Molecular epidemiology of clinical Pseudomonas aeruginosa isolates carrying IMP-1 metallo-beta-lactamase gene in a University Hospital in Turkey.
Pseudomonas aeruginosa isolates carrying IMP- or VIM-type metallo-beta-lactamase (MBL) have been increasingly reported in hospitals worldwide. One hundred P. aeruginosa clinical isolates from unrelated inpatients hospitalized at a Turkish university hospital were screened for the presence of bla(IMP) and bla(VIM) genes by polymerase chain reaction (PCR). One (1%) isolate was found to carry a VIM-type MBL gene, whereas nine (9%) carried an IMP-1 MBL gene carried on a cassette inserted into a class 1 integron. Only four of the IMP producers were detected as MBL producers according to E-test MBL. Minimum inhibitory concentrations (MICs) of imipenem for the IMP-1 and VIM-type MBL-producers were highly variable (MIC values, 8-128 mug/ml). Imipenem resistance was not plasmid-mediated according to the transformation assays. Piperacillin/tazobactam was the only effective drug in antimicrobial susceptibility testing. No aztreonam-resistant IMP and VIM producers were detected to produce an extended-spectrum beta-lactamase (ESBL). Three class 1 integrons of approximately 2,300 bp, 1,800 bp, and 1,500 bp in size were detected in each of the nine IMP-positive isolates. Sequencing revealed three novel gene cassette arrays, aac(3)-1c-cmlA5, bla(IMP-1)-aadA7-like, and aacA7-smr-2-orfD. Enterobacterial repetitive intergenic consensus PCR (ERIC-PCR) indicated that a clonal spread of IMP-1-producers had occurred in this hospital.
Ozgumus
Osman Birol
OB
Department of Biology, Rize Faculty of Arts & Sciences, Karadeniz Technical University, 53100 Rize, Turkey. microbsman@yahoo.com
Caylan
Rahmet
R
Tosun
Ilknur
I
Sandalli
Cemal
C
Aydin
Kemalettin
K
Koksal
Iftihar
I
D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000494:pharmacology*; D001398:Aztreonam / Q000494:pharmacology; D024901:Drug Resistance, Multiple, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial; D006785:Hospitals, University; D006801:Humans; D015378:Imipenem / Q000008:administration & dosage / Q000494:pharmacology; D032023:Integrons; D008826:Microbial Sensitivity Tests; D017720:Molecular Epidemiology; D008969:Molecular Sequence Data; D010397:Penicillanic Acid / Q000008:administration & dosage / Q000031:analogs & derivatives / Q000494:pharmacology; D010878:Piperacillin / Q000008:administration & dosage / Q000494:pharmacology; D000077725:Piperacillin, Tazobactam Drug Combination; D010957:Plasmids; D016133:Polymerase Chain Reaction; D011552:Pseudomonas Infections / Q000453:epidemiology / Q000382:microbiology*; D011550:Pseudomonas aeruginosa / Q000187:drug effects* / Q000235:genetics / Q000302:isolation & purification; D014421:Turkey / Q000453:epidemiology; D001618:beta-Lactamases / Q000235:genetics
D000900:Anti-Bacterial Agents; D000077725:Piperacillin, Tazobactam Drug Combination; D015378:Imipenem; D010397:Penicillanic Acid; C417264:VIM-1 metallo-beta-lactamase; C409201:beta-lactamase IMP-1; D001618:beta-Lactamases; D001398:Aztreonam; D010878:Piperacillin