Objective. Plasmid-mediated quinolone resistance (PMQR) plays an important role in the development of clinical resistance to quinolone. The aim of this study was to investigate PMQR determinants among extended-spectrumβ-lactamases- (ESBL-) producingKlebsiella pneumoniaerecovered from patients with nosocomial urinary tract infection (UTI).Methods. A total of 247 ESBL-producingK. pneumoniaeisolates were collected from 750 patients with UTI. ESBL production was confirmed by double disc synergy test and combined disc diffusion test. The prevalence of PMQR determinants among ESBL-producingK. pneumoniaewas assessed using PCR method.Results. The rates of resistance to antimicrobial agents in present study varied from 14.2% to 98.8%. In comparison with other PMQR genotypes, the frequency ofaac(6′)-Ib(68.8%) was strikingly high. Of the 247 isolates tested,qnrA, qnrB, qnrS,andqepAgenes were present in 3.6%, 1.6%, 1.2, and 2%, respectively.oqxAandoqxBwere detected in 56.7% and 54.6% of isolates. The predominant coexisting ESBL and PMQR profile among our isolates includedblaCTX-Mandaac(6′)-Ib, oqxA, oqxB(28.3%) andblaTEM,blaSHVandaac(6′)-Ib, oqxA,andoqxB(19.4%) profile. Conclusion. Given the linkage observed between resistance to quinolones and beta lactam antibiotics, therapeutic protocol with fluoroquinolones and beta lactam antibiotics should be seriously revised in Tehran hospitals.
Relevance of in vitro antibacterial activities and pharmacokinetic properties of antipseudomonal .BETA.-lactam antibiotics to their therapeutic effects on urinary tract infection caused by Pseudomonas aeruginosa P 9 in mice.
