title: Implementing an intensified antibiotic stewardship programme targeting daptomycin use in orthopaedic surgery: a cost-benefit analysis from the hospital perspective.
abstract: BACKGROUND
  Hospital antibiotic stewardship (ABS) programmes offer several evidence-based tools to control prescription rates of antibiotics in different settings, influence the incidence of nosocomial infections and to contain the development of multi-drug-resistant bacteria. In the context of endoprosthetic surgery, however, knowledge of core antibiotic stewardship strategies, comparisons of costs and benefits of hospital ABS programmes are still lacking.
  
  
  METHODS
  We identified a high daptomycin use for the treatment of methicillin-sensitive staphylococcal infections as a potential target for our ABS intervention. In addition, we endorsed periprosthetic tissue cultures for the diagnosis of PJI. Monthly antibiotic use data were obtained from the hospital pharmacy and were expressed as WHO-ATC defined daily doses (DDD) and dose definitions adapted to local guidelines (recommended daily doses, RDD), normalized per 1000 patient days. The pre-intervention period was defined from February 2012 through January 2014 (24 months). The post-intervention period included monthly time points from February 2014 to April 2015 (15 months). For a basic cost-benefit analysis from the hospital perspective, three cost drivers were taken into account: (1) the cost savings due to changes in antimicrobial prescribing; (2) costs associated with the increase in the number of cultured tissue samples, and (3) the appointment of an infectious disease consultant. Interrupted time-series analysis (ITS) was applied.
  
  
  RESULTS
  Descriptive analysis of the usage data showed a decline in overall use of anti-infective substances in the post-intervention period (334.9 vs. 221.4 RDDs/1000 patient days). The drug use density of daptomycin dropped by -75 % (51.7 vs. 12.9 RDD/1000 patient days), whereas the utilization of narrow-spectrum penicillins, in particular flucloxacillin, increased from 13.8 to 33.6 RDDs/1000 patient days. ITS analysis of the consumption dataset showed significant level changes for overall prescriptions, as well as for daptomycin (p < 0.001) and for narrow-spectrum penicillins (p = 0.001). The total costs of antibiotic consumption decreased by an estimated € 4563 per month (p < 0.001), and around 90 % of these savings were linked to a decrease in daptomycin consumption. Overall, the antibiotic stewardship programme was beneficial, as monthly cost savings of € 2575 (p = 0.005) were achieved.
  
  
  CONCLUSIONS
  In this example of large endoprosthetic surgery department in a community-based hospital, the applied hospital ABS programme targeting daptomycin use has shown to be feasible, effective and beneficial compared to no intervention.
authors.affiliation: Sektion Infektiologie, Medizinische Klinik, Ortenauklinikum Achern, Josef-Wurzler-Straße 7, 77855, Achern, Germany. johannes.borde@web.de.|Division of Infectious Diseases, Department of Medicine, University Medical Center, 79106, Freiburg i.Br., Germany. johannes.borde@web.de.
authors.forename: Johannes P
authors.initials: JP
authors.lastname: Borde
authors.affiliation: Zentralapotheke, Ortenauklinikum Offenburg-Gengenbach, Ebertplatz 12, 77654, Offenburg, Germany.
authors.forename: Sarah
authors.initials: S
authors.lastname: Nussbaum
authors.affiliation: Zentralapotheke, Ortenauklinikum Offenburg-Gengenbach, Ebertplatz 12, 77654, Offenburg, Germany.
authors.forename: Stefanie
authors.initials: S
authors.lastname: Hauser
authors.affiliation: Center for Medical Biometry and Informatics, University Medical Center, 79106, Freiburg i.Br., Germany.
authors.forename: Philip
authors.initials: P
authors.lastname: Hehn
authors.affiliation: Division of Pediatric Infectious Diseases, Department of Pediatrics, von Haunersches Kinderspital, 80337, Munich, Germany.
authors.forename: Johannes
authors.initials: J
authors.lastname: Hübner
authors.affiliation: MVZ Clotten Labor Dr.Haas, Dr.Raif and Kollegen GbR, Merzhauser Str. 112a, 79100, Freiburg i.Br., Germany.
authors.forename: Gabriela
authors.initials: G
authors.lastname: Sitaru
authors.affiliation: Abteilung für Endoprothetik, Ortenauklinikum Offenburg-Gengenbach, Leutkirchstraße 32, 77723, Gengenbach, Germany.
authors.forename: Sebastian
authors.initials: S
authors.lastname: Köller
authors.affiliation: Abteilung für Endoprothetik, Ortenauklinikum Offenburg-Gengenbach, Leutkirchstraße 32, 77723, Gengenbach, Germany.
authors.forename: Bruno
authors.initials: B
authors.lastname: Schweigert
authors.affiliation: Universitätsklinikum Carl Gustav Carus, Zentralbereich Infektiologie, Fetscherstraße 74, 01307, Dresden, Germany.
authors.forename: Katja
authors.initials: K
authors.lastname: deWith
authors.affiliation: Division of Infectious Diseases, Department of Medicine, University Medical Center, 79106, Freiburg i.Br., Germany.
authors.forename: Winfried V
authors.initials: WV
authors.lastname: Kern
authors.affiliation: Center for Medical Biometry and Informatics, University Medical Center, 79106, Freiburg i.Br., Germany.
authors.forename: Klaus
authors.initials: K
authors.lastname: Kaier
mesh_terms: D000900:Anti-Bacterial Agents / Q000008:administration & dosage / Q000191:economics / Q000627:therapeutic use; D003362:Cost-Benefit Analysis; D017576:Daptomycin / Q000008:administration & dosage / Q000191:economics / Q000627:therapeutic use; D006801:Humans; D019637:Orthopedic Procedures / Q000009:adverse effects / Q000191:economics; D010607:Pharmacy Service, Hospital / Q000191:economics / Q000592:standards; D016459:Prosthesis-Related Infections / Q000188:drug therapy / Q000191:economics / Q000517:prevention & control
chemical_list: D000900:Anti-Bacterial Agents; D017576:Daptomycin
keywords: Antibiotic stewardship; Cost–benefit analysis; Orthopaedic surgical care; PJI