title: Cefmetazole for bacteremia caused by ESBL-producing enterobacteriaceae comparing with carbapenems.
abstract: ESBL (Extended spectrum beta-lactamase) producing enterobacteriaceae are challenging organisms with little treatment options. Carbapenems are frequently used, but the emergence of carbapenem resistant enterobacteriaceae is a concerning issue, which may hinder the use of carbapenems. Although cephamycins such as cefoxitin, cefmetazole or cefotetan are effective against ESBL-producers in vitro, there are few clinical data demonstrating effects against bacteremia caused by these organisms.
  
  
  
  We performed a retrospective observational study on cases of bacteremia caused by ESBL-producers to investigate the efficacy of cefmetazole compared with carbapenems. We also evaluated whether the trend of antibiotic choice changed over years.
  
  
  
  Sixty-nine patients (male 34, age 69.2 ± 14.4), including two relapse cases, were reviewed for this analysis. The most common causative organisms were Escherichia coli (64, 93 %), followed by Klebsiella pneumoniae and K. oxytoca (2 each, 4 %). The group that received carbapenem therapy (43, 62 %) had increased severity in the Pittsburgh Bacteremic score than the group that received cefmetazole therapy, (1.5 ± 1.5 vs 2.5 ± 2.1, p = 0.048), while analysis of other factors didn't reveal any statistical differences. Five patients in the carbapenem group and one patient in the cefmetazole group died during the observation period (p = 0.24). CTX-M-9 were predominant in this series (59 %). Infectious disease physicians initially recommended carbapenems at the beginning of the current research period, which gradually changed over time favoring the use of cefmetazole instead (p = 0.002).
  
  
  
  Cefmetazole may be safely given to patients with bacteremia caused by ESBL-producers as a definitive therapy, if one can select out relatively stable patients.
authors.affiliation: Division of Infectious Diseases Therapeutics, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan. chicco@f.email.ne.jp.|Department of Microbiology and Infectious Disease, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan. chicco@f.email.ne.jp.
authors.forename: Takahiko
authors.identifier: 0000-0001-6192-1653
authors.initials: T
authors.lastname: Fukuchi
authors.affiliation: Division of Infectious Diseases Therapeutics, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.|Department of Microbiology and Infectious Disease, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.
authors.forename: Kentaro
authors.initials: K
authors.lastname: Iwata
authors.affiliation: Department of Clinical Laboratory, Kobe University Hospital, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.
authors.forename: Saori
authors.initials: S
authors.lastname: Kobayashi
authors.affiliation: Department of Clinical Laboratory, Kobe University Hospital, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.
authors.forename: Tatsuya
authors.initials: T
authors.lastname: Nakamura
authors.affiliation: Division of Infectious Diseases Therapeutics, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.|Department of Microbiology and Infectious Disease, Kobe University Graduate School of Medicine, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.|Department of Clinical Laboratory, Kobe University Hospital, 7-5-2 Kusunokicho, Chuoku, Kobe, Hyogo, 650-0017, Japan.
authors.forename: Goh
authors.initials: G
authors.lastname: Ohji
mesh_terms: D000368:Aged; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology; D015780:Carbapenems / Q000627:therapeutic use*; D015311:Cefmetazole / Q000627:therapeutic use*; D024881:Drug Resistance, Bacterial; D004755:Enterobacteriaceae / Q000201:enzymology*; D004926:Escherichia coli / Q000302:isolation & purification; D005260:Female; D006801:Humans; D041121:Klebsiella oxytoca / Q000302:isolation & purification; D007711:Klebsiella pneumoniae / Q000302:isolation & purification; D008297:Male; D008875:Middle Aged; D012189:Retrospective Studies; D014552:Urinary Tract Infections / Q000188:drug therapy / Q000382:microbiology; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D015311:Cefmetazole; D001618:beta-Lactamases
keywords: Bacteremia; Cefmetazole; Cephamycin; ESBL; Extended spectrum beta-lactamase