Prevalence and Characterization of Multidrug-Resistant and Extended-Spectrum Beta-Lactamase-ProducingEscherichia colifrom Pediatric Wards of a Malaysian Hospital

Abstract

The emergence of Escherichia coli resistant to extended-spectrum cephalosporins (ESCs) is of concern as ESC is often used to treat infections by Gram-negative bacteria. One-hundred and ten E. coli strains isolated in 2009-2010 from children warded in a Malaysian tertiary hospital were analyzed for their antibiograms, carriage of extended-spectrum beta-lactamase (ESBL) and AmpC genes, possible inclusion of the beta-lactamase genes on an integron platform, and their genetic relatedness. All E. coli strains were sensitive to carbapenems. About 46% of strains were multidrug resistant (MDR; i.e., resistant to ≥3 antibiotic classes) and almost half (45%) were nonsusceptible to ESCs. Among the MDR strains, high resistance rates were observed for ampicillin (98%), tetracycline (75%), and trimethoprim/sulfamethoxazole (73%). Out of 110 strains, bla(TEM-1) (49.1%), bla(CTX-M) (11.8%), and bla(CMY-2) (6.4%) were detected. Twenty-one strains were ESBL producers. CTX-M-15 was the predominant CTX-M variant found and this is the first report of a CTX-M-27-producing E. coli strain from Malaysia. Majority (3.1%) of the strains harbored class 1 integron-encoded integrases with a predominance of aadA and dfr genes within the integron variable region. No gene cassette encoding ESBL genes was found and integrons were not significantly associated with ESBL or non-ESBL producers. Possible clonal expansion was observed for few CTX-M-15-positive strains but the O25-ST131 E. coli clone known to harbor CTX-M-15 was not detected while CMY-2-positive strains were genetically diverse.

Emergence of Extended Spectrum-β-Lactamase-Producing Escherichia coli O25b-ST131

“…Similar findings of increasing prevalence and endemic spread of ESBL-producing E. coli have been reported in other studies. 9,15,31 The infants infected with E. coli O25b-ST131 and non-O25b-ST131 in the current study show no significant differences in the incidence of upper or lower UTI, clinical presentation, laboratory and imaging findings, severity of infection (ie, bacteremia, pyelonephritis, lobar nephronia or renal abscess) and outcomes (eg, mortality rate and defervescence within 48 hours of initial antimicrobial treatment, complications and recurrence rate). Other studies have also found similar rates of sepsis, bacteremia and mortality among ST131 and non-ST131-infected adult patients.…”

“…[1][2][3][4] Many reports describe fecal carriage and infection of ESBLproducing E. coli in children. [5][6][7][8][9][10][11][12][13][14] In 2008, two research groups studying CTX-M-15 ESBL-producing E. coli described "sero-group O25b-sequence type 131 (O25b-ST131)" as occurring in multiple countries in three continents. 15 The E. coli clonal group O25b-ST131 has been shown to carry a broad range of virulence and resistance genes on transferable plasmids, and has been globally disseminated.…”

Multidrug-resistant ESBL-producing Enterobacteriaceae and associated risk factors in community infants in Lebanon

“…ESBL-PE strains were detected in 12% (6/50) of fecal samples collected from the inpatients of a Japanese pediatric hospital, and all the ESBLs belonged to the CTX-M-1 group [31]. The carriage rate of ESBLproducing E. coli strains isolated from children warded in a Malaysian tertiary hospital was 19.1% (21/110), and CTX-M-15 was the predominant type [32]. ESBLs were identified in 13.4% (18/143) of E. coli isolates from Libyan children's stools, and all isolates that produced ESBLs belonged to CTX-M type [33].…”

Antimicrobial Resistance in Asia: Current Epidemiology and Clinical Implications

“…The international dissemination of bla CTX-M ESBL genes and ST131 over the last decade has been described as a pandemic. CTX-M-producing E. coli and ST131 have emerged as a significant cause of both community-onset and hospital-acquired infections in Asian countries, including Korea [49], Taiwan [50], China [51], Hong Kong [52], Japan [53], Malaysia [54], and Thailand [55], and the incidence of serious infections due to CTX-M-producing E. coli likely will continue to increase. CTX-M-producing E. coli have been highly endemic worldwide.…”