Epidemiology and characteristics of Escherichia coli sequence type 131 (ST131) from long-term care facility residents colonized intestinally with fluoroquinolone-resistant Escherichia coli

Abstract

The objective of this study was to evaluate molecular and epidemiologic factors associated with Escherichia coli sequence type 131 (ST131) among long-term care facility (LTCF) residents who acquired gastrointestinal tract colonization with fluoroquinolone-resistant E. coli (FQREC). Colonizing isolates from 37 residents who newly developed FQREC colonization at three LTCFs from 2006–2008 were evaluated. Twenty-nine (78%) of 37 total FQREC colonizing isolates were ST131. Most ST131 isolates had a distinctive combination of gyrA and parC replacement mutations. The ST131 and non-ST131 isolates differed significantly for the prevalence of many individual virulence factors but not for the proportion that qualified molecularly as extraintestinal pathogenic E. coli (ExPEC) or aggregate virulence factor scores. E. coli ST131 was highly prevalent among LTCF residents with FQREC colonization. Future studies should determine the risk factors for infection among ST131-colonized residents, and assess the potential for increased transmissibility of ST131 in the long-term care setting.

Clonal diversity, virulence genes content and subclone status of Escherichia coli sequence type 131: comparative analysis of E. coli ST131 and non-ST131 isolates from Iran

“…The proportions of fimH , fyuA , iutA , traT , and PAI genes were similar to those in previous reports [19, 20], although the proportions of hlyA / cnf1 and ompT/sat were different from those reported in previous Korean/Indian and U. S studies [20–22]. This result suggests that differences in virulence profiles among ST131 strains may depend on their geographical origin, whether the study was hospital/ “long-term care facility” or community based, and the source of isolates.…”

Intestinal colonization due to Escherichia coli ST131: risk factors and prevalence

“…In healthcare centers, Han et al could not identify relevant differences between 29 and 8 long-term care facility (LTCF) residents colonized with ST131 and non-ST131 fluoroquinolone-resistant E. coli . [ 11 ]; in another study in a LTCF, Burgess et al found that time of admission, being unable to sign consent, decubitus ulcer and fecal incontinence were risk factors for colonisation with ciprofloxacin-resistant ST131 E. coli [ 12 ]. Other studies only investigated ESBL-producing ST131 isolates [ 1 , 2 ].…”

Double-Serine Fluoroquinolone Resistance Mutations Advance Major International Clones and Lineages of Various Multi-Drug Resistant Bacteria

“…Moreover, non-ST131 E. coli strains were reported to be just as virulent as some ST131 isolates (Ciesielczuk et al, 2015 ). Though, Cha et al ( 2016 ) recently alleged that the ST131 clone was more virulent than others, Han et al ( 2017 ) showed that ST131 strains fail to excel in aggregate virulence. Furthermore, Dahbi et al ( 2014 ) reported that ST131 isolates show diverse virulence and low-virulence isolates are common among them.…”