We investigated the prevalence and characteristics of Escherichia coli sequence type 131 (ST131) and its subclones among 268 E. coli isolates. The isolates were collected from 21 Korean hospitals without use of selection criteria and were screened for ST131 status by PCR. ST131 isolates were characterized for extended-spectrum β-lactamase variants, fluoroquinolone resistance genes, plasmid addiction systems, and replicon types. The collection's 57 identified ST131 isolates (21% of 268) were distributed disproportionately by clonal subset, as follows: 21 (37%) H30Rx, 27 (47%) H30 non-Rx, and 8 (14%) non- H30. Most (93%) ST131 isolates were ciprofloxacin resistant, and all H30 isolates had the same 5 nonsynonymous mutations in gyrA, parC, and parE. Twenty (95%) of H30Rx isolates harbored CTX-M-15, whereas only 14 (52%) of H30 non-Rx isolates harbored CTX-M-14 or CTX-M-27. Most (97%) ST131 isolates harbored IncF plasmids, but vagCD was confined exclusively to H30Rx. Our findings suggest that the distinctive characteristics of H30Rx isolates could have contributed to this subclone's recent epidemiologic success.
|Original language||English (US)|
|Number of pages||5|
|Journal||Diagnostic Microbiology and Infectious Disease|
|State||Published - Feb 1 2016|
Bibliographical noteFunding Information:
The authors thank all the contributing laboratories that provided isolates for this study. This work was supported by grants from St. Vincent Hospital in 2011 and from Samkwang Medical Laboratories in 2013 (SY Kim). This material is also based in part upon work supported by Office of Research and Development, Medical Research Service, Department of Veterans Affairs , grant no. 1 I01 CX000192 01 (JRJ).
- Escherichia coli