No abstract

The aim of this study was to identify risk factors for extended-spectrum β-lactamase (ESBL)-producing Escherichia coli (E coli) bloodstream infection (BSI) among carriers hospitalized between March 2011 and June 2016 at the ICU of the West China Hospital.The cases were patients with at least 1 episode of ESBL-producing E coli BSI within 1 week after a positive rectal swab. Controls were selected randomly 1:2 among ESBL-producing E coli rectal carriers who did not develop BSI.Among 19,429 ICU patients, 9015 (46.4%) had a positive rectal swab for ESBL-producing E coli. Of them, 42 (0.5%) were diagnosed with ESBL-producing E coli BSI. The in-hospital mortality was higher for the BSI patients compared with controls (19.1% vs. 6.0%, P = .031). In the past 72 hours, patients in case group were more likely to use penicillin (odds ratio [OR] = 12.076; 95% confidence interval [CI]: 1.397–104.251, P = .02), cephalosporin (OR = 6.900; 95% CI: 1.493–31.852, P = .01), and carbapenem (OR = 5.422; 95% CI: 1.228–23.907, P = .03) as compared to patients in control group. Also, when compared to patients in control group, patients in case group were likely to stay for a longer time in ICU before positive rectal swab test (OR = 1.041, 95% CI: 1.009–1.075, P = .01) and have higher maximum body temperature before positive rectal swab (OR = 8.014; 95% CI: 2.408–26.620, P = .001).Bacteremia owing to ESBL-producing E coli was associated with high antimicrobial exposure, hospital stay, and maximum body temperature.

X-100 and increased volume of test bacteria in the carbapenem inactivation method enhanced the detection of carbapenemase-producing Acinetobacter baumannii complex isolates.