  
Liuyi Li ◽  
Weiguang Li ◽  
Tieying Hou ◽  
Hongqiu Ma ◽  
...  
Keyword(s):  
Length Of Stay ◽  
Bacterial Infections ◽  
Matched Control ◽  
Multidrug Resistant ◽  
Healthcare Associated Infections ◽  
E Coli ◽  
Significant Difference ◽  
Multidrug Resistant Pathogens ◽  
Healthcare Associated ◽  
Different Levels

Healthcare-associated infections (HAIs) not only bring additional medical cost to the patients but also prolong the length of stay (LOS). 2119 HAI case-patients and 2119 matched control-patients were identified in 68 hospitals in 14 primary sampling provinces of 7 major regions of China. The HAI caused an increase in stay of 10.4 days. The LOS due to HAI increased from 9.7 to 10.9 days in different levels of hospitals. There was no statistically significant difference in the increased LOS between different hospital levels. The increased LOS due to HAI in different regions was 8.2 to 12.6 days. Comparing between regions, we found that the increased LOS due to HAI in South China is longer than other regions except the Northeast. The gastrointestinal infection (GI) caused the shortest extra LOS of 6.7 days while the BSI caused the longest extra LOS of 12.8 days. The increased LOS for GI was significantly shorter than that of other sites. Among 2119 case-patients, the non-multidrug-resistant pathogens were detected in 365 cases. The average increased LOS due to these bacterial infections was 12.2 days. E. coli infection caused significantly shorter LOS. The studied MDROs, namely, MRSA, VRE, ESBLs-E. coli, ESBLs-KP, CR-E. coli, CR-KP, CR-AB, and CR-PA were detected in 381 cases (18.0%). The average increased LOS due to these MDRO infections was 14 days. Comparing between different MDRO infections, we found that the increased LOS due to HAI caused by CR-PA (26.5 days) is longer than other MDRO infections (shorter than 19.8 days).

scholarly journals Effects of Therapeutic Ceftiofur Administration to Dairy Cattle on Escherichia coli Dynamics in the Intestinal Tract

2008 ◽  
Vol 74 (22) ◽  
pp. 6956-6962 ◽  
Author(s):  
Randall S. Singer ◽  
Sheila K. Patterson ◽  
Richard L. Wallace
Keyword(s):  
Escherichia Coli ◽  
Antibiotic Treatment ◽  
Antibiotic Use ◽  
Multidrug Resistant ◽  
Causal Link ◽  
Susceptible Population ◽  
E Coli ◽  
Genetic Groups ◽  
Susceptibility Profiles ◽  
Cessation Of Treatment

ABSTRACT The goal of this study was to follow ceftiofur-treated and untreated cattle in a normally functioning dairy to examine enteric Escherichia coli for changes in antibiotic resistance profiles and genetic diversity. Prior to treatment, all of the bacteria cultured from the cows were susceptible to ceftiofur. Ceftiofur-resistant E. coli was only isolated from treated cows during and immediately following the cessation of treatment, and the 12 bla CMY-2-positive isolates clustered into two genetic groups. E. coli bacterial counts dropped significantly in the treated animals (P < 0.027), reflecting a disappearance of the antibiotic-susceptible strains. The resistant bacterial population, however, did not increase in quantity within the treated cows; levels stayed low and were overtaken by a returning susceptible population. There was no difference in the genetic diversities of the E. coli between the treated and untreated cows prior to ceftiofur administration or after the susceptible population of E. coli returned in the treated cows. A cluster analysis of antibiotic susceptibility profiles resulted in six clusters, two of which were multidrug resistant and were comprised solely of isolates from the treated cows immediately following treatment. The antibiotic treatment provided a window to detect the presence of ceftiofur-resistant E. coli but did not appear to cause its emergence or result in its amplification. The finding of resistant isolates following antibiotic treatment is not sufficient to estimate the strength of selection pressure nor is it sufficient to demonstrate a causal link between antibiotic use and the emergence or amplification of resistance.

