Antimicrobial susceptibility of global inpatient urinary tract isolates of Escherichia coli: results from the Study for Monitoring Antimicrobial Resistance Trends (SMART) program: 2009-2010

Escherichia coli is the most important uropathogen. The Study for Monitoring Antimicrobial Resistance Trends program collected 1643 E. coli isolates in 2009-2010 from urinary tract infection (UTI) specimens of hospitalized patients in countries worldwide. Ertapenem and imipenem were the most active agents tested, inhibiting >98% of all E. coli phenotypes. Overall, 17.9% of isolates were extended-spectrum beta-lactamase (ESBL) producers. The highest ESBL rate was from the Asia/Pacific region (27.7%). Amikacin and piperacillin-tazobactam achieved 90% inhibition levels only for ESBL-negative isolates. Ciprofloxacin and levofloxacin were not effective for ESBL-positive isolates, with only 14.6% and 15.9% susceptible, respectively. These observations highlight the need for continued monitoring of susceptibility of E. coli isolated from hospitalized patients with UTIs.