Molecular Analysis of Antimicrobial Resistance Mechanisms in Neisseria gonorrhoeae Isolates from Ontario, Canada
| Autor: | Jingyuan Tan, Anuradha Rebbapragada, Donald E. Low, Stephen Lo, Lynn Towns, Nathalie Tijet, David J. Farrell, Vanessa Allen, Roberto G. Melano, Stephen Perusini |
|---|---|
| Rok vydání: | 2011 |
| Předmět: |
DNA
Bacterial Spectinomycin Tetracycline medicine.drug_class Molecular Sequence Data Microbial Sensitivity Tests Drug resistance Biology medicine.disease_cause Polymerase Chain Reaction Microbiology Gonorrhea Antibiotic resistance Bacterial Proteins Cefixime Mechanisms of Resistance Drug Resistance Bacterial medicine Humans Penicillin-Binding Proteins Pharmacology (medical) Amino Acid Sequence Ontario Pharmacology Ceftriaxone Sequence Analysis DNA biochemical phenomena metabolism and nutrition Quinolone Neisseria gonorrhoeae Anti-Bacterial Agents Cephalosporins Multiple drug resistance Penicillin Infectious Diseases medicine.drug |
| Zdroj: | Antimicrobial Agents and Chemotherapy. 55:703-712 |
| ISSN: | 1098-6596 0066-4804 |
| Popis: | Surveillance of gonococcal antimicrobial resistance and the molecular characterization of the mechanisms underlying these resistance phenotypes are essential in order to establish correct empirical therapies, as well as to describe the emergence of new mechanisms in local bacterial populations. To address these goals, 149 isolates were collected over a 1-month period (October-November 2008) at the Ontario Public Health Laboratory, Toronto, Canada, and susceptibility profiles (8 antibiotics) were examined. Mutations in previously identified targets or the presence of some enzymes related to resistance (r), nonsusceptibility (ns) (resistant plus intermediate categories), or reduced susceptibility (rs) to the antibiotics tested were also studied. A significant proportion of nonsusceptibility to penicillin (PEN) (89.2%), tetracycline (TET) (72.3%), ciprofloxacin (CIP) (29%), and macrolides (erythromycin [ERY] and azithromycin; 22.3%) was found in these strains. Multidrug resistance was observed in 18.8% of the collection. Although all the strains were susceptible to spectinomycin and extended-spectrum cephalosporins (ESC) (ceftriaxone and cefixime), 9.4% of them displayed reduced susceptibility to extended-spectrum cephalosporins. PBP 2 mosaic structures were found in all of these ESC rs isolates. Alterations in the mtrR promoter, MtrR repressor (TET r , PEN ns , ESC rs , and ERY ns ), porin PIB (TET r and PEN ns ), and ribosomal protein S10 (TET r ) and double mutations in gyrA and parC quinolone resistance-determining regions (QRDRs) (CIP r ) were associated with and presumably responsible for the resistance phenotypes observed. This is the first description of ESC rs in Canada. The detection of this phenotype indicates a change in the epidemiology of this resistance and highlights the importance of continued surveillance to preserve the last antimicrobial options available. |
| Databáze: | OpenAIRE |
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