Direct use of eazyplex ® SuperBug CRE assay from positive blood cultures in conjunction with inpatient infectious disease consulting for timely appropriate antimicrobial therapy in Escherichia coli and Klebsiella pneumoniae bloodstream infections

To describe a rapid workflow based on the direct detection of ( ) and ( ) producing CTX-M extended-spectrum β-lactamase (ESBL) and/or carbapenemases (eg, KPC, VIM) from blood cultures (BCs) and the infectious disease (ID) consulting for timely appropriate antimicrobial therapy. This observational, retrospective study included adult patients with a first episode of or bloodstream infection (BSI) in a large Italian university hospital, where an inpatient ID consultation team (IDCT) has been operational. Results from the BCs tested for detecting , , , , and genes by the eazyplex SuperBug CRE assay in and organisms had been notified for antimicrobial therapy consulting. In 321 BSI episodes studied, we found that 151 (47.0%) of or organisms harbored and/or and/or (meantime from BC collection: 18.5 h). Empirical antimicrobial treatment was appropriate in 21.8% (33/151) of BSIs, namely 5.9% (3/51) of BSIs caused by KPC/VIM producers and 30.0% (30/100) of BSIs caused by CTX-M producers. After notification of results, the IDCT modified antimicrobial therapy (mean time from BC collection: 20 h) such that the proportion of appropriate treatments increased to 84.8% (128/151) of BSIs, namely 70.6% (36/51) of BSIs caused by KPC/VIM producers and 92.0% (92/100) of BSIs caused by CTX-M producers. Our study shows that a rapid diagnostic-driven clinical strategy allowed for early prescription of potentially effective antimicrobial therapy in BSIs caused by CTX-M ESBL- and/or KPC/VIM carbapenemase-producing and organisms.