Investigation of Plasmid-Mediated Quinolone Resistance in Pseudomonas aeruginosa Clinical Isolates

Abstract

Aims: To investigate plasmid-mediated quinolone resistance in clinical isolates of Pseudomonas aeruginosa with the polymerase chain reaction (PCR). The plasmid-mediated quinolone resistance genes have been identified in many bacteria within the Enterobactericeae family, they have not been detected in P. aeruginosa isolates. Subjects and Methods : Identification of the isolates and testing of antibiotic susceptibility was performed in Vitek2 Compact (Biomeriux, France) and Phoinex (BD, USA) automated systems. Screening for the qnrA, qnrB, qnrS, qnrC, aac (6′)-Ib-cr and qepA genes was carried out by PCR amplification and aac (6′)-Ib-cr DNA sequencing. Results: The qnr and the qepA genes were not detected in any of P. aeruginosa isolates. The aac (6′)-Ib gene was detected in six of the isolates and positive isolates for aac (6′)-Ib were sequenced for detection of the aac (6′)-Ib-cr variant but aac (6′)-Ib-cr was not detected in any isolates. Conclusions: Plasmid-mediated quinolone resistance genes have so far not been identified in P. aeruginosa isolates. However, qnrB have detected in P. florescens and P. putida isolates. This is the first study conducted on the qnrA, qnrB, qnrS and qnrC genes as well as the qepA and aac (6′)-Ib-cr genes in P. aeruginosa clinical isolates.