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EUCAST and CLSI: How to Assess in Vitro Susceptibility and Clinical Resistance

  • Advances in Diagnosis of Invasive Fungal Infections (U Binder and A Groll, Section Editors)
  • Published:
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Abstract

There are two different approved reference procedures based on microdilution techniques for antifungal susceptibility testing (AFST) of fungal species, the CLSI and the EUCAST procedures. Although there have always been some methodological differences between them, AFST results are comparable. In addition, current breakpoints values of antifungal compounds to interpret AFST results set by both institutions are very similar with some exceptions. Experts advised AFST should be done with validated commercial techniques for a routine daily practice and discrepant results should be confirmed by reference procedures particularly for isolates with borderline/resistant MIC values. Reference methods by EUCAST and CLSI should be also used in periodical epidemiological studies, to evaluate new antifungal agents, new methods of AFST and to know the susceptibility profile of rare and emerging fungal species.

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Disclosure

Dr. M. Cuenca-Estrella has received payment for consulting services, expert testimony, and lectures, as well as grant support from Astellas, Gilead, Pfizer, and MSD.

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Authors and Affiliations

  1. Mycology Reference Laboratory, National Center for Microbiology, Instituto de Salud Carlos III, Madrid, Spain

    Ana Alastruey-Izquierdo & Manuel Cuenca-Estrella

  2. Servicio de Micología, Centro Nacional de Microbiología, Instituto de Salud Carlos III, Ctra Majadahonda-Pozuelo Km 2. 28220, Majadahonda, Madrid, Spain

    Manuel Cuenca-Estrella

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  1. Ana Alastruey-Izquierdo
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Correspondence to Manuel Cuenca-Estrella.

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Alastruey-Izquierdo, A., Cuenca-Estrella, M. EUCAST and CLSI: How to Assess in Vitro Susceptibility and Clinical Resistance. Curr Fungal Infect Rep 6, 229–234 (2012). https://doi.org/10.1007/s12281-012-0100-3

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