Browse by author
Lookup NU author(s): Katherine Gould
This work is licensed under a Creative Commons Attribution-NonCommercial 4.0 International License (CC BY-NC 4.0).
© The Author 2016. Objectives: To compare the concordance of ceftaroline MIC values by reference broth microdilution (BMD) and Etest (bioMérieux, France) for MSSA and MRSA isolates obtained from PREMIUM (D372SL00001), a European multicentre study. Methods: Ceftaroline MICs were determined by reference BMD and by Etest for 1242 MSSA and MRSA isolates collected between February and May 2012 from adult patients with community-acquired pneumonia or complicated skin and soft tissue infections; tests were performed across six European laboratories. Selected isolates with ceftaroline resistance in broth (MIC >1 mg/L) were retested in three central laboratories to confirm their behaviour. Results: Overall concordance between BMD and Etest was good, with >97% essential agreement and >95% categorical agreement. Nevertheless, 12 of the 26 MRSA isolates found resistant by BMD scored as susceptible by Etest, with MICs ≤1 mg/L, thus counting as very major errors, whereas only 5 of 380 MRSA isolates found ceftaroline susceptible in BMD were miscategorized as resistant by Etest. Twenty-one of the 26 isolates with MICs of 2 mg/L by BMD were then retested twice by each of three central laboratories: BMD MICs of 2 mg/L were consistently found for 19 of the 21 isolates. Among 147 Etest results for these 21 isolates (original plus six repeats per isolate) 112 were >1 mg/L. Conclusions: BMD and Etest have good overall agreement for ceftaroline against Staphylococcus aureus; nevertheless, reliable Etest-based discrimination of the minority of ceftaroline-resistant (MIC 2 mg/L) MRSA is extremely challenging, requiring careful reading of strips, ideally with duplicate testing.
Author(s): Canton R, Livermore DM, Morosini MI, Diaz-Reganon J, Rossolini GM, on behalf of the PREMIUM Study Group
Publication type: Article
Publication status: Published
Journal: Journal of Antimicrobial Chemotherapy
Year: 2017
Volume: 72
Issue: 2
Pages: 431-436
Print publication date: 01/02/2017
Online publication date: 20/10/2016
Acceptance date: 20/09/2016
Date deposited: 30/05/2017
ISSN (print): 0305-7453
ISSN (electronic): 1460-2091
Publisher: Oxford University Press
URL: https://doi.org/10.1093/jac/dkw442
DOI: 10.1093/jac/dkw442
Notes: Kate Gould = member of the PREMIUM Study Group
Altmetrics provided by Altmetric
