A customer reported a misidentification of neisseria meningitidis as neisseria gonorrhoeae by the vitek® 2 nh test kit lot # 245369522 with vitek 2 7.01 software.The identification to neisseria meningitidis was confirmed through pcr and ms.The customer did not submit strain or raw data for analysis.An investigation was conducted.The customer had set up the patient isolate from a 48-hour culture grown on chocolate agar.Use of a 48-hour culture is not recommended.The age of culture should be 18-24 hrs.A lab report was submitted that showed a very good identification of neisseria gonorrhoeae with five (5) atypical positive reactions (arga, lysa, tyra, pvate, appa), and one (1) atypical negative reaction (dmal), for an identification of neisseria meningitidis according to the vitek® 2 nh knowledge base.An increased number of atypical positive reactions can indicate contamination, mixed culture, use of non recommended media or other user set up errors or an atypical strain.However without the strain or raw data it's not possible to further evaluate the cause of the misidentification.A review of quality records confirmed the nh id lot 245369522 met qc criteria for initial performance testing and final release.In conclusion, the customer tested the isolate from 48-hour culture, rather than 18-24 hours as specified in the nh id product information.The customer did not submit the isolate or raw card data, therefore the misidentification could not be confirmed.
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