Distribution and antibiotic resistance profile of key gram-negative bacteria that cause community-onset urinary tract infections in the Russian Federation: RESOURCE multicentre surveillance 2017 study

Abstract Background Urinary tract infections (UTIs) are among the most common bacterial infections in clinical practice. The aim of the RESOURCE study was to determine the antimicrobial resistance profile of gram-negative bacteria isolated from outpatient urine samples collected across the Russian Federation. Methods A total of 96,781 urine samples were collected from 520 cities of the Russian Federation between January 1 and December 31, 2017. Antibiotic susceptibility was performed using semi-automated analysers. The mean age of the study population was 40.9 years, 80.2% were female and 19.8% were male. Findings Of the uropathogens isolated, 64.2% were gram-negative bacteria. Among these, Escherichia coli was the most common (49.1%), followed by Klebsiella pneumoniae (9.5%), Proteus mirabilis (2.9%), Pseudomonas aeruginosa (1.7%) and Enterobacter spp. (1.0%). Of the antibiotics tested, 50% of the isolated E. coli strains were resistant to ampicillin, followed by co-trimoxazole (30.3%), aztreonam (26.2%), levofloxacin (28.8%) and cefuroxime (21%). Conversely, E. coli were highly susceptible to imipenem (0.7% resistant strains isolated), amikacin (0.9%), nitrofurantoin (4.5%) and fosfomycin (1.2%). The most active antimicrobials against K. pneumoniae were imipenem (6.8% resistant strains) and colistin (0.5%), while piperacillin/tazobactam (4.2%), cefoperazone/sulbactam (3.1%) and imipenem (0%) were the most active agents against P. mirabilis. The antimicrobials showing the highest activity against P. aeruginosa were colistin (10.7% resistant strains) and aztreonam (0%), while piperacillin/tazobactam (7.1%) and cefoperazone/sulbactam (2.3%) showed the highest activity against Enterobacter spp. Interpretation The prevalence of fluoroquinolone and cephalosporin resistance among common UTI-causing gram-negative bacteria highlights the growing challenge of successfully treating community-onsetUTIs.