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An internal biomérieux investigation was initiated due to false results associated with the vitek® 2 ast-gn70 card when testing api survey strain ur-06 escherichia coli.Ampicillin/sulbactam (ams) and cefepime (fep) were reported as susceptible.The expected result for these drugs was resistant.The strain was submitted for investigation.The submitted strain was subcultured, and the identification was confirmed as e.Coli.Testing was performed on vitek 2 ast-gn70 cards from the customer lots (5900727403, 5900755403) and a random lot (5900650403), as well as agar dilution (ad) as the reference method for fep02n and sam01n formulations found on this card.Clsi breakpoints: ams = 8 (s) 16 (i) >/= 32 (r) fep = 2 (s) 4-8 (sdd) >/=16 (r) ampicillin/sulbactam mics = 8 (s), 4 (s), >/=32 (r) on the three(3) vitek 2 gn70 cards tested.Ams ad mic =32 (r).Cards and reference method are in agreement for one (1) card, and essential agreement error for the other two (2) cards, demonstrating a very major error for the vitek 2.Cefepime mics =1* on two cards mic = 2* on the remaining card, all with aes software modification to resistant due to a proposed esbl phenotype.Fep ad mic = 8, demonstrating as essential agreement error between vitek 2 and reference method.Conclusion: atypical survey strain a complaint and quality review was performed, which did not identify this discrepancy as a systemic quality issue.
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