Background: Extended-spectrum β-lactamases (ESBLs) production is the major
resistance mechanism to β-lactam antibiotics in Enterobacteriaceae. Moreover, the
emergence of quinolone resistance in ESBLs-producing isolates had become a global
threat for treatment of infections caused by these bacteria. Objectives: We investigated
the association between ESBLs production and quinolone resistance in Klebsiella
pneumoniae isolates. Methodology: A total of 148 isolates of K. pneumoniae collected
from Sohag University Hospital over the period of 10 months between June 2014 and
April 2015. Identification of Klebsiella pneumoniae was performed with the Vitek 2
system (bioMerieux, France). Screening for extended spectrum beta lactamases (ESBLs)
production was done with the Vitek 2 system (bioMérieux, France) and confirmed using
the combined disk diffusion test (CDDT) .The ESBL’s genotype was then analyzed by
multiplex PCR of blaTEM, blaSHV and blaCTX-M genes. Also multiplex PCR was used for
detection of quinolone resistance determinant genes qnrA, qnrB and qnrS among ESBLsproducing
K. pneumonia isolates. Results: In our study we found that among the 148 K.
pneumoniae isolates; 121 (81.7%) were ESBLs producers according to CDDT results,
bla TEM was found in 44% of them, while blaCTX-M found in 6%, blaTEM and blaCTX-M
together found in 39% of the isolates, but in 7% blaTEM, blaSHV were found together, the
three genes blaTEM, blaSHV and blaCTX-M were found in 4% but none of the isolates carried
blaSHV gene alone or with blaCTX-M. 113(93%) of the 121 ESBLs producing isolates were
found to carry one or more of quinolone resistance (QNR) genes qnrA, qnrB, qnrS. The
three genes together were found in (53.9%) of the isolates, while qnrS was found in
(29.1%), qnrA in (11%) of the isolates and (6%) carried both qnr B and S. Conclusions:
Our results showed coexistence of ESBLs production and quinolone resistance in the
majority of the K. pneumoniae isolates suggesting that more care should be taken for the
choice of antibiotic therapy beside strict application of infection control policies to
prevent dissemination of the multidrug resistant strains.