Cefotaxime for the detection of extended-spectrum β-lactamase or plasmid-mediated AmpC β-lactamase and clinical characteristics of cefotaxime-non-susceptible Escherichia coli and Klebsiella pneumoniae bacteraemia.
We investigated the performance of cefotaxime for the detection of extended-spectrum β-lactamase (ESBL) or plasmid-mediated AmpC β-lactamase (pAmpC) and the clinical characteristics of cefotaxime-non-susceptible Escherichia coli or Klebsiella pneumoniae (CTXNS-EK) bacteraemia. All of the consecutive bloodstream isolates between 2005 and 2010 in a Japanese university hospital were characterised using polymerase chain reaction (PCR). Risk factors and outcomes of CTXNS-EK were analysed by multivariate logistic regression analysis. We identified 58 CTXNS-EK (15.6%) from 249 E. coli and 122 K. pneumoniae. Cefotaxime with a minimum inhibitory concentration (MIC) of >1 μg/mL had a sensitivity of 98.3% and a specificity of 99.7% for the detection of ESBL or pAmpC. CTXNS-EK had increased from 4.5% in 2005 to 23% in 2009. Risk factors for CTXNS-EK were previous isolation of multidrug-resistant bacteria, use of oxyimino-cephalosporins or fluoroquinolones, and high Sequential Organ Failure Assessment (SOFA) score. Patients with CTXNS-EK bacteraemia less frequently received appropriate empirical therapy than patients with cefotaxime-susceptible EK bacteraemia (81% vs. 97%, p<0.001) and died within 30 days (21% vs. 5%, p=0.001). Using the current breakpoints of the Clinical and Laboratory Standards Institute (CLSI) or the European Committee on Antimicrobial Susceptibility Testing (EUCAST), cefotaxime alone can identify ESBL or pAmpC producers. CTXNS-EK is an important and increasingly prevalent bacteraemia pathogen.
Department of Clinical Laboratory Medicine, Kyoto University Graduate School of Medicine, 54 Shogoin-Kawahara-cho, Sakyo-ku, Kyoto, 606-8507, Japan. yazblood@kuhp.kyoto-u.ac.jp
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Y
Matsumura
M
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Yamamoto
A
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Matsushima
M
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Nagao
Y
Y
Ito
S
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Takakura
S
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Ichiyama
D000368:Aged; D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D016470:Bacteremia / Q000382:microbiology / Q000473:pathology*; D002439:Cefotaxime / Q000494:pharmacology*; D015331:Cohort Studies; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D004927:Escherichia coli Infections / Q000382:microbiology / Q000473:pathology*; D005260:Female; D006785:Hospitals, University; D006801:Humans; D007564:Japan; D007710:Klebsiella Infections / Q000382:microbiology / Q000473:pathology*; D007711:Klebsiella pneumoniae / Q000187:drug effects* / Q000201:enzymology / Q000302:isolation & purification; D008297:Male; D008826:Microbial Sensitivity Tests / Q000379:methods; D008875:Middle Aged; D016133:Polymerase Chain Reaction; D012189:Retrospective Studies; D012307:Risk Factors; D012680:Sensitivity and Specificity; D016896:Treatment Outcome; D001618:beta-Lactamases / Q000032:analysis
D000900:Anti-Bacterial Agents; D004269:DNA, Bacterial; D001618:beta-Lactamases; D002439:Cefotaxime