Genetic characterization of high-level gentamicin-resistant strains of Enterococcus faecalis in Iran

Abstract

The prevalence of resistance to high levels of gentamicin among 182 isolates of Enterococcus faecalis from 2 Iranian hospitals was 42%. Gentamicin resistance was associated with conjugative plasmids (>70 kb) in most strains. Fingerprinting using EcoRI and HindIII showed genetic variation among these plasmids and gave evidence of nosocomial outbreaks and persistence of infection in different wards of the study hospitals, as well as transfer of plasmids between genetically diverse isolates. Using EcoRI, hospital-based specific plasmid fingerprints were detected for the isolates that had previously proved to be unrelated by multilocus enzyme electrophoresis, suggesting the persistence of related plasmids at each hospital, though minor changes in these related plasmids could be detected with HindIII.

Aminoglycosides: Mechanisms of Action and Resistance

“…The rapid dissemination of aminoglycoside resistance among pathogenic organisms has been largely attributed to conjugation of plasmids and non-replicative transposons among bacteria (119,120,123,124). A clinical example of the ongoing importance of conjugative plasmid transfer on resistance to aminoglycosides is the shocking case of untreatable and fatal neonatal septicemia mediated by Klebsiella pneumonia EK105, which carries a mobile plasmid encoding resistance to amikacin, ampicillin chloramphenicol, kanamycin, streptomycin, tobramycin, netilmicin, oxacillin, gentamicin, and mezlocillin (125).…”

Prevalence of vancomycin-resistant Enterococcus in Iran: a systematic review and meta-analysis

“…According to the data, a year later VRE was documented in US hospitals and emerged as one of the crucial hospital-acquired infectious agents [4]. In 2004, VRE strains were initially reported in Iran; and presently pertain to be a highly relevant nosocomial pathogen [5,6]. It is quite significant to mention that VRE has been identified as a global public health dilemma, as the therapeutic options for the treatment are utterly limited [3].…”