Korean J Clin Microbiol.  2010 Sep;13(3):114-120. 10.5145/KJCM.2010.13.3.114.

Comparison of ATB FUNGUS 2 and VITEK-2 Antifungal Susceptibility (AST-YS01) Tests for Candida Species Isolated from Blood Culture

• Park SD
• Uh Y
• Jang IH
• Yoon KJ
• Shin JH

• KMID: 1461622
• DOI: http://doi.org/10.5145/KJCM.2010.13.3.114

Abstract

BACKGROUND
The VITEK-2 yeast susceptibility test (AST-YS01; bioMerieux, Hazelwood, MO, USA) has recently been introduced as a fully automated, commercial antifungal susceptibility test system that determines MIC endpoints spectrophotometrically, thereby eliminating subjective errors. We compared the ATB FUNGUS 2 (bioMerieux) and VITEK-2 (AST-YS01) systems to the CLSI M27 method for susceptibility testing of Candida isolates.
METHODS
We tested 59 Candida species that were isolated from blood cultures at Wonju Christian Hospital between September 2008 and August 2009. We compared MIC results for amphotericin B, flucytosine, fluconazole and voriconazole using the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests to those obtained by the CLSI M27 broth microdilution method.
RESULTS
Within two-fold dilutions of MICs, the agreement of the ATB FUNGUS 2 and VITEK-2 (AST-YS01) tests with the CLSI method according to antifungal agents were: amphotericin B, 100% vs. 100% flucytosine, 100% vs. 100% fluconazole, 83.6% vs. 98.3% and voriconazole, 83.6% vs. 96.7%, respectively. The categorical discrepancies for fluconazole and voriconazole were 20.4% and 18.6% for ATB FUNGUS 2, and 6.8% and 0% for VITEK-2 (ASTYS01). There were no major errors for fluconazole and voriconazole in either ATB FUNGUS 2 or VITEK-2 (AST-YS01) tests.
CONCLUSION
The VITEK-2 system (AST-YS01) appears to be rapid and highly correlative with the CLSI method, suggesting that it is effective for antifungal susceptibility testing for Candida species in clinical settings.

Keyword

Antifungal susceptibility; Blood culture; Candida species; VITEK-2; ATB FUNGUS 2; CLSI

MeSH Terms

Amphotericin B
Antifungal Agents
Candida
Fluconazole
Flucytosine
Fungi
Pyrimidines
Triazoles
Yeasts
Amphotericin B
Antifungal Agents
Fluconazole
Flucytosine
Pyrimidines
Triazoles

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