Background: Quinolone resistance (QR) is one component of the MDR emerging in Escherichia coli and is of particular concern given the widespread use of fluoroquinolones.
Objectives: To characterize the QR phenotypes and genotypes in E. coli responsible for bloodstream infections and to propose molecular determinants that could be targeted to predict ciprofloxacin resistance.
Methods: E. coli isolates from blood cultures in three French hospitals were studied for quinolone MICs and characterization of genotypic QR determinants (QRg).
Results: Among 507 isolates tested for MICs, 148 (29.2%) were resistant to quinolones based on EUCAST breakpoints and 143 (28.2%) harboured at least one QRg. QRg were mainly mutations in the QRDR (138 isolates, 27.2%), with 55.8% of these isolates carrying at least three QRDR mutations. gyrA mutations predominated (92.8%) followed by parC (61.6%), parE (32.6%) and gyrB (1.4%) mutations. Only 4.7% of the isolates harboured a plasmid-mediated quinolone resistance (PMQR) gene: aac(6')-Ib-cr (60.0%) or qnr (qnrS, qnrB) (32.0%). For the first time in France, we reported the qepA4 allele of the plasmid-encoded efflux pump QepA. Only five isolates carried PMQR without a QRDR mutation. The positive predictive value (PPV) for ciprofloxacin resistance was 100% for any QRg and 99.2% for gyrA mutations specifically.
Conclusions: QR observed in E. coli isolates involved in bloodstream infections is still mainly due to QRDR mutations, especially at codons GyrA83/87, which could be used as a molecular target to rapidly detect resistance.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1093/jac/dkaa189 | DOI Listing |
PLoS Biol
January 2025
Department of Biophysics, University of Michigan, Ann Arbor, Michigan, United States of America.
As failure rates for traditional antimicrobial therapies escalate, recent focus has shifted to evolution-based therapies to slow resistance. Collateral sensitivity-the increased susceptibility to one drug associated with evolved resistance to a different drug-offers a potentially exploitable evolutionary constraint, but the manner in which collateral effects emerge over time is not well understood. Here, we use laboratory evolution in the opportunistic pathogen Enterococcus faecalis to phenotypically characterize collateral profiles through evolutionary time.
View Article and Find Full Text PDFPathogens
December 2024
College of Public Health, Shanghai University of Medicine & Health Sciences, Shanghai 201318, China.
This study aimed to explore the interactions among genetic determinants influencing ciprofloxacin resistance in . Treatment with PAβN, an efflux pump inhibitor, resulted in a 4-32-fold reduction in the minimum inhibitory concentration (MIC) across all 18 ciprofloxacin-resistant isolates. Notably, isolates without point mutations reverted from resistance to sensitivity.
View Article and Find Full Text PDFInt J Mol Sci
December 2024
Institute of Chemical Biology and Fundamental Medicine SB RAS, Novosibirsk 630090, Russia.
Globally, widespread tuberculosis is one of the acute problems of healthcare. Drug-resistant forms of tuberculosis require a personalized approach to treatment. Currently, rapid methods for detecting drug resistance of (MTB) to some antituberculosis drugs are often used and involve optical, electrochemical, or PCR-based assays.
View Article and Find Full Text PDFMedicina (Kaunas)
December 2024
Department of Clinical and Chemical Pathology, Faculty of Medicine, Cairo University, Cairo 12613, Egypt.
A dangerous infection contracted in hospitals, ventilator-associated pneumonia is frequently caused by bacteria that are resistant to several drugs. It is one of the main reasons why patients in intensive care units become ill or die. This research aimed to determine the most effective empirical therapy of antibiotics for better ventilator-associated pneumonia control and to improve patient outcomes by using the minimal inhibitory concentration method and the Ameri-Ziaei double antibiotic synergism test and by observing the clinical responses to both single and combination therapies.
View Article and Find Full Text PDFEnviron Res
January 2025
Key Laboratory of Oasis Ecology of Education Ministry, College of Ecology and Environment, Xinjiang University, Urumqi 830017, P.R. China; Xinjiang Jinghe Observation and Research Station of Temperate Desert Ecosystem, Ministry of Education, Urumqi 830017, P.R. China.
Antibiotics and antibiotic resistance genes (ARGs) are severe refractory pollutants in water. However, the effect of an intermittent electrical stimulation on the removal of antibiotics and ARGs from saline wastewater remains unclear. An anaerobic-aerobic-coupled upflow bioelectrochemical reactors (AO-UBERs) was used to treat tetracycline (TC) and quinolone (QN) in saline wastewater.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!