Bacterial and fungal pathogens isolated from patients with bloodstream infection: frequency of occurrence and antimicrobial susceptibility patterns from the SENTRY Antimicrobial Surveillance Program (2012–2017)

Abstract

The SENTRY Antimicrobial Surveillance Program has monitored bloodstream infections (BSIs) from patients in medical centers worldwide since 1997. In this report, we examine the frequency of occurrence and antimicrobial susceptibility profiles of 6741 bacterial and 222 fungal pathogens causing BSI in 16 medical centers from 2012 to 2017. These results were stratified according to patient age, intensive care unit (ICU) location, and hospital onset (HO) versus community onset (CO) of infection. The leading pathogen isolated from patients in all age groups (range, 20.3–32.5%), except for those >64 years old (19.9%), was Staphylococcus aureus. Escherichia coli was the most common agent in patients over 64 years of age (26.7%). S. aureus was frequently recovered from patients with HO or CO BSI (20.9–24.1%). However, E. coli was the most commonly isolated species (24.5%) from CO infections. BSIs caused by vancomycin-resistant enterococci, penicillin-nonsusceptible S. pneumoniae, extended-spectrum β-lactamase–producing Klebsiella spp., carbapenem-resistant Enterobacteriaceae, and multidrug-resistant Pseudomonas aeruginosa were more common among patients in ICUs compared to patients hospitalized in a non-ICU setting. The frequency of methicillin-resistant S. aureus (MRSA) was slightly higher in the non-ICU population (37.5%) compared with the ICU group (34.1%). A trend toward a decrease in BSIs due to Gram-positive cocci and an increase in infections with Gram-negative bacilli were observed. Overall, the frequency of resistant phenotypes was high for S. aureus (MRSA; 37.0%), enterococci (vancomycin-resistant enterococci; 24.6%), Klebsiella spp. (extended-spectrum β-lactamase phenotype; 21.5%), and P. aeruginosa (multidrug-resistant; 15.4%) and generally declined from 2012 to 2017, whereas the frequency of penicillin-nonsusceptible Streptococcus pneumoniae (3.4%) and carbapenem-resistant Enterobacteriaceae (1.5%) was low overall and both resistant phenotypes declined over time. Fluconazole-resistant Candida spp. isolates were only detected in years 2013–2015.