Evaluation of the Vitek 2 ANC Card for Identification of Clinical Isolates of Anaerobic Bacteria

Abstract

An evaluation of the Vitek 2 ANC card (bioMérieux, Marcy l'Etoile, France) was performed with 301 anaerobic isolates. Each strain was identified by 16S rRNA gene sequencing, which is considered to be the reference method. The Vitek 2 ANC card correctly identified 239 (79.4%) of the 301 clinical isolates to the genus level, including 100 species that were not represented in the database. Correct species identification was obtained for 60.1% (181/301) of the clinical isolates. For the isolates not identified to the species level, a correct genus identification was obtained for 47.0% of them (47/100), and 16 were accurately designated not identified. Although the Vitek 2 ANC card allows the rapid and acceptable identification of the most common clinically important anaerobic bacteria within 6 h, improvement is required for the identification of members of the genera Fusobacterium, Prevotella, and Actinomyces and certain Gram-positive anaerobic cocci (GPAC).The involvement of anaerobes in numerous and severe clinical infections has been reported (5, 13). The differences in antimicrobial susceptibility (9, 16) and the development of resistance to antimicrobial drugs (16) among anaerobic bacteria have been documented. Traditional methods for the identification of anaerobic pathogens are not always available in clinical bacteriology laboratories and are often laborious and time-consuming (12). Therefore, the need for a rapid and accurate method for the identification of anaerobic pathogens is highly desirable for appropriate treatment.In the last decades, different commercial enzyme kits for the identification of clinically relevant anaerobe isolates have been developed and evaluated, e.g., the RapID-ANA II panel, the Minitek