A customer from (b)(6) notified biomerieux of a misidentification of (b)(6) as kingella denitrificans in association with the vitek® 2 nh test kit.
An investigation was performed.
The reference method (sequencing full 16s) was used to determine the intended result, and gave an excellent identification to the species (b)(6).
Vitek® 2 nh cards were tested from the customer lot (cl : 2450075203) and a random lot (rl : 2450061203).
Both lots gave an excellent identification to the species (b)(6).
The misidentification to kingella denitrificans was not duplicated.
A review of the customer's kingella denitrificans data against expected reactions for (b)(6) demonstrated 2 atypical (b)(6) reactions (arga and tyra) and 1 atypical (b)(6) reaction (ellm) according to the nh knowledge base, contributing to the misidentification.
An increased number of atypical results can indicate a strain with decreased viability, user set up error or an atypical strain.
The 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 out on the bench outside of co2 for extended periods, it will become less robust and therefore less reactive in the nh card.
The investigation concluded the vitek® 2 nh test kit performed as intended and no further action is required.
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