Assessment of De-Escalation of Empirical Antimicrobial Therapy in Medical Wards with Recognized Prevalence of Multi-Drug-Resistant Pathogens: A Multicenter Prospective Cohort Study in Non-ICU Patients with Microbiologically Documented Infection.

Antimicrobial resistance poses a major threat to human health worldwide and the implementation of antimicrobial stewardship programs (ASPs), including antimicrobial de-escalation (ADE), is a multifaceted tool for minimizing unnecessary or inappropriate antibiotic exposure. This was a prospective observational study of 142 non-Intensive Care Unit (ICU) patients with microbiologically documented infection who were initially administered empirical antimicrobial therapy and admitted to the medical wards of 6 tertiary-care hospitals in Greece from January 2017 to December 2018. Patients were divided into two groups, the ADE and non-ADE group, based on whether ADE was applied or not, respectively. Exploratory end-points were ADE feasibility, safety and efficacy. ADE was applied in 76 patients at a median time of 4 days (IQR: 3, 5). An increased likelihood of ADE was observed in patients with urinary tract (OR: 10.04, 95% CI: 2.91, 34.57; < 0.001), skin and soft tissue (OR: 16.28, 95% CI: 1.68, 158.08; = 0.016) and bloodstream infections (OR: 2.52, 95% CI: 1, 6.36; = 0.05). Factors significantly associated with higher rates of ADE were clarithromycin administration, diagnosis of urinary tract infection (UTI), isolation of , age and symptoms type on admission. Mortality was lower in the ADE group (18.4% vs. 30.3% < 0.1) and ADE was not significantly associated with the probability of death ( = 0.432). ADE was associated with favorable clinical outcomes and can be performed even in settings with high prevalence of multi-drug resistant (MDR) pathogens without compromising safety.