Incidence and antimicrobial resistance trends in bloodstream infections caused by ESKAPE and Escherichia coli at a large teaching hospital in Rome, a 9-year analysis (2007–2015)

The proportion of antimicrobial resistance (AMR) among the ESKAPE and Escherichia coli (ESKAPEEc) pathogens causing bloodstream infection (BSI) increased worldwide. We described longitudinal trends in ESKAPEEc BSI and AMR over 9 years (2007–2015) at a large teaching hospital in Italy. Of 9720 unique BSI episodes, 6002 (61.7%) were caused by ESKAPEEc pathogens. The majority of these episodes (4374; 72.9%) were hospital-onset infections. The most frequent pathogen was E. coli (32.8%), followed by Staphylococcus aureus (20.6%), Klebsiella pneumoniae (16.1%), and Pseudomonas aeruginosa (11.6%). There was a significant increase of hospital-onset K. pneumoniae (from 2.3 to 5.0 per 10,000 patient-days; P = 0.001) and community-onset E. coli (from 3.3 to 9. 1 per 10,000 emergency admissions; P = 0.04) BSIs. Among hospital-onset BSIs, increases of extended-spectrum β-lactamase (ESBL)-producing E. coli (from 25.4 to 35.2%, P = 0.006), carbapenemase-producing K. pneumoniae (from 4.2 to 51.6%, P < 0.001), and methicillin-resistant S. aureus (from 33.9 to 44.4%, P < 0.001) BSIs were observed between the 2007–2009 and 2010–2012 study periods. In contrast, a decrease of BSIs caused by P. aeruginosa resistant to ceftazidime (from 45.5 to 28.2%, P < 0.001), ciprofloxacin (from 46 to 36.3%, P = 0.05), and meropenem (from 55 to 39.9%, P = 0.03) was observed through all 9 years of the study period. Among community-onset BSIs, increases of BSIs caused by ESBL-producing E. coli (from 28.6 to 42.2%, P = 0.002) and carbapenemase-producing K. pneumoniae (from 0 to 17.6%) were observed between the 2007–2009 and 2010–2012 study periods. Our findings show increased rates of BSI and relative AMR for specific pathogen-health care setting combinations, and call for continued active surveillance and infection control policies.