Background
The aim of this study was to characterize class 1,2 and 3 integrons in clinical MDR
Klebsiella pneumoniae
isolates in Kashan, Iran.
Methods
One hundred-eighty one
Klebsiella pneumoniae
were recovered from clinical specimens during November 2013 to October 2014. Antimicrobial susceptibility patterns were determined by disk diffusion method according to the Clinical and Laboratory Standards Institute (CLSI) guidelines for detection of MDR strains. Of the 181
Klebsiella pneumoniae,
146 (80.7%) of isolates were isolated from nosocomial infected patients and 150 (82.9%) identified as MDR isolates. The PCR amplification was used to show presence of class 1, 2 and 3 integrons among MDR strains. The PCR method and sequencing were used for evaluation of cassette content of integrons.
Results
Of the MDR
K. pneumoniae
isolates, 150 (100%) and 55 (36.7%) carried
intI1
and
intI2
genes, respectively. None of the MDR
Klebsiella pneumoniae
isolates carried class 3 integrons. Amplification of conserved segment (CS) of class 1 and class 2 integrons revealed 10 different arrays including: No. cassette;
dfrA5
,
dfrA30
;
aadA2
;
aadA2
,
dfrA12
;
dfrA17
,
aadA5
,
aadA4
;
dfrA5
,
dfrA30
,
aadA2
;
dfrA5
,
dfrA30
,
aadA2
,
dfrA12, dfrA5
,
dfrA30
,
dfrA17
,
aadA5
,
aadA4
;
aadA2
,
aadA2
,
dfrA12
;
dfrA5
,
dfrA30
,
aadA2
,
aadA2
,
dfrA12
and 4 arrays including: No. cassette;
aadA1
;
dfrA1-sat1
;
aadA1
,
dfrA1-sat1
, respectively.
Conclusions
The finding of present study revealed a high prevalence of integrons especially class 1 among MDR
K. pneumoniae
isolates from nosocomial infections in Kashan, which led to rapid extension of MDR strains.