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EUCAST and CLSI: Working Together Towards a Harmonized Method for Antifungal Susceptibility Testing

  • Current Management of Fungal Infections (L Ostrosky-Zeichner, Section Editor)
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Abstract

The U.S. Clinical and Laboratory Standards Institute (CLSI) and the European Committee of Antimicrobial Susceptibility Testing (AFST-EUCAST) have developed broth microdilution methodologies for testing yeasts and filamentous fungi (molds). The mission of these methodologies is to identify in vitro antifungal resistance, which is accomplished by the use of either clinical breakpoints (CBPs), or to a lesser degree, epidemiologic cutoff values (ECVs). The newly adjusted and species-specific CLSI CBPs for Candida spp. versus fluconazole and voriconazole have ameliorated some of the differences between the two methodologies. In the absence of CBPs for mold testing, CLSI ECVs are available for six Aspergillus species versus the triazoles, caspofungin and amphotericin B. Recently, breakpoints were developed by the EUCAST for certain Aspergillus spp. versus amphotercin B, itraconazole and posaconazole, which to some extent are comparable to ECVs. We summarize these latest accomplishments, which have made possible the harmonization of some susceptibility cutoffs, if not methodologies for some agent/species combinations.

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Papers of particular interest, published recently, have been highlighted as: • Of importance

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Disclosure

A. Espinel-Ingroff: grants from Astellas and MICOMOLSL, received payment for contribution to the Journal of Invasive Fungal Infections; M. Cuenca-Estrella: has received grants and payment for consultancy, expert testimony, and lectures from Astellas, Pfizer, Gilead, and MSD; E. Cantón: none

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Authors and Affiliations

  1. VCU Medical Center, 3804 Dover Rd., Richmond, VA, 23221, USA

    Ana Espinel-Ingroff

  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

  3. Unidad Microbiología Experimental, Centro de Investigación, Hospital Universitario y Politécnico La Fe, Avenida Campanar, 21, 46009, Valencia, Spain

    Emilia Cantón

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  1. Ana Espinel-Ingroff
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Correspondence to Ana Espinel-Ingroff.

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Espinel-Ingroff, A., Cuenca-Estrella, M. & Cantón, E. EUCAST and CLSI: Working Together Towards a Harmonized Method for Antifungal Susceptibility Testing. Curr Fungal Infect Rep 7, 59–67 (2013). https://doi.org/10.1007/s12281-012-0125-7

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