Impact of interventions by an antimicrobial stewardship program team on appropriate antimicrobial therapy in patients with bacteremic urinary tract infection

Abstract Background Inappropriate antimicrobial therapy often leads to poor outcomes. This study aimed to evaluate the impact of an antimicrobial stewardship program (ASP) team on appropriate therapy, in patients with bacteremic urinary tract infection (UTI). Patients and methods We retrospectively reviewed the interventions by the ASP team in 807 patients with bacteremic UTI. Interventions were divided into 3 groups: group A (conventional report), group B (conventional report and written alert on the chart), and group C (conventional report and oral recommendation with/without written alert). The appropriateness of antimicrobial therapy was assessed at 2 time points, based on blood culture results. Results The ASP team estimated that 166 and 576 patients received inappropriate antimicrobial therapy based on the results of Gram staining, and final report, respectively. Appropriate therapy after intervention was administered to 53.2% of group A, 63.5% of group B, and 89.3% of group C patients, respectively. Mortality was significantly lower in patients of de-escalation than in those with no antimicrobial changes, without prolonged hospital stay. Conclusion This study provides one plausible benchmark for appropriate antimicrobial therapy by ASP, while observer bias and survivor treatment selection bias exist, and further studies including evaluation for severity are needed.