R2737 Abstract (publication only) Corynebacterium spp. and Arcanobacterium haemolyticum identification. Usefulness of the Vitek 2 ANC card R. Soloaga*, N. Carrion, C. Barberis, M. Almuzara, L. Guelfand, J. Pidone, C. Vay (Buenos Aires, AR)

Introduction: Corynebacterium diphtheriae and C.ulcerans may be isolated from suspected cases of classical diphtheria, cutaneous diphtheria and very rarely from other clinical infections. Non-diphtheric corynebacteria are opportunistic pathogens, especially in nosocomial setting where they have been associated with endocarditis, pulmonary infection, medical devices infections and urinary tract infection. A. haemolyticum infection manifests as exudative pharyngitis and tonsillitis accompanied by cervical lymphadenopathy and less commonly, the organism causes deep-seated infections and skin and soft-tissue infections Objective: The aim of this study was to determine the Vitek 2 ANC card (bioMèrieux, Marcy l’Etoile, France) performance for identification of the most frequently clinical relevant Corynebacterium species and Arcanobacterium haemolyticum Methods: Sixty-two unique clinical isolates (2 C. diphtheriae, 7 C. jeikeium, 10 C. amycolatum, 15 C.striatum, 12 C.urealyticum, 1 C.minutissimum, 8 C. pseudodiphtheriticum, 1 C. ulcerans and 6 Arcanobacterium haemolyticum) represented the 9 taxa included in the Vitek 2 ANC database and 6 strains represented related species not included in the database were analyzed in this study. All the strains were identified using 16S rRNA gene sequencing (16S) as the reference method. For Vitek identification, all the strains were isolated in pure culture on Columbia blood agar. After 24-48 h incubation to 35ºC in ambient air, a bacterial suspension was made in 0.45% aqueous ClNa and adjusted to a McFarland of 2.7-3.2 with Vitekk 2 Densicheck instrument (bioMérieux).The inoculated card was loaded into the Vitek 2C automated identification system according to the manufacturer´s instruction. A computer-assisted algorithm was used to interpret the results. Results: The Vitek 2C ANC card correctly identified 60 (96.7%) of 62 isolates; only two strain (2.3%) remained unidentified. The results were available within 6.25 h. Identification of 6 non-data base strains resulted in 3 strains incorrectly identified as belonging to species in the data base. Conclusion: ANC card could be considered a reliable and useful tool for routine use in the rapid identification of the most frequent Corynebacterium species isolated in human infections.