Detection of aac(6')-Ib-cr in KPC-producing Klebsiella pneumoniae isolates from Tel Aviv, Israel.
OBJECTIVE
We aimed to evaluate the occurrence and characteristics of plasmid-mediated quinolone resistance (PMQR) genes in KPC-producing (KPC-P) Klebsiella pneumoniae (Kpn) isolates in Tel Aviv Medical Center, Israel.


METHODS
Forty-seven KPC-P Kpn isolates were studied. Antibiotic susceptibilities were determined by Vitek 2, Etest or agar dilution. Beta-lactamases and PMQR determinants were detected by PCR. For plasmid characterization, transformation, transconjugation, restriction mapping and Southern blot analysis were performed.


RESULTS
Six out of 47 (13%) KPC-P isolates carried aac(6')-Ib-cr. Acquisition of aac(6')-Ib-cr-encoding plasmids increased the MIC of ciprofloxacin by 2-fold. In five of six KPC-P isolates, aac(6')-Ib-cr and bla(KPC-2) were encoded on the same plasmid.


CONCLUSIONS
The most prevalent PMQR gene in the studied KPC-P K. pneumoniae isolates is aac(6')-Ib-cr. The co-existence of PMQR genes with KPC on the same plasmid poses a serious epidemiological, clinical and public-health threat.
Chmelnitsky
Inna
I
Division of Epidemiology, Tel Aviv Medical Center, Tel Aviv, Israel. innach@tasmc.health.gov.il
Hermesh
Orit
O
Navon-Venezia
Shiri
S
Strahilevitz
Jacob
J
Carmeli
Yehuda
Y
D000123:Acetyltransferases / Q000096:biosynthesis* / Q000235:genetics; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001426:Bacterial Proteins / Q000096:biosynthesis* / Q000235:genetics; D015139:Blotting, Southern; D003227:Conjugation, Genetic; D024881:Drug Resistance, Bacterial; D005798:Genes, Bacterial; D006801:Humans; D007557:Israel; D007710:Klebsiella Infections / Q000382:microbiology*; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000235:genetics / Q000302:isolation & purification; D008826:Microbial Sensitivity Tests / Q000379:methods; D010957:Plasmids / Q000032:analysis; D016133:Polymerase Chain Reaction / Q000379:methods; D015363:Quinolones / Q000494:pharmacology*; D015183:Restriction Mapping; D014170:Transformation, Genetic; D001618:beta-Lactamases / Q000096:biosynthesis* / Q000235:genetics
D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D015363:Quinolones; D000123:Acetyltransferases; C019681:aminoglycoside acetyltransferase; D001618:beta-Lactamases; C063912:carbapenemase