Journal List > Korean J Clin Microbiol > v.13(3) > 1038189

Korean J Clin Microbiol. 2010 Sep;13(3):114-120. Korean.
Published online September 30, 2010.  https://doi.org/10.5145/KJCM.2010.13.3.114
Copyright © 2010 The Korean Society of Clinical Microbiology
Comparison of ATB FUNGUS 2 and VITEK-2 Antifungal Susceptibility (AST-YS01) Tests for Candida Species Isolated from Blood Culture
Soon Deok Park,1 Young Uh,1 In Ho Jang,1 Kap Jun Yoon,1 and Jong Hee Shin2
1Department of Laboratory Medicine, Yonsei University Wonju College of Medicine, Wonju, Korea.
2Department of Laboratory Medicine, Chonnam National University Medical School, Gwangju, Korea.

Correspondence: Young Uh, Department of Laboratory Medicine, Wonju Christian Hospital, 162 Ilsan-dong, Wonju 220-701, Korea. (Tel) 82-33-741-1592, (Fax) 82-33-731-0506, Email: u931018@yonsei.ac.kr
Received January 22, 2010; Revised April 30, 2010; Accepted June 18, 2010.

Abstract

Background

The VITEK-2 yeast susceptibility test (AST-YS01; bioMérieux, 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 (bioMérieux) 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.

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

Tables


Table 1
In vitro susceptibilities of 59 isolates of Candida spp. to amphotericin B, flucytosine, fluconazole and voriconazole as determined with the ATB FUNGUS 2 and VITEK-2 (AST-YS01) system, and by CLSI M27 BMD methods
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Table 2
Categorical agreement of flucytosine, fluconazole and voriconazole MICs determined by two commercial antifungal tests and CLSI M27 BMD method for 59 isolates of Candida spp.
Click for larger image

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