title: Carbapenem stewardship: positive impact on hospital ecology.
abstract: BACKGROUND
  Excessive group 2 carbapenem use may result in decreased bacterial susceptibility.
  
  
  OBJECTIVE
  We evaluated the impact of a carbapenem stewardship program, restricting imipenem and meropenem use.
  
  
  METHODS
  Ertapenem was mandated for ESBL-producing Enterobacteriaceae infections in the absence of non-fermenting Gram-negative bacilli (GNB) from April 2006 to March 2008. Group 2 carbapenems were restricted for use against GNB infections susceptible only to carbapenems and suspected GNB infections in unstable patients. Cumulative susceptibility tests were done for nosocomial pathogens before and after restriction using Clinical and Laboratory Standards Institute (CLSI) guide-lines.Vitek System or conventional identification methods were performed and susceptibility testing done by disk diffusion according to CLSI.Antibiotic consumption (t-test) and susceptibilities (McNemar's test) were determined.
  
  
  RESULTS
  The defined daily doses (DDD) of group 2 carbapenems declined from 61.1 to 48.7 DDD/1,000 patient-days two years after ertapenem introduction (p = 0.027). Mean ertapenem consumption after restriction was 31.5 DDD/1,000 patient-days. Following ertapenem introduction no significant susceptibility changes were noticed among Gram-positive cocci. The most prevalent GNB were P. aeruginosa, Klebsiella pneumoniae, and Acinetobacter spp. There was no change in P. aeruginosa susceptibility to carbapenems. Significantly improved P. aeruginosa and K. pneumoniae ciprofloxacin susceptibilities were observed, perhaps due to decreased group 2 carbapenem use. K. pneumoniae susceptibility to trimethoprim-sulfamethoxazole improved.
  
  
  CONCLUSIONS
  Preferential use of ertapenem resulted in reduced group 2 carbapenem use, with a positive impact on P. aeruginosa and K. pneumoniae susceptibility.
authors.affiliation: Institute of Orthopedics and Traumatology Infection Control Service, Hospital das Clínicas, School of Medicine, Universidade de São Paulo, SP, Brazil. ccih.iot@hcnet.usp.br
authors.forename: Ana Lucia Lei Munhoz
authors.initials: AL
authors.lastname: Lima
authors.forename: Priscila Rosalba Domingos de
authors.initials: PR
authors.lastname: Oliveira
authors.forename: Adriana Pereira de
authors.initials: AP
authors.lastname: Paula
authors.forename: Karine
authors.initials: K
authors.lastname: Dal-Paz
authors.forename: João Nóbrega de
authors.initials: JN
authors.lastname: Almeida
authors.forename: Cássia da Silva
authors.initials: Cda S
authors.lastname: Félix
authors.forename: Flávia
authors.initials: F
authors.lastname: Rossi
mesh_terms: D000150:Acinetobacter / Q000187:drug effects*; D000900:Anti-Bacterial Agents / Q000008:administration & dosage*; D015780:Carbapenems / Q000008:administration & dosage*; D003428:Cross Infection / Q000188:drug therapy* / Q000382:microbiology; D004755:Enterobacteriaceae / Q000187:drug effects*; D000077727:Ertapenem; D006801:Humans; D015378:Imipenem / Q000008:administration & dosage; D000077731:Meropenem; D008826:Microbial Sensitivity Tests; D011550:Pseudomonas aeruginosa / Q000187:drug effects*; D013845:Thienamycins / Q000008:administration & dosage; D047090:beta-Lactams / Q000008:administration & dosage
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D013845:Thienamycins; D047090:beta-Lactams; D015378:Imipenem; D000077731:Meropenem; D000077727:Ertapenem