title: Risk factors for colonization with extended-spectrum beta-lactamase-producing bacteria and intensive care unit admission.
abstract: Extended-spectrum beta-lactamase (ESBL)-producing bacteria are emerging pathogens. To analyze risk factors for colonization with ESBL-producing bacteria at intensive care unit (ICU) admission, we conducted a prospective study of a 3.5-year cohort of patients admitted to medical and surgical ICUs at the University of Maryland Medical Center. Over the study period, admission cultures were obtained from 5,209 patients. Of these, 117 were colonized with ESBL-producing Escherichia coli and Klebsiella spp., and 29 (25%) had a subsequent ESBL-positive clinical culture. Multivariable analysis showed the following to be statistically associated with ESBL colonization at admission: piperacillin-tazobactam (odds ratio [OR] 2.05, 95% confidence interval [CI] 1.36-3.10), vancomycin (OR 2.11, 95% CI 1.34-3.31), age > 60 years (OR 1.79, 95% CI 1.24-2.60), and chronic disease score (OR 1.15; 95% CI 1.04-1.27). Coexisting conditions and previous antimicrobial drug exposure are thus predictive of colonization, and a large percentage of these patients have subsequent positive clinical cultures for ESBL-producing bacteria.
authors.affiliation: Department of Epidemiology and Preventive Medicine, School of Medicine, University of Maryland, Baltimore 21201, USA. aharris@epi.umaryland.edu
authors.forename: Anthony D
authors.initials: AD
authors.lastname: Harris
authors.forename: Jessina C
authors.initials: JC
authors.lastname: McGregor
authors.forename: Judith A
authors.initials: JA
authors.lastname: Johnson
authors.forename: Sandra M
authors.initials: SM
authors.lastname: Strauss
authors.forename: Anita C
authors.initials: AC
authors.lastname: Moore
authors.forename: Harold C
authors.initials: HC
authors.lastname: Standiford
authors.forename: Joan N
authors.initials: JN
authors.lastname: Hebden
authors.forename: J Glenn
authors.initials: JG
authors.lastname: Morris
mesh_terms: D000368:Aged; D015331:Cohort Studies; D003430:Cross-Sectional Studies; D024901:Drug Resistance, Multiple, Bacterial; D004926:Escherichia coli / Q000187:drug effects / Q000201:enzymology* / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000188:drug therapy / Q000382:microbiology*; D005260:Female; D006801:Humans; D007362:Intensive Care Units; D007709:Klebsiella / Q000187:drug effects / Q000201:enzymology* / Q000302:isolation & purification; D007710:Klebsiella Infections / Q000188:drug therapy / Q000382:microbiology*; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D011446:Prospective Studies; D012307:Risk Factors; D018440:beta-Lactam Resistance; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D001618:beta-Lactamases