Trends of quinolone-resistant and/or ESBL producing Escherichia coli isolated from community-acquired urinary tract infections
Escherichia coli (E. coli) is a most popular causative bacteria of community-acquired urinary tract infections (UTIs). Recent studies have showed an increase in the prevalence of resistant E. coli. We report the incidence of quinolone-resistant E. coli (QR-EC) and extended spectrum β-lactamase producing E. coli (ESBL-EC) isolated from UTIs.
Between October 2009 and June 2017, the clinical and microbial data of UTI patients, who E. coli(≥104CFUs/ml) was isolated, were collected. QR-EC was determined when their minimum inhibitory concentration of levofloxacin was 4 μg/mL or above. ESBL producing ability was determined by double disk method. The study period was separated in the first period (October 2009 - November 2012), middle period (December 2012 - March 2015) and the last period (April 2015 - June 2017). Chronologically, the prevalence of QR-EC and ESBL-EC isolated from UTI patients was studied.
In this study period, 1,083 strains of E. coli were isolated from UTI patients. Out of 1,083 strains, 314 strains were isolated from uncomplicated UTI and 769 strains were from complicated UTI. The overall prevalence of QR-EC and ESBL-EC were 28.9% and 13.6%, respectively. Chronologically, the prevalence of QR-EC in the first period, the second period and the last period were 25.2%, 32.3% and 31.0%, respectively and those of ESBL-EC were 10.1%, 13.7% and 19.4%, respectively. The prevalence of QR-EC and ESBL-EC among complicated UTI patients were 34.2% and 14.8%, respectively. Among uncomplicated UTI patients, the prevalence of QR-EC and ESBL-EC were 15.6% and 10.8%, respectively. Chronological study in uncomplicated UTI patients, the prevalence of QR-EC of the first period, the second period and the last period were 11.3%, 17.9%, 22.1%, respectively and those of ESBL-EC were 5.0%, 14.1%, 19.5%, respectively.
Among uncomplicated UTI patients, the isolation of QR-EC and ESBL-EC has been increasing in the last period and the prevalence of QR-EC and ESBL-EC were 22.1% and 19.5%, respectively. We have to pay attention to resistant E. coli when we choose antibiotics for the treatment in patients with uncomplicated UTI.