4CPS-013 Optimisation of empirical use of ceftazidime/avibactam in a medium-complexity hospital: impact of antimicrobial stewardship programme multidisciplinary team interventions

<h3>Background and Importance</h3> Ceftazidime/avibactam is critical for managing multidrug-resistant infections. With rising antibiotic resistance, optimising its empirical use via Antimicrobial Stewardship Programme (ASP) interventions is crucial for improving treatment appropriateness and patient safety. <h3>Aim and Objectives</h3> To assess the appropriateness of empirical ceftazidime/avibactam prescriptions and recommendations from the Antimicrobial Stewardship Programme (ASP) team. <h3>Material and Methods</h3> A retrospective observational study was conducted, including empirical prescriptions of ceftazidime/avibactam between January and December 2023 at a medium-complexity hospital. Data were collected from the Hospital Pharmacy programme’s inpatient module and electronic health records, including variables: sex, age, origin from long-term care facilities or intermediate care hospitals (LTCF/ICH), history of infection or colonisation by carbapenemase-producing microorganisms (CPMs), treatment duration, infection focus, empirical treatment (ET) appropriateness, ASP intervention and acceptance, and treatment duration. The appropriateness of ET was evaluated based on guidelines from the Infectious Disease Commission. Statistical analysis was conducted using IBM SPSS-Statistics 29.0, with the McNemar test applied to analyse differences in time-dependent ordinal variables. <h3>Results</h3> 45 ETs with ceftazidime/avibactam were reviewed in 32 patients (19 men) with a median age of 82.1 years (IQR 75.5–88.1). Of these, 46.9% (n=15) came from LTCF/ICH. A total of 43.8% (n=14) of patients had a positive colonisation study for CPM, 31.2% (n=10) had no history of CPM infection, and 25.0% (n=8) had a history of CPM infection but a negative colonisation study. The most frequent infection focus was urinary (48.9%), followed by respiratory (28.9%), skin and soft tissue (13.4%), abdominal (4.4%), surgical prophylaxis (2.2%), and unknown focus (2.2%). Additionally, 22.2% of patients had bacteraemia. ASP team reviewed 80% (n=36) of the ETs; all treatments exceeding 3 days were reviewed. Recommendations included: escalation to ceftazidime/avibactam (14/36), continuation of empirical therapy with ceftazidime/avibactam( 8/36), de-escalation (7/36), dosage adjustment for renal function (3/36), initiation of antibiotic therapy (2/36), and discontinuation (2/36). All recommendations were accepted (100%). Initially, 31.1%( 14/45) of ETs were deemed appropriate. Post-ASP intervention, appropriateness rose to 88.9% (40/45), with a statistically significant difference (p&lt;0.05). <h3>Conclusion and Relevance</h3> The study highlighted that elderly patients from LTCF/ICH, often with CPM-related histories, were the primary recipients of ceftazidime/avibactam ET in our hospital, with urinary infections most common. ASP interventions significantly improved treatment appropriateness, underscoring the critical role of the ASP in enhancing clinical practice and patient safety. The ASP team’s recommendations had an excellent acceptance rate. <h3>References and/or Acknowledgements</h3> <h3>Conflict of Interest</h3> No conflict of interest