Emergence of new variants of ST131 clonal group among extraintestinal pathogenic Escherichia coli producing extended-spectrum β-lactamases

Four Main Virotypes among Extended-Spectrum-β-Lactamase-Producing Isolates of Escherichia coli O25b:H4-B2-ST131: Bacterial, Epidemiological, and Clinical Characteristics

“…This contrasts with the 9% prevalence of ST131 among the 92 analyzed ESBLEC isolates from a similar study from 2004 done in 11 Spanish hospitals (7 of which were included in the present study) (8). More recent studies found even higher prevalences of O25b-ST131 among ESBLECs in various Spanish cities, including Lugo in 2008 (23%) (5) and in 2012 (61%) (27), Barcelona (32% in 2008) (28), Seville (13% in 2010) (29), and Madrid (21% in 2008) (30). Other countries have also had high reported prevalences of ST131 among the ESBLEC strains, including Denmark (38%) (31), Japan (41%) (32), the United States (47%) (33), and Canada (78%) (34).…”

Characteristics of Extended-Spectrum β-Lactamases-Producing <i>Escherichia coli</i> in Fecal Samples of Inpatients of Beijing Tongren Hospital

“…Nonetheless, hospitalization 2 years before, the use of antibiotics within 3 months, and the use of glucocorticoids or immunosuppressive drugs were found to be obviously associated with the carriage of ESBL-producing E. coli. Several epidemiological studies have shown that E. coli ST131 may be a major cause of urinary-tract and bloodstream infections within the community as well as in hospitals or long-term care facilities in Europe, Asia, Africa, North America, and Australia (16)(17)(18)(19)(20)(21).…”

Rapid and Specific Detection, Molecular Epidemiology, and Experimental Virulence of the O16 Subgroup within Escherichia coli Sequence Type 131

“…We report here the first broad survey for this clade among unselected clinical isolates, as previous studies of this clade focused on ESBL-producing isolates from a single region (10)(11)(12), diverse convenience sample isolates (14,31), or all-comer isolates from a single locale (8,9,32). Our findings document that at multiple centers across the United States and Europe, the clade consistently accounts for approximately 1 to 5% of the E. coli clinical isolates overall and is associated with resistance to ampicillin, gentamicin, and TMP-SMZ but, especially in comparison with H30 ST131 isolates, with susceptibility to fluoroquinolones and extended-spectrum cephalosporins.…”

“…Although ST131 classically exhibits serotype O25b:H4, multiple studies have documented a minor subset of ST131 isolates with serotype O16:H5 or O-type O16 (7)(8)(9)(10)(11)(12). This O16 subset within ST131 remains poorly characterized.…”

“…Additionally, compared with classic O25b ST131 clade members, the studied O16 ST131 clade members exhibited a relatively greater prevalence of CTX-M-14 over (ST131-associated) CTX-M-15, were less commonly fluoroquinolone resistant but more commonly trimethoprimsulfamethoxazole resistant, and escaped detection by a widely used PCR screening assay for ST131 that targets the O25b rfb (O lipopolysaccharide) allele and the housekeeping gene pabB (10,11). Two O16 ST131 clade members also have been reported among 47 ESBL-producing ST131 clinical isolates from Lugo, Spain (12), and one among 12 ESBL-producing ST131 fecal isolates from children attending day care centers in southeastern France (13).…”