Transcript Diapositive 1 - Medica-Tec

Evaluation of the FUNGIFAST® AFG yeast antifungal susceptibility test :
comparison with EUCAST and the E-Test method
INTERNAL STUDY - (ELITECH GROUP - INTERNATIONAL MICROBIO - SIGNES)
OBJECTIVES
FUNGIFAST® AFG (INTERNATIONAL MICROBIO), a commercial tray based on a microdilution method, allows the susceptibility testing of 5
antifungals: amphotericin B (AB), flucytosine (5 FC), fluconazole (FCZ), itraconazole (ITZ) and voriconazole (VRZ).
The aim of this internal study is to evaluate the tray in comparison with the reference method of EUCAST on 56 yeast clinical isolates and in
comparaison with the commercial E-Test method (AB Biodisk) on 100 yeast clinical isolates (10 species).
MATERIEL AND METHODS
Testing was performed on a sample of yeasts isolates (n=56 or 100) and 3 ATCC collection strains (Candida albicans 90029, C. glabrata
90030 and Cryptococcus neoformans 32045).
Species :
Candida albicans, Candida glabrata, Candida parapsilosis, Candida tropicalis , Candida lusitaniae, Candida krusei, Candida kefyr, Candida
guilliermondii, Saccharomyces cerevisiae, Cryptococcus neoformans.
The strains were provided by hospitals or private laboratories.
Each strain was subcultured for 24h in SABOURAUD medium and tested in parallel with E-Test (RPMI agar) for amphotericin B, flucytosine,
itraconazole, fluconazole and voriconazole and EUCAST broth micro dilution method for flucytosine, itraconazole, fluconazole and
voriconazole .
For EUCAST, MICs 50% were read spectrophotometrically after 24h (or 48h). For Etest, MICS were read after 24 h (or 48h)
For FUNGIFAST® AFG, 10mL of inoculated suspension medium (2McF) was added to the MES FUNGI medium, and 100mL was inoculated
in each well. Colorimetric reading was performed at 24h (or 48h) with a change in the growth indicator from dark violet to pink or colourless.
GROWTH
Fungifast® AFG tray
NO
GROWTH
Reading criteria
RESULTS
FUNGIFAST® AFG did not demonstrate a lack of growth, and 93% of the MIC values were obtained after 24h. The MIC values
of the QC strains showed good agreement and were within the reported limits.
The percentage of category agreement between FUNGIFAST® AFG vs. reference methods are given in the table 3
AB
5-FC
ITZ
FCZ
VRZ
nb. of strains
ND
n = 56
n = 56
n = 56
n = 56
EUCAST
ND
92.9%
69.6%
73.2%
92.9%
nb. of strains
n = 100
n = 99
n = 99
n = 99
n = 100
Etest
99%
90.9%
79.8%
84.8%
97%
overall rate
of agreement
(%)
82.2%
90.3%
Table 3 : % of category agreement of
Fungifast® AFG tray vs reference methods
CONCLUSION
 FUNGIFAST® AFG test is simple to perform and the colorimetric reading is less subjective than that of the reference method.
With an overall rate of agreement of 82.2% versus EUCAST and 90.3% versus Etest, the FUNGIFAST ® AFG test can be recommended as
an other method for the routine antifungal susceptibility testing of yeast clinical isolates.
 This test is a rapid, easy-to-use, easy-to-read and suitable for all clinical laboratories.
REFERENCES
Subcommitee of Antifungal Testing of the European Commitee on Antibiotic Sucseptibility Testing of the European Society of Clinical Microbiology and
Infectious Diseases. 2002. Method for the determination of Minimum Inhibitory Concentration (MIC) by Broth Dilution of Fermentative Yeasts. EUCAST
Discussion document E. Dis. 7.1 ESCMID.
REX J.H. et al. Antifungal susceptibility testing: pratical aspects and current challenges. Clin. Microbiol. Rev. 2001,14:643-658.