Document resource
Background and Importance Ceftazidime/avibactam (CZA) is a combination antibiotic considered restricted use due to the low prevalence of resistance. Its use is justified as targeted therapy for infections caused by multidrug-resistant Gram-negative aerobic bacteria, in accordance with the hospital’s antimicrobial stewardship program (ASP) protocol.Aim and Objectives To evaluate the evolution of CZA prescribing after the consolidation of an ASP in a tertiary hospital, comparing two periods and assessing the appropriateness of therapy.Material and Methods Observational, retrospective, and descriptive study of CZA use across two periods (December 2021–December 2022 and December 2023–June 2025), including 46 and 40 patients, respectively, in a tertiary hospital.Data collected from medical records included sex, age, prescribing service, microorganism, type of therapy (empirical or targeted), microbiological isolation, indication, and clinical outcome.Results A total of 46 patients were analysed in Period 1 and 40 in Period 2. The values of the included variables were: female patients 26% vs. 32%; mean age 60.17±15.64 vs. 56±18.27 years, respectively; mortality 35% vs. 26%.Empirical treatments accounted for 52% vs. 38%, of which non-resistant cases represented 37% vs. 26%. Treatments with prior microbiological isolation were 48% vs. 62%, prescriptions by the Infectious Diseases service were 10% vs. 22%. Targeted CZA prescriptions against multidrug-resistant Gram-negative bacteria accounted for 28% vs. 55%. Targeted treatments of period 1 20% of Gram-positive1 Staphilococcus petrasii 5 Stahilococcus epidermidis SARM2 Staphilococcus haemoliticum SARM1 Staphilococcus aureus SARM28% of Gram-negative7 Pseudomonas aeruginosa mR1 Escherichia coli OXA-481 Klebsiella pneumoniae BLEA1 Enterococcus faecium VanR3 Stenotrophomonas maltophila Targeted treatments of period 2 7% of Gram-positive2 Enterococcus faecium 55% of Gram-negative9 Pseudomonas aeruginosa mR1 Escherichia coli BLEE2 Klebsiella pneumoniae BLEE1 Klebsiella. pneumoniae OXA-482 Stenotrophomonas maltophila Conclusion and Relevance The study evidenced a 27% improvement in prescription appropriateness after ASP consolidation of implemented measures, including daily multidisciplinary team meetings and online alerts from the ASP, although empirical use and prescriptions for Gram-positive isolates remain outside hospital protocol.CZA is regarded as an antibiotic of very restricted use, reserved for situations with antibiogram confirmation or sepsis codes involving multidrug-resistant Gram-negative organisms.Conflict of Interest No conflict of interest