4CPS-056 Mapping antibiotic use patterns in a septic orthopaedic ward

Background The Septic Ward treats patients with bone-, joint- and prosthetic-joint infections. The treatment of these infections requires complex, long-term antibiotic therapies. Clinical pharmacy services were introduced in 2015. This included revision of antimicrobial therapies and surveillance of antibiotic consumption. Purpose The aim of the study was to analyse antibiotic use and microbiological data in the ward between 2010 and 2017. Material and methods Data was collected on systemic antibiotics dispensed from the pharmacy’s database. Both WHO defined daily dose (DDD) and prescribed daily dose (PDD) methods were used to analyse the antibiotic consumption, standardised to 100 patient days. PDDs were defined according to therapeutic guidelines and revised by infectologists. Microbiological data were collected from the Microbiology Department’s database. Results The cost of antibiotics accounts for 65% of all pharmaceutical expenses between 2010 and 2017. Twenty-eight antibacterial agents were used in 2017, 30 in 2013 and 2010. In 2017, 11 agents were responsible for the DU90% segment of the consumption. Most extensively used agents were amoxicillin-clavulanic-acid, cefuroxime and ciprofloxacin. There was a significant difference between the results of DDD-PDD analyses. The utilisation of clindamycin (14.48 DDD/100 patient days in 2013 vs. 2.99 in 2017 – the same in PDDs) and ceftriaxone (3.61 vs. 0.31 DDD/100 patient days – the same in PDDs) decreased notably, while the use of narrow-spectrum beta-lactams increased in the past 3 years (from 2.93 to 7.84 DDD/100 patient days – 1.12 vs. 4.13 PDD/100 patient days), which was an initial goal of the pharmacists’ interventions. Microbiological data showed an increased rate of multiresistant pathogens, especially Vancomycin-resistant E. faecium (0 in 2010, two in 2013 and 14 in 2017), resulting in increased consumption of reserve antibiotics such as linezolid (no use until 2015, 0.23 DDD/100 patient days in 2017) and tigecycline (no use until 2013, 0.28 DDD/100 patient days in 2017). Conclusion Monitoring the use of antibiotics and comparing results with microbiological data provides a range of local resistance conditions, which are fundamental to antimicrobial guideline development. The data highlights desirable trends and critical points, allowing pharmacists to feedback to prescribers and emphasise the value of their interventions. Interpretation of results must account for the fact that the generally accepted DDD method can be incorrect due to differences in antibiotic dosing. References and/or acknowledgements https://www.idsociety.org/practice-guideline/prosthetic-joint-infection/https://www.whocc.no/atc_ddd_index/ No conflict of interest.