title: Real-time monitoring of antimicrobial use density to reduce antimicrobial resistance through the promotion of antimicrobial heterogeneity in a haematology/oncology unit.
abstract: BACKGROUND
  In haematology/oncology units, the frequent and heavy use of broad-spectrum antimicrobials can lead to outbreaks of antimicrobial resistance. Increasing antimicrobial heterogeneity might be a useful strategy for preventing such resistance.
  
  
  METHODS
  A real-time antimicrobial use density (AUD) monitoring system (RAMS) was developed to precisely assess antimicrobial heterogeneity. This study was prospectively conducted over a 39 month period and involved 970 patients. Patient-specific antimicrobial therapy with five carbapenems (meropenem, biapenem, panipenem/betamipron, imipenem/cilastatin and doripenem) and four non-carbapenems (piperacillin/tazobactam, ceftazidime, cefozopran and cefepime) was prescribed in the first 12 months. A first-line antimicrobial was selected from among nine antimicrobials according to a predetermined schedule for the next 15 months. AUD-based antimicrobial selection was implemented using the RAMS during the last 12 months. We compared our findings for the RAMS period with those for the other periods to determine the effects of RAMS-based AUD monitoring on antimicrobial resistance.
  
  
  RESULTS
  The mean absolute difference between the AUD values of carbapenems and non-carbapenems (AUD deviation) was 6.0% in the RAMS period (range 0.5%-15.8%) and antimicrobial heterogeneity (AUD deviation <10%) was achieved in 10 out of 12 months (83.3%). Furthermore, during the RAMS period, AUD deviation was significantly smaller and the frequency of outbreaks of antimicrobial-resistant strains other than Stenotrophomonas maltophilia was significantly decreased (from 7.9% to 3.5%; P < 0.01) compared with the other periods.
  
  
  CONCLUSIONS
  The longer period of stable antimicrobial heterogeneity achieved by the RAMS strengthened its preventive effects against antimicrobial resistance. Optimal antimicrobial heterogeneity based on real-time AUD monitoring could reduce the frequency of outbreaks of antimicrobial resistance.
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Shogo
authors.initials: S
authors.lastname: Murata
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Toshiki
authors.initials: T
authors.lastname: Mushino
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Hiroki
authors.initials: H
authors.lastname: Hosoi
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Kodai
authors.initials: K
authors.lastname: Kuriyama
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Miwa
authors.initials: M
authors.lastname: Kurimoto
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Juri
authors.initials: J
authors.lastname: Watanuki
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Akinori
authors.initials: A
authors.lastname: Nishikawa
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Takashi
authors.initials: T
authors.lastname: Sonoki
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan.
authors.forename: Hideki
authors.initials: H
authors.lastname: Nakakuma
authors.affiliation: Department of Haematology/Oncology, Wakayama Medical University, Wakayama, Japan nhanaoka@wakayama-med.ac.jp.
authors.forename: Nobuyoshi
authors.initials: N
authors.lastname: Hanaoka
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D001424:Bacterial Infections / Q000188:drug therapy*; D024881:Drug Resistance, Bacterial; D004363:Drug Utilization / Q000592:standards*; D005260:Female; D019337:Hematologic Neoplasms / Q000150:complications; D006801:Humans; D008297:Male; D008875:Middle Aged; D016134:Organizational Policy; D011446:Prospective Studies; D055815:Young Adult
chemical_list: D000900:Anti-Bacterial Agents