A customer in (b)(6) notified biomérieux of misidentification of a neisseria species in association with vitek® 2 nh card.Customer states that they took one colony from a thayer martin dish and one from a chocolate agar dish for the same patient, prepared two suspensions, and ran two tests simultaneously with two vitek® 2 nh cards.They have received two different results: 90% probability neisseria meningitidis and 94% probability neisseria cinerea.The physician suspected that the colony was neisseria gonorrhoeae.Therefore, they also performed additional pcr test and obtained a result of neisseria gonorrhoeae.Customer states they no longer have the isolate to retest.There is no indication or report from the laboratory that the discrepant result led to any adverse event related to the patient's state of health.A biomérieux internal investigation will be initiated.
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A customer in armenia notified biomérieux of a misidentification of a neisseria species in association with vitek® 2 nh card.The customer stated that they ran two tests simultaneously with two vitek® 2 nh cards.They received 2 different results: 90% probability neisseria meningitidis and 94% probability neisseria cinerea.A pcr test obtained a result of neisseria gonorrhoeae.An internal biomérieux investigation was performed.The customer reported plating a sample from the same patient to chocolate agar and thayer martin.Plates were incubated in a microaerophilic environment.Originally it was reported that the nh cards were set up from cultures incubated at 48 hours, but it was later changed to 24 hour age of culture by the customer.One (1) colony from each agar type was used to prepare two (2) suspensions, which were each inoculated into an nh card.Each card provided a different identification, which were both incorrect.One (1) lab report showed a good identification of n.Meningitidis with seven (7) atypical reactions (5 negative: phea, proa, tyra, appa, dglu and 2 positive: ggt & phc) for an identification of n.Gonorrhoeae according to the nh knowledge base.The second lab report showed a very good identification of n.Cinerea with five (5) atypical negative reactions (phea, proa, tyra, appa, dglu) for an identification of n.Gonorrhoeae according to the nh knowledge base.Review of customer's integrated raw data shows no growth in these wells when compared to other strains of neisseria gonorrohoeae; strong positive reactions should occur.An increased number of atypical negative results can indicate a strain with decreased viability, user set up error, or an atypical strain.Based on the information from the customer, it is possible that misidentifications may be due to set up errors, which could have increased the number of atypical negative reactions.Use of a microaerophilic environment rather than co2 could compromise viability of the organism.In addition, using one (1) colony to make a mcfarland density of 2.7 - 3.3 would be difficult and would most likely result in a suspension of much lower density.This could also cause an increase in atypical negative reactions.Without the strain it's not possible to further evaluate the cause of the misidentification.Vitek 2 nh lot# 2450267403 met final qc release criteria.There were no issues observed on the initial qc performance testing.
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