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 Drug Resistance of Pathogens Causing Nosocomial Infection in Orthopedics from 2012 to 2017: A 6-Year Retrospective Study

2020 ◽  
Author(s):  
Xiaowei Yang ◽  
Runsheng Guo ◽  
Banglin Xie ◽  
Qi Lai ◽  
Jiaxiang Xu ◽  
...  
Keyword(s):  
Drug Resistance ◽  
Retrospective Study ◽  
Antimicrobial Resistance ◽  
Bacterial Infections ◽  
Multidrug Resistant ◽  
Dynamic Monitoring ◽  
Resistant Bacteria ◽  
Clinical Microbiology Laboratory ◽  
Valuable Insight ◽  
E Coli

Abstract Background: Hospital-acquired infections (HAIs) are an emerging global problem that increases in-hospital mortality, length of stay, and cost. We performed a 6-year retrospective study to provide valuable insight into appropriate antibiotic use in HAI cases. We also aimed to understand how hospitals could reduce pathogen drug resistance in a population that overuses antibiotics.Methods: All data (2012–2017) were obtained from the Hospital Information Warehouse and Clinical Microbiology Laboratory.Results: We isolated 1392 pathogen strains from patients admitted to the orthopedics department during 2012–2017. Escherichia coli (14.7%, 204/1392), Enterobacter cloacae (13.9%, 193/1392), and Staphylococcus aureus (11.3%, 157/1392) were the most common pathogens causing nosocomial infections. The dominant Gram-negative bacterium was E. coli, with high resistance to ampicillin, levofloxacin, cotrimoxazole, gentamicin, and ciprofloxacin, in that order. E. coli was least resistant to amikacin, cefoperazone-sulbactam. The most dominant Gram-positive bacterium was S. aureus, highly resistant to penicillin and ampicillin, but not resistant to fluoroquinolones and cotrimoxazole. Analysis of risk factors related to multidrug-resistant bacteria showed that patients with open fractures were significantly more susceptible to methicillin-resistant S. aureus infections (p < 0.05). Additionally, extended-spectrum β-lactamase-producing E. coli infections occurred significantly more often in patients with degenerative diseases (p < 0.05). Elderly patients tended to be more susceptible to multidrug-resistant bacterial infections, but this outcome was not statistically significant.Conclusions:Antimicrobial resistance is a serious problem in orthopedics. To effectively control antimicrobial resistance among pathogens, we advocate extensive and dynamic monitoring of MDR bacteria, coupled with careful use of antibiotics.

scholarly journals P-Doped Carbon Quantum Dots with Antibacterial Activity

Micromachines ◽  
2021 ◽  
Vol 12 (9) ◽  
pp. 1116
Author(s):  
Shuiqin Chai ◽  
Lijia Zhou ◽  
Shuchen Pei ◽  
Zhiyuan Zhu ◽  
Bin Chen
Keyword(s):  
Quantum Dots ◽  
Antibacterial Activity ◽  
Bacterial Infections ◽  
Fluorescence Emission ◽  
Carbon Quantum Dots ◽  
Microbial Pathogens ◽  
Electronic Interaction ◽  
Minimal Inhibitory Concentrations ◽  
E Coli ◽  
Zeta Potential Analysis

It is a major challenge to effectively inhibit microbial pathogens in the treatment of infectious diseases. Research on the application of nanomaterials as antibacterial agents has evidenced their great potential for the remedy of infectious disease. Among these nanomaterials, carbon quantum dots (CQDs) have attracted much attention owing to their unique optical properties and high biosafety. In this work, P-doped CQDs were prepared by simple hydrothermal treatment of m-aminophenol and phosphoric acid with fluorescence emission at 501 nm when excited at 429 nm. The P-doped CQDs showed effective antibacterial activity against Escherichia coli (E. coli) and Staphylococcus aureus (S. aureus). The minimal inhibitory concentrations (MICs) of P-doped CQD were 1.23 mg/mL for E. coli and 1.44 mg/mL for S. aureus. Furthermore, the morphologies of E. coli cells were damaged and S. aureus became irregular when treated with the P-doped CQDs. The results of zeta potential analysis demonstrated that the P-doped CQDs inhibit antibacterial activity and destroy the structure of bacteria by electronic interaction. In combination, the results of this study indicate that the as-prepared P-doped CQDs can be a promising candidate for the treatment of bacterial infections.

scholarly journals Antimicrobial Resistance, Serologic and Molecular Characterization of E. coli Isolated from Calves with Severe or Fatal Enteritis in Bavaria, Germany

Antibiotics ◽  
2021 ◽  
Vol 11 (1) ◽  
pp. 23
Author(s):  
Andrea Feuerstein ◽  
Nelly Scuda ◽  
Corinna Klose ◽  
Angelika Hoffmann ◽  
Alexander Melchner ◽  
...  
Keyword(s):  
Antimicrobial Resistance ◽  
Virulence Factors ◽  
Bacterial Infections ◽  
Multidrug Resistant ◽  
Enterotoxigenic Escherichia Coli ◽  
Economic Losses ◽  
Drug Resistant ◽  
E Coli ◽  
Extensively Drug Resistant ◽  
Amoxicillin Clavulanate

Worldwide, enterotoxigenic Escherichia coli (ETEC) cause neonatal diarrhea and high mortality rates in newborn calves, leading to great economic losses. In Bavaria, Germany, no recent facts are available regarding the prevalence of virulence factors or antimicrobial resistance of ETEC in calves. Antimicrobial susceptibility of 8713 E. coli isolates obtained from 7358 samples of diseased or deceased diarrheic calves were investigated between 2015 to 2019. Considerably high rates of 84.2% multidrug-resistant and 15.8% extensively drug-resistant isolates were detected. The resistance situation of the first, second and third line antimicrobials for the treatment, here amoxicillin-clavulanate, enrofloxacin and trimethoprim-sulfamethoxazole, is currently acceptable with mean non-susceptibility rates of 28.1%, 37.9% and 50.0% over the investigated 5-year period. Furthermore, the ETEC serotypes O101:K28, O9:K35, O101:K30, O101:K32, O78:K80, O139:K82, O8:K87, O141:K85 and O147:K89, as well as the virulence factors F17, F41, F5, ST-I and stx1 were identified in a subset of samples collected in 2019 and 2020. The substantially high rates of multi- and extensively drug-resistant isolates underline the necessity of continuous monitoring regarding antimicrobial resistance to provide reliable prognoses and adjust recommendations for the treatment of bacterial infections in animals.

scholarly journals Manual Reading of Sensititre™ Broth Microdilution System Panels Improves Accuracy of Susceptibility Reporting for Polymyxin Antibiotics

2021 ◽  
Author(s):  
Michelle M. Bellerose ◽  
Andrew E. Clark ◽  
Jung-Ho Youn ◽  
Rebecca A. Weingarten ◽  
Chelsea M. Crooks ◽  
...  
Keyword(s):  
Bacterial Infections ◽  
Microbial Growth ◽  
Susceptibility Testing ◽  
Polymyxin B ◽  
Multidrug Resistant ◽  
Error Rates ◽  
Broth Microdilution ◽  
Minimal Inhibitory Concentrations ◽  
Manual Inspection ◽  
Agar Dilution

Accurate and reproducible antimicrobial susceptibility testing (AST) of polymyxin antibiotics is critical, as these drugs are last-line therapeutic options for the treatment of multidrug-resistant Gram-negative bacterial infections. However, polymyxin AST in the routine laboratory remains challenging. In this study, we evaluated the performance of an automated broth microdilution (BMD) system (Sensititre™, ThermoFisher) compared to agar dilution (AD) for colistin and polymyxin B AST of 129 Enterobacterales, Pseudomonas aeruginosa and Acinetobacter baumannii complex clinical isolates. Minimal inhibitory concentrations (MICs) derived from the Sensititre™ instrument based on two operator comparisons demonstrated overall categorical agreement (CA) of 86% and 89% compared to AD for colistin and 89% and 92% compared to AD for polymyxin B. However, error rates were higher than recommended by CLSI. Manual inspection of microdilution wells revealed microbial growth and skip wells which were erroneously interpreted by the Aris™2X instrument. Using manually interpreted BMD MICs read by two operators increased the overall categorical agreements to 88% and 95% compared to AD for colistin and 92% and 96% compared to AD for polymyxin B. Laboratories choosing to use the Sensititre™ platform for polymyxin AST should consider manual evaluation of wells as part of their algorithm.

Sign in / Sign up

Export Citation Format

Share Document