title: Effects of Group 1 versus Group 2 carbapenems on the susceptibility of Acinetobacter baumannii to carbapenems: a before and after intervention study of carbapenem-use stewardship.
abstract: OBJECTIVE
  Antimicrobial stewardship programs have been proposed for reducing bacterial resistance in the hospital environment. The purpose of this study was to investigate the impact of a carbapenem-use stewardship program on the susceptibility of Acinetobacter baumannii to Group 2 carbapenems.
  
  
  METHODS
  A before and after intervention study was conducted at a university hospital from September 2008 to February 2013. Three study periods were defined: Phase I, pre-intervention (months 1-18); Phase II, a postintervention period during which ertapenem use was mandated but carbapenem use was not restricted (months 19-36); and Phase III, a postintervention period during which Group 2 carbapenem use was restricted (months 37-54).
  
  
  RESULTS
  During the study period, intervention resulted in diminished consumption of Group 2 carbapenems (antimicrobial use density (AUD): 21.3±6.0 in Phase I, 18.8±6.0 in Phase II, 16.1±4.4 in Phase III; P = 0.028) and increased consumption of ertapenem (AUD: 2.7±1.7 in Phase I, 7.2±4.5 in Phase II, 9.1±5.3 in Phase III; P<0.001). The use of autoregressive-error models showed that in contrast with ertapenem use, the use of Group 2 carbapenem during the previous one month was positively and significantly associated with a subsequent increase in the proportion of carbapenem-resistant A. baumannii (CRAB) (P = 0.031).
  
  
  CONCLUSIONS
  Implementing a carbapenem-use stewardship program featuring the preferential use of ertapenem for treating appropriate indications of infection resulted in reduced use of Group 2 carbapenems and had a positive impact on the susceptibility of A. baumannii to carbapenems. This approach could be integrated into CRAB-control strategies in hospitals.
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea; Institute of Emerging Infectious Diseases, Korea University College of Medicine, Seoul, Republic of Korea; Infection Control Unit, Korea University Anam Hospital, Seoul, Republic of Korea.
authors.forename: Young Kyung
authors.initials: YK
authors.lastname: Yoon
authors.affiliation: Department of Biostatistics, Korea University College of Medicine, Seoul, Republic of Korea.
authors.forename: Kyung Sook
authors.initials: KS
authors.lastname: Yang
authors.affiliation: Infection Control Unit, Korea University Anam Hospital, Seoul, Republic of Korea.
authors.forename: Seung Eun
authors.initials: SE
authors.lastname: Lee
authors.affiliation: Infection Control Unit, Korea University Anam Hospital, Seoul, Republic of Korea.
authors.forename: Hyun Jeong
authors.initials: HJ
authors.lastname: Kim
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea; Institute of Emerging Infectious Diseases, Korea University College of Medicine, Seoul, Republic of Korea; Infection Control Unit, Korea University Anam Hospital, Seoul, Republic of Korea.
authors.forename: Jang Wook
authors.initials: JW
authors.lastname: Sohn
authors.affiliation: Division of Infectious Diseases, Department of Internal Medicine, Korea University College of Medicine, Seoul, Republic of Korea; Institute of Emerging Infectious Diseases, Korea University College of Medicine, Seoul, Republic of Korea; Infection Control Unit, Korea University Anam Hospital, Seoul, Republic of Korea.
authors.forename: Min Ja
authors.initials: MJ
authors.lastname: Kim
mesh_terms: D000151:Acinetobacter Infections / Q000188:drug therapy*; D040981:Acinetobacter baumannii / Q000187:drug effects*; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D015780:Carbapenems / Q000494:pharmacology*; D024881:Drug Resistance, Bacterial; D000077727:Ertapenem; D006801:Humans; D008826:Microbial Sensitivity Tests; D047090:beta-Lactams / Q000494:pharmacology
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D047090:beta-Lactams; D000077727:Ertapenem