Consequences of switching from a fixed 2:1 ratio of amoxicillin/clavulanate (CLSI) to a fixed concentration of clavulanate (EUCAST) for susceptibility testing of Escherichia coli

被引:18
作者
Leverstein-van Hall, Maurine A. [1 ,2 ,3 ]
Waar, Karola [4 ]
Muilwijk, Jan [1 ]
Stuart, James Cohen [5 ,6 ]
机构
[1] Natl Inst Publ Hlth & Environm RIVM, Ctr Infect Dis Control CIb, Bilthoven, Netherlands
[2] Bronovo Hosp, Dept Med Microbiol & Infect Control, NL-2597 AX The Hague, Netherlands
[3] Diaconessenhuis, Leiden, Netherlands
[4] Izore, Ctr Infect Dis Friesland, Leeuwarden, Netherlands
[5] Reg Publ Hlth Lab, Haarlem, Netherlands
[6] Med Ctr Alkmaar, Dept Microbiol, Alkmaar, Netherlands
关键词
clinical outcomes; surveillance; Etest; discs; broth microdilution; CLINICAL BREAKPOINT CHANGES; ANTIMICROBIAL RESISTANCE;
D O I
10.1093/jac/dkt218
中图分类号
R51 [传染病];
学科分类号
100401 ;
摘要
Objectives: The CLSI recommends a fixed 2: 1 ratio of co-amoxiclav for broth microdilution susceptibility testing of Enterobacteriaceae, while EUCAST recommends a fixed 2 mg/L clavulanate concentration. The aims of this study were: (i) to determine the influence of a switch from CLSI to EUCAST methodology on Escherichia coli susceptibility rates; (ii) to compare susceptibility results obtained using EUCAST-compliant microdilution with those from disc diffusion and the Etest; and (iii) to evaluate the clinical outcome of patients with E. coli sepsis treated with co-amoxiclav in relation to the susceptibility results obtained using either method. Methods: Resistance rates were determined in three laboratories that switched from CLSI to EUCAST cards with the Phoenix system (Becton Dickinson) as well as in 17 laboratories that continued to use CLSI cards with the VITEK 2 system (bioMerieux). In one laboratory, isolates were simultaneously tested by both the Phoenix system and either disc diffusion (n = 471) or the Etest (n = 113). Medical and laboratory records were reviewed for E. coli sepsis patients treated with co-amoxiclav monotherapy. Results: Only laboratories that switched methodology showed an increase in resistance rates - from 19% in 2010 to 31% in 2011 (P<0.0001). All isolates that tested susceptible by microdilution were also susceptible by disc diffusion or the Etest, but of 326 isolates that tested resistant by microdilution, 43% and 59% tested susceptible by disc diffusion and the Etest, respectively. Among the 89 patients included there was a better correlation between clinical response and measured MICs using the Phoenix system than the Etest. Conclusions: EUCAST methodology resulted in higher co-amoxiclav E. coli resistance rates than CLSI methodology, but correlated better with clinical outcome. EUCAST-compliant microdilution and disc diffusion provided discrepant results.
引用
收藏
页码:2636 / 2640
页数:5
相关论文
共 14 条
  • [1] Albert X, 2004, Cochrane Database Syst Rev, pCD001209, DOI 10.1002/14651858.CD001209.pub2
  • [2] [Anonymous], 2010, CLSI Document M100-S20
  • [3] CLSI, 2011, M100S21 CLSI
  • [4] [European Committee on Antimicrobial Susceptibility Testing [EUCAST] European Committee on Antimicrobial Susceptibility Testing], 2011, BREAKP TABL INT MICS
  • [5] Assessment of the Phoenix™ automated system and EUCAST breakpoints for antimicrobial susceptibility testing against isolates expressing clinically relevant resistance mechanisms
    Giani, T.
    Morosini, M. I.
    D'Andrea, M. M.
    Garcia-Castillo, M.
    Rossolini, G. M.
    Canton, R.
    [J]. CLINICAL MICROBIOLOGY AND INFECTION, 2012, 18 (11) : E452 - E458
  • [6] Fixed or variable concentrations of beta-lactamase inhibitors in in-vitro tests?
    Greenwood, D
    [J]. JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY, 1996, 38 (01) : 17 - 20
  • [7] Increasing antimicrobial resistance and the management of uncomplicated community-acquired urinary tract infections
    Gupta, K
    Hooton, TM
    Stamm, WE
    [J]. ANNALS OF INTERNAL MEDICINE, 2001, 135 (01) : 41 - 50
  • [8] Hobby T, 2011, 21 EUR C CLIN MICR I
  • [9] Effects of clinical breakpoint changes in CLSI guidelines 2010/2011 and EUCAST guidelines 2011 on antibiotic susceptibility test reporting of Gram-negative bacilli
    Hombach, Michael
    Bloemberg, Guido V.
    Boettger, Erik C.
    [J]. JOURNAL OF ANTIMICROBIAL CHEMOTHERAPY, 2012, 67 (03) : 622 - 632
  • [10] Kazmierczak A, 2005, ANTIMICROBIAL AGENTS: ANTIBACTERIALS AND ANTIFUNGALS, P401