Characterization of Integrons and qnr Genes in Proteeae from a Teaching Hospital in China

Chemotherapy. 2017;62(1):12-18. doi: 10.1159/000445426. Epub 2016 May 25.

Abstract

Background: Proteeae isolates displaying multidrug-resistance (MDR) are the second most common causes of hospital-associated infections. The aim of this study was to screen class 1-3 integrons and plasmid-mediated quinolone resistance (PMQR) genes in Proteeae isolates from the First Affiliated Hospital of the Wenzhou Medical University.

Materials and methods: 176 Proteeae isolates were collected from clinical specimens of inpatients between January 2011 and December 2013. Susceptibility testing was determined by the agar dilution method. Class 1-3 integrons and PMQR genes were amplified by polymerase chain reaction, and the variable regions of integrons were determined by restriction fragment length polymorphisms.

Results: 68.2% Proteeae isolates exhibited MDR phenotypes: 46.6 and 10.8% Proteeae isolates were positive for intI1 and intI2, respectively. The resistance rate of integron-positive isolates to aminoglycosides, fluoroquinolones, and trimethoprim/sulfamethoxazole was significantly higher than integron-negative isolates. Sequence analysis revealed that dfrA1-sat2-aadA1, dfrA1-catB2-sat2-aadA1, and sat2-aadA1 were first detected in Morganella morganii strains isolated from China. PMQR was determined by qnrD in 40 strains (22.7%).

Conclusion: Our results indicate that class 1 and 2 integrons are common among Proteeae isolates. Meanwhile, qnrD are highly prevalent in Proteeae isolated from our hospital.

MeSH terms

  • Anti-Bacterial Agents / pharmacology
  • Bacterial Proteins / genetics*
  • Blotting, Southern
  • China
  • DNA, Bacterial / genetics
  • DNA, Bacterial / metabolism
  • Drug Resistance, Multiple, Bacterial / drug effects
  • Gram-Negative Bacteria / drug effects
  • Gram-Negative Bacteria / genetics*
  • Gram-Negative Bacteria / isolation & purification
  • Hospitals, Teaching
  • Humans
  • Integrons / genetics*
  • Microbial Sensitivity Tests
  • Polymerase Chain Reaction

Substances

  • Anti-Bacterial Agents
  • Bacterial Proteins
  • DNA, Bacterial