Extended-Spectrum Beta-Lactamase-Producing Bacteria in a Urology Ward: Epidemiology, Risk Factors and Antimicrobial Susceptibility Patterns.

INTRODUCTION: Our aim was to describe the incidence and risk factors associated with extended-spectrum beta-lactamase (ESBL)-producing Enterobacteriaceae and their resistance rate in a urological ward.

MATERIAL AND METHODS: We carried out a prospective observational study from November 2011 to December 2014, reviewing healthcare-associated infections (HAIs) in our department. We evaluated the infections caused by ESBL-producing Enterobacteriaceae.

RESULTS: The incidence of HAIs in our urology ward was 6.8%. Enterobacteriaceae including Escherichia coli (24.9%), Klebsiella spp. (12.1%), Enterobacter spp. (5.9%), Morganella spp. (1.5%), Proteus spp. (1.5%), and Citrobacter spp. (1.5%) represented 47.4% of the isolated pathogens. The percentage of ESBL-producing Enterobacteriaceae was 26.4. Risk factors associated with a higher incidence of ESBL-producing bacteria were prior urinary tract infection (UTI; p < 0.001), hypertension (p = 0.042), immunosuppression (p = 0.004), and urinary stone (p = 0.027). The multivariable analysis confirmed prior UTI, immunosuppression and urinary stone as risk factors. ESBL-producing strains showed resistance rates of 85.3% for fluoroquinolones and 11.8% for carbapenems. Moreover, 16.7% of ESBL-Klebsiella were resistant to carbapenems.

CONCLUSIONS: ESBL-producing enterobacteria are associated with higher cross resistance to antibiotics such as quinolones. Higher resistance rates are reported in ESBL-producing Klebsiella. Among patients admitted in a urology ward, risk factors for ESBL-producing strains were previous UTI, immunosuppression, and urinary stone.