الفهرس 
Klebsiella pneumoniae
Germany imipenemase metallo-enzymesOnly 14 pages are availabe for public view
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Abstract
Klebsiella pneumoniae (K. pneumoniae) is an important multidrugresistant
(MDR) Gram negative pathogen that affects human and causes
serious opportunistic infections. The significant spread of carbapenem
resistance among K. pneumoniae isolates represents a serious threat to both
hospitals and community. In this study, out of 1005 different clinical
samples, obtained from four hospitals in Kafrelsheikh city; Egypt, 230 K.
pneumoniae isolates (22.8%) were recovered during the period from July
2015 to April 2016. All recovered K. pneumoniae isolates were identified
using conventional standard biochemical tests and confirmed by automated
Vitek2® compact system. Antimicrobial susceptibility test was performed by
Kirby-Bauer disk diffusion method and confirmed also by automated
Vitek2® compact system. The results showed high incidence (21.7%) of
carbapenem resistance where among the tested K. pneumoniae, 50 isolates
were found to be imipenem and meropenem non-susceptible. For other tested
antimicrobials, K. pneumoniae isolates recorded also high incidence of
resistance that ranged from 98.3% for ampicillin to 60% for tobramycin.
The detected carbapenem resistant K. pneumoniae isolates were
selected for further study. It was observed that those isolates were resistant to
all tested β-lactams and tobramycin. On the other hand, tigecycline and
colistin represented the most active agents. As a result, the tested carbapenem
resistant K. pneumoniae isolates showed different resistance profiles where
44 isolates were MDR, 6 isolates were XDR but none of the tested isolates
was PDR.
Carbapenemases production among all carbapenem resistant K.
pneumoniae isolates was examined phenotypically using Modified Hodge
Abstract
III
test (MHT) and combined disk synergy test (CDST). The results showed that
90% of isolates were carbapenemases producers while 66% were found to be
metallo beta lactamases (MBLs) producers.
Carbapenem resistant K. pneumoniae isolates were further subjected to
molecular analysis using polymerase chain reaction (PCR) technique for
screening and detection of carbapenem resistance-associated genes (including
blaKPC, blaGES, blaNDM-1, blaVIM, blaIMP and blaOXA-48 genes). The results
revealed that blaNDM-1 and blaOXA-48 were the only detected genes (with
incidence of 70% and 52% respectively) among tested carbapenem resistant
K. pneumoniae isolates. Up to 37 isolates harbored at least one of these
genes; among them 24 isolates co-harbored both detected genes while other
11 isolates harbored only blaNDM-1 and the remaining 2 isolates harbored only
blaOXA-48. For further molecular analysis, DNA sequencing of the detected
blaNDM-1 and blaOXA-48 genes was carried out for nine isolates representing
different resistance patterns. The sequences of amplified blaNDM-1 and
blaOXA48 genes were submitted to the Gene Bank databases and assigned the
following accession numbers MG594615 and MG594616, respectively. In
conclusion, our study reported high incidence of MDR and XDR profiles
with emergence of blaNDM-1 and blaOXA-48 co-existence among carbapenem
resistant K. pneumoniae isolates from Kafrelsheikh city, Egypt. Hence, our
findings highly recommended the necessity for applying strict infection
control strategies against the dissemination of such serious carbapenem
resistant K. pneumoniae pathogens otherwise it would be seriously difficult
to control and limit the infections caused by such pathogens.