title: Cefepime therapy for monomicrobial bacteremia caused by cefepime-susceptible extended-spectrum beta-lactamase-producing Enterobacteriaceae: MIC matters.
abstract: BACKGROUND
  Extended-spectrum ß-lactamase (ESBL)-producing Enterobacteriaceae isolates are important clinical pathogens. In addition, the efficacy of cefepime for such infections is controversial.
  
  
  METHODS
  We performed a retrospective study of monomicrobial bacteremia caused by ESBL producers at 2 medical centers between May 2002 and August 2007. The patients definitively treated with in vitro active cefepime (cases) were compared with those treated with a carbapenem (controls) in a propensity score-matched analysis to assess therapeutic effectiveness. The 30-day crude mortality is the primary endpoint.
  
  
  RESULTS
  A total of 178 patients were eligible for the study. Patients who received cefepime (n = 17) as definitive therapy were more likely to have a clinical failure (odds ratio [OR] 6.2; 95% confidence interval [CI], 1.7-22.5; P = .002), microbiological failure (OR 5.5; 95% CI, 1.3-25.6; P = .04), and 30-day mortality (OR 7.1; 95% CI, 2.5-20.3; P < .001) than those who received carbapenem therapy (n = 161). Multivariate regression revealed that a critical illness with a Pitt bacteremia score ≥ 4 points (OR 5.4; 95% CI, 1.4-20.9; P = .016), a rapidly fatal underlying disease (OR 4.4; 95% CI, 1.5-12.6; P = .006), and definitive cefepime therapy (OR 9.9; 95% CI, 2.8-31.9; P < .001) were independently associated with 30-day crude mortality. There were 17 case-control pairs in the propensity scores matched analysis. The survival analysis consistently found that individuals who received cefepime therapy had a lower survival rate (log-rank test, P = .016).
  
  
  CONCLUSIONS
  Based on the current Clinical and Laboratory Standards Institute susceptible breakpoint of cefepime (minimum inhibitory concentration ≤ 8 μg/mL), cefepime definitive therapy is inferior to carbapenem therapy in treating patients with so-called cefepime-susceptible ESBL-producer bacteremia.
authors.affiliation: Department of Internal Medicine, National Cheng Kung University Hospital and Medical College, Tainan, Taiwan.
authors.forename: Nan-Yao
authors.initials: NY
authors.lastname: Lee
authors.forename: Ching-Chi
authors.initials: CC
authors.lastname: Lee
authors.forename: Wei-Han
authors.initials: WH
authors.lastname: Huang
authors.forename: Ko-Chung
authors.initials: KC
authors.lastname: Tsui
authors.forename: Po-Ren
authors.initials: PR
authors.lastname: Hsueh
authors.forename: Wen-Chien
authors.initials: WC
authors.lastname: Ko
mesh_terms: D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use*; D016470:Bacteremia / Q000188:drug therapy* / Q000382:microbiology; D015780:Carbapenems / Q000627:therapeutic use*; D016022:Case-Control Studies; D000077723:Cefepime; D002511:Cephalosporins / Q000627:therapeutic use*; D004755:Enterobacteriaceae / Q000201:enzymology*; D004756:Enterobacteriaceae Infections / Q000188:drug therapy* / Q000382:microbiology; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D015999:Multivariate Analysis; D012189:Retrospective Studies; D016896:Treatment Outcome; D001618:beta-Lactamases / Q000378:metabolism*
chemical_list: D000900:Anti-Bacterial Agents; D015780:Carbapenems; D002511:Cephalosporins; D000077723:Cefepime; D001618:beta-Lactamases