Risk-factors for emerging bloodstream infections caused by extended-spectrum β-lactamase-producing Escherichia coli

Risk-factors for bloodstream infections caused by extended-spectrum beta-lactamase (ESBL)-producing Escherichia coli were investigated using an exploratory case-double control study in which 43 cases (70% producing CTX-M enzymes) were compared with: (i) 86 patients with bacteraemia caused by non-ESBL-producing E. coli; and (ii) 86 hospitalised patients. Previous follow-up as an outpatient, urinary catheterisation and use of oxyimino-beta-lactams or fluoroquinolones were independent risk-factors for ESBL-producing E. coli among patients with E. coli bacteraemia, and previous use of oxyimino-beta-lactams or fluoroquinolones were also independent risk-factors among hospitalised patients. These findings may help in identifying patients at greater risk for bloodstream infection caused by ESBL-producing E. coli in endemic areas.