This report was initially submitted in response to a customer in (b)(6) reporting the occurrence of false susceptible fluconazole results for a candida norvegensis eeq strain in association with the vitek® 2 ast-ys08 test kit (ref 420739).An internal biomérieux investigation was performed that included testing for both fluconazole (flu) and flucytosine (fct) results with a strain of candida norvegensis on vitek® 2 ast-ys08 cards.This strain is from a biologie prospective survey (mycology 2017- sample 3a).Id testing : identification was confirmed to candida norvegensis on vitek 2 yst id card (lot 2430356103).Ast testing: · reference method to determine the intended result for fluconazole and flucytosine: broth microdilution, method used to develop the formularies "flu02n" / "fct02n" (in ast-ys08 card).· flu mic = 16 mg/l intermediate · fct mic = 8 mg/l intermediate interpretation according to vitek 2 breakpoints in v7.01 : fda 2009 breakpoints for candida / fluconazole s =8 - i 16-32 - r >/=64.Fda 2012 breakpoints for candida / flucytosine : s =4 - i 8-16 - r >/=32.Note: for antifungals, essential agreement between vitek® 2 card and reference method mics is +/- 2 doubling dilutions.· products & system incriminated: -ast -ys08 on vitek 2 v7.01 three (3) vitek 2 ast-ys08 lots were tested from sabouraud dextrose agar (sda).Vitek 2 gave the following results on the three (3) lots tested: **flu mic = 8 mg/l susceptible **fct mic = 4 mg/l susceptible the vitek 2 results are within essential agreement with the reference mic within +/- 1 doubling dilution.Conclusion: -the customer results were duplicated on the ast-ys08 cards (mic flu= 8 mg/l s and fct mic=4 mg/l s).-the vitek 2 ast-ys08 cards perform as intended.The vitek 2 values are within essential agreement with the reference results obtained in bmd.-the reference mic for both fluconazole and flucytosine are in the middle of the breakpoints, so the strain can be susceptible or resistant within +/- 2 doubling dilutions.-->borderline strain.
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