This report was initially submitted following notification that a customer in (b)(6) reported the occurrence of a misidentification of (b)(6) (atcc® 19424¿) as neisseria cinerea in association with the vitek® 2 nh identification test kit (card).The customer submitted the (b)(6) (atcc® 19424¿) sample for investigational testing.The investigation included testing of three (3) nh id card lots with the customer strain and the internal biomérieux strain: customer lot 245390220 (cl1) tested twice on both strains.Customer lot 2450185403 (cl2) tested twice on both strains.Random lot 245398920 (rl) tested twice on both strains.Isolates were subcultured as indicated in the package insert.The internal strain (all card lots) obtained identification to (b)(6).The customer strain (all card lots) obtained identification to (b)(6).The investigation did not reproduce the customer results for the customer strain nor the internal reference strain whatever the lot tested.After comparison of biochemical profiles between expected results and the profile obtained by the customer (identification to neisseria cinerea), the investigation observed two (2) discrepant tests (false negative arga and appa).An increased number of atypical negative results can indicate a strain with decreased viability, user set up error or an atypical strain.An increased number of atypical negative reactions may have been caused by leaving the isolate out of co2 for an extended period of time.Since (b)(6) is a fastidious species, it needs to be contained in a co2 environment to retain robustness.If this species is left outside of co2 for extended periods, it will become less robust and therefore less reactive in the nh id card.The investigation concluded the vitek® 2 nh id card is performing as intended.
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