Clinical Impact and Risk Factors of Nonsusceptibility to Third-Generation Cephalosporins Among Hospitalized Adults with Monomicrobial Enterobacteriaceae Bacteremia in Southern Taiwan: A Multicenter Study

Reducing the effectiveness of broad-spectrum cephalosporins against infections has been recognized. This study aimed to investigate risk factors and clinical significance of third-generation cephalosporin nonsusceptibility (3GC-NS) among the cases of monomicrobial bacteremia (mEB) at regional or district hospitals. The study was conducted at three hospitals in southern Taiwan between Jan. 2017 and Oct. 2019. Only the first episode of mEB from each adult (aged ≥20 years) was included. The primary outcome was in-hospital crude mortality. Overall there were 499 episodes of adults with mEB included, and their mean age was 74.5 years. Female predominated, accounting for 53% of all patients. (62%) and (21%) were two major causative species. The overall mortality rate was 15% (73/499), and patients infected by 3GC-NS isolates (34%, 172/499) had a higher mortality rate than those by 3GC-susceptible isolates (66%, 327/499) (21% vs 11%, =0.005). By the multivariate analysis, 3GC-NS was the only independent prognostic determinant (adjusted odds ratio [AOR], 1.78; =0.04). Of note, male (AOR 2.02, =0.001), nosocomial-acquired bacteremia (AOR 2.77,