Microbiological evaluation of the new VITEK 2 Neisseria-Haemophilus identification card

Abstract

VITEK 2 is an automated identification system for diverse bacterial and fungal species. A new card (the Neisseria-Haemophilus [NH] card) for the identification of Neisseria spp., Haemophilus spp., and other fastidious gram-negative or gram-variable microorganisms has been developed, but its performance in a routine clinical laboratory has not yet been evaluated. In this study, a total of 188 bacterial strains belonging to the genera Actinobacillus, Campylobacter, Capnocytophaga, Cardiobacterium, Eikenella, Gardnerella, Haemophilus, Kingella, Moraxella, and Neisseria were investigated. The NH card was able to identify 171 strains (91%) correctly without the need for extra tests; one strain (0.5%) was misidentified, and five strains (2.7%) could not be classified. Eleven strains (5.8%) were identified with a low level of discrimination, and simple additional tests were required to increase the correct-identification rate to 96.8%. The results were available within 6 h. Based on these results, the new VITEK 2 NH card appears to be a good method for the identification of diverse groups of fastidious organisms, which would otherwise require testing with multiple systems. However, more work is needed to evaluate the performance of VITEK 2 with regard to Haemophilus, Actinobacillus, Cardiobacterium, Eikenella, and Kingella bacteria because of the insufficient number of strains tested in this study. Moreover, further reduction of the detection time would be desirable.