Characteristics of plasmid-mediated quinolone resistance genes in extended-spectrum cephalosporin-resistant isolates of Klebsiella pneumoniae and Escherichia coli in Korea

Mi-Ran Seo, Yoon Soo Park, Hyunjoo Pai
Chemotherapy 2010, 56 (1): 46-53

BACKGROUND: Quinolone resistance is frequently associated with extended-spectrum cephalosporin resistance in Enterobacteriaceae.

METHODS: The characteristics of plasmid-mediated quinolone resistance (PMQR) genes [qnr genes, aac(6')-Ib-cr and qepA] in clinical isolates of Klebsiella pneumoniae and Escherichia coli resistant to extended-spectrum cephalosporin were studied.

RESULTS: 5 and 4 of 95 E. coli isolates but 46 (86/187) and 6% (12/187) of K. pneumoniae had qnr and aac(6')-Ib-cr, respectively, and 8 K. pneumoniae contained both genes.qepA was not identified. qnrB, especially qnrB4, was the predominant qnr subtype in K. pneumoniae [94 (88 qnrB of 94 qnr) and 88% (77 qnrB4 of 88 qnrB), respectively], and presence of qnrB4 was closely related with DHA-1 beta-lactamase (99%). However, K. pneumoniae isolates with qnrB4 and bla(DHA-1) were clonally diverse. beta-Lactamases produced by PMQR-containing isolates were variable: CMY-1, CTX-M-14, CTX-M-15, DHA-1, OXA type, SHV-2a, and SHV-12.

CONCLUSION: PMQR genes are widely distributed among clinical isolates of K. pneumoniae, and qnrB4 associated with bla(DHA-1) was the most common PMQR gene in Korea.

Full Text Links

Find Full Text Links for this Article


You are not logged in. Sign Up or Log In to join the discussion.

Related Papers

Remove bar
Read by QxMD icon Read

Save your favorite articles in one place with a free QxMD account.


Search Tips

Use Boolean operators: AND/OR

diabetic AND foot
diabetes OR diabetic

Exclude a word using the 'minus' sign

Virchow -triad

Use Parentheses

water AND (cup OR glass)

Add an asterisk (*) at end of a word to include word stems

Neuro* will search for Neurology, Neuroscientist, Neurological, and so on

Use quotes to search for an exact phrase

"primary prevention of cancer"
(heart or cardiac or cardio*) AND arrest -"American Heart Association"