Open AccessReliability of the WIDERYST Susceptibility Testing System for Detection of In Vitro Antifungal Resistance in Yeasts
Author(s) -
Manuel CuencaEstrella,
Alicia GómezLópez,
M. Olga Gutiérrez,
María José Buitrago,
Juan Luis Rodríguez-Tudela
Publication year - 2008
Publication title -
antimicrobial agents and chemotherapy
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 2.07
H-Index - 259
eISSN - 1070-6283
pISSN - 0066-4804
DOI - 10.1128/aac.01016-07
Subject(s) - broth microdilution , fluconazole , cryptococcus neoformans , biology , microbiology and biotechnology , amphotericin b , antifungal , minimum inhibitory concentration , antimicrobial
This study evaluated the WIDERYST system, a commercially available computer-assisted image-processing device for the antifungal susceptibility testing of yeasts. A collection of 90 clinical isolates selected to represent ranges of susceptibilities in vitro as broad as possible was tested. An evaluation compared the results obtained by the new system with those achieved by both the Clinical and Laboratory Standards Institute (CLSI) microdilution reference procedure and the antifungal susceptibility standard of the European Committee for Antimicrobial Susceptibility Testing (EUCAST). Overall, the agreement and the correlation index between results obtained by the EUCAST method and the WIDERYST system were 89% and 0.84 (P < 0.01), respectively, and agreement and correlation index between data obtained by the CLSI procedure and the WIDERYST system were 90% and 0.86 (P < 0.01), respectively. The system was able to detect amphotericin B-resistant isolates. AllCandida sp. isolates with resistance in vitro to azole agents were detected as well. The system misclassified some isolates belonging to the slowly growing generaDipodascus andPichia . A total of 2.7% very major errors were detected for fluconazole. The WIDERYST system is an alternative to reference procedures for antifungal susceptibility testing of clinical isolates of yeasts, particularly forCandida andCryptococcus species.