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

Background: 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.

Methods: 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.

Results: 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, <0.001), and usage of nasogastric tube (AOR 2.01, =0.002) were positively associated with 3GC-NS, but bacteremia (AOR 0.28, =0.01) and age (AOR 0.98, =0.04) negatively with 3GC-NS.

Conclusion: For adults with bacteremia, 3GC-NS signifies a significant prognostic impact. Efforts to rapid identification of such antimicrobial resistance profiles should be incorporated into antimicrobial stewardship programs to achieve favorable outcomes.