Prospective Cohort Study of the Relative Abundance of Extended-Spectrum-Beta-Lactamase-Producing Escherichia coli in the Gut of Patients Admitted to Hospitals

Abstract

A total of 458 patients were prospectively included at hospital admission and screened for extended-spectrum-beta-lactamaseproducing (ESBL) Escherichia coli carriage in 2007 and in 2010 to 2012. A 4-fold increase in ESBL carriage (3% to 12%), a 5-fold increase in numbers of community patients among ESBL carriers, and a higher number of multiple ESBL strains was found in the 2010 to 2012 period. ESBL E. coli represented the dominant E. coli strain (relative abundance, >50%) in 10/32 (31%) of ESBL carriers. This represents a major threat in terms of infectious risk and dissemination.T he epidemiology of Escherichia coli infections has recently been profoundly modified with the global emergence of strains resistant to third-generation cephalosporins (3GC), specifically, strains producing extended-spectrum ␤-lactamases (ESBL), in both hospitals and the community (1). CTX-M-type ESBLs, which have spread in a polyclonal manner on all continents, constitute a major public health concern worldwide (1).Gut colonization is the first step toward infections by E. coli (2). Recently, it has been shown that a high relative abundance (RA) of ESBL E. coli in the feces increases the risk of urinary tract infection (UTI) by ESBL E. coli (3). Additionally, a high ESBL E. coli RA has been associated with longer fecal carriage time, increasing the numbers of excreted E. coli in the environment and the potential risk of dissemination of these resistant strains (4). However, most studies focusing on ESBL fecal carriage have described the presence or absence of ESBL E. coli in the gut but have lacked quantitative data. Moreover, whether the ESBL populations are dominant was not specified. Here, we characterized and determined the prevalence, bacterial load, and diversity of ESBL E. coli in the gut of patients at hospital admission at two different time periods and determined factors associated with high relative abundance of ESBL carriage.We used samples collected in two previous prospective clinical trials (5, 6) (https://clinicaltrials.gov/ct2/show/NCT00520715 and https://clinicaltrials.gov/ct2/show/NCT01209247). In both works, clinical data (age, sex, Charlson comorbidity index, hospitalization ward, history of immunosuppression, previous hospitalization in the last 12 months, previous antibiotic exposure in the last 3 months, and antibiotic class) as well as a rectal swab had been collected from patients at admission in the same two tertiarycare hospitals from the Paris region in France (5, 6). The first collection period (P1) was between May and November 2007, and the second period (P2) was between October 2010 and July 2012. Both studies were approved by the local institutional review board (IRB 00008522), and patients gave informed consent (5, 6). Rectal swabs were discharged in 1 ml of brain heart infusion (BHI) broth with glycerol and stored at Ϫ80°C in duplicates (5, 6). After thawing, 50 l was plated on Drigalski agar plates (Pasteur Diagnostics, Paris, France), one containing no antibiotics and one containing 1 g/ml cefotax...

Dissemination of carbapenemase-producing Enterobacterales in the community of Rawalpindi, Pakistan

“…The mean relative abundance of CRE (CRE-RA) was similar to that found in other studies in Europe for community ESBL-producing E. coli [68,69] highlighting that in patients with no recent exposure to antibiotics, multidrug-resistant Enterobacterales remain subdominant. Surprisingly though, the mean CRE-RA of hospital-acquired CRE was not higher.…”

Aerobic bacteria as Escherichia coli can survive in ESwabTM medium after a 3 month-freezing at −80°C but not after multiple thawing

“…The other MDRO belong mainly to the ESKAPE group ( Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa , and Enterobacter species) (5). Likewise, those species are also opportunistic pathogens and quantitative studies of the prevalence, bacterial load and diversity of these species as well as E. coli in their natural environment, which is the digestive gut, are essential (3, 6, 7).…”

“…So far quantitative studies of E. coli in the feces have been performed using fresh feces or rectal swabs rapidly seeded or placed in Brain Heart infusion (BHI) with glycerol and placed at −80°C (3, 6, 7). In prospective studies, these procedures are time consuming and can not be applied in numerous labs.…”

Screening for antimicrobial-resistant Gram-negative bacteria in hospitalised patients, and risk of progression from colonisation to infection: Systematic review

“…Out of 86 studies included in SR1 , 75 were included in qualitative analysis 13,14,[16][17][18][19][20][21][22][23][24][25]27,28,30,[32][33][34][35][36][38][39][40][41][74][75][76][77][78][79][80][81][82][83]85,86,90,91 as two reported on repeated screening procedures (excluding two studies 34,63 ) and nine reported on screening activities in outbreak situations 15,29,31,37,42,84,[87][88][89] . Among included studies, 24 concerned routine care screenings 41,…”