title: Frequency and epidemiology of extended-spectrum β-lactamase-producing Enterobacteriaceae isolates susceptible to third-generation cephalosporins or to aztreonam.
abstract: OBJECTIVE
  We evaluated among 400 strains of extended-spectrum β-lactamase-producing Enterobacteriaceae (ESBLE) the rate of strains categorized as intermediate or resistant to 3rd generation cephalosporins or aztreonam according to the 2011 guidelines of the French Society of Microbiology Antibiogram Committee.
  
  
  METHODS
  MICs of cefotaxime, ceftazidime, cefepime or aztreonam were determined by the E-test method for isolates with susceptible zones to these antibiotics.
  
  
  RESULTS
  Overall, 109/400 (27.3%) isolates were susceptible to at least one of these 4 agents. Notably, 21.8% of Escherichia coli isolates were susceptible to ceftazidime, and 21.1% of Klebsiella pneumoniae isolates were susceptible to cefepime. Discrepancies between categorization by disk diffusion and MIC determination were observed for aztreonam and cefepime.
  
  
  CONCLUSIONS
  These results indicate alternatives to carbapenems for treating infections caused by ESBLE.
authors: Service de microbiologie, hôpital Beaujon, AP-HP, 100, boulevard du Général-Leclerc, 92110 Clichy, France. Electronic address: frederic.bert@bjn.aphp.fr.
authors: F
authors: F
authors: Bert
authors: Service de microbiologie, hôpital Beaujon, AP-HP, 100, boulevard du Général-Leclerc, 92110 Clichy, France.
authors: S
authors: S
authors: Bialek-Davenet
authors: Service de microbiologie, hôpital Beaujon, AP-HP, 100, boulevard du Général-Leclerc, 92110 Clichy, France.
authors: V
authors: V
authors: Leflon-Guibout
authors: Service de microbiologie, hôpital Beaujon, AP-HP, 100, boulevard du Général-Leclerc, 92110 Clichy, France.
authors: L
authors: L
authors: Noussair
authors: Service de microbiologie, hôpital Beaujon, AP-HP, 100, boulevard du Général-Leclerc, 92110 Clichy, France.
authors: M-H
authors: MH
authors: Nicolas-Chanoine
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D001398:Aztreonam / Q000494:pharmacology*; D002511:Cephalosporins / Q000494:pharmacology*; D004755:Enterobacteriaceae / Q000187:drug effects* / Q000201:enzymology* / Q000302:isolation & purification; D006801:Humans; D008826:Microbial Sensitivity Tests; D001618:beta-Lactamases / Q000096:biosynthesis*
chemical_list: D000900:Anti-Bacterial Agents; D002511:Cephalosporins; D001618:beta-Lactamases; D001398:Aztreonam
keywords: Aztreonam; Aztréonam; Céphalosporines de 3(e) génération; Enterobacteriaceae; Entérobactéries; Extended-spectrum β-lactamase; Third-generation cephalosporins; β-lactamase à spectre étendu