title: Resistance to extended-spectrum cephalosporins and mortality in patients with Citrobacter freundii bacteremia.
abstract: BACKGROUND
  This study was performed to characterize the clinical features and to identify the risk factors for resistance to extended-spectrum cephalosporins (ESCs) and for mortality in patients with Citrobacter freundii bacteremia.
  
  
  METHODS
  105 patients (aged > or = 15 years) with C. freundii bacteremia in 1991-2000 were retrospectively analyzed.
  
  
  RESULTS
  Nosocomial acquisition was identified in 78.1% of the patients. Hepatic, biliary and pancreatic disease was the most common underlying disease (65.7%) and the biliary tract was the most common site of infection (50.5%). The overall resistance rate to ESCs was 59.0% and was significantly associated with hepatic, biliary and pancreatic disease, recent surgery and procedure, biliary drainage catheter and previous antibiotic therapy in univariate analysis. However, only previous antibiotic therapy with ESCs (OR = 5.0, 95% CI 1.6-15.7, p = 0.006) and recent surgery or procedure (OR = 3.1, 95% CI 1.1-8.4, p = 0.03) were strong, independent risk factors in multivariate analysis. Mortality directly related to C. freundii bacteremia was 21.9% and there was no difference between cases with resistance and susceptibility to ESCs (19.4% vs 25.6%; p = 0.45). Mortality was significantly associated with rapidly fatal or ultimately fatal underlying disease, a solid tumor, septic shock and polymicrobial bacteremia in univariate analysis. Among patients who had therapeutic surgical procedures, mortality was lower (4.5%, p = 0.04). Multivariate analysis revealed rapidly or ultimately fatal disease, septic shock and polymicrobial bacteremia as independent prognostic factors.
  
  
  CONCLUSIONS
  Biliary infection was the leading cause of C. freundii bacteremia. Previous antibiotic therapy, especially with ESCs, frequently predisposed for resistance to these antibiotics. However, resistance to ESCs was not associated with increased mortality.
authors.affiliation: Division of Infectious Diseases, Keimyung University Dongsan Medical Center, Daegu, Korea.
authors.forename: B N
authors.initials: BN
authors.lastname: Kim
authors.forename: J H
authors.initials: JH
authors.lastname: Woo
authors.forename: J
authors.initials: J
authors.lastname: Ryu
authors.forename: Y S
authors.initials: YS
authors.lastname: Kim
mesh_terms: D000293:Adolescent; D000328:Adult; D000368:Aged; D000369:Aged, 80 and over; D000900:Anti-Bacterial Agents / Q000627:therapeutic use; D016470:Bacteremia / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality*; D002511:Cephalosporins / Q000494:pharmacology* / Q000627:therapeutic use; D016971:Citrobacter freundii / Q000187:drug effects* / Q000302:isolation & purification; D016001:Confidence Intervals; D004756:Enterobacteriaceae Infections / Q000175:diagnosis / Q000188:drug therapy* / Q000401:mortality*; D005260:Female; D005500:Follow-Up Studies; D006801:Humans; D008297:Male; D008826:Microbial Sensitivity Tests; D008875:Middle Aged; D015999:Multivariate Analysis; D016017:Odds Ratio; D011336:Probability; D012189:Retrospective Studies; D018570:Risk Assessment; D016019:Survival Analysis; D016896:Treatment Outcome
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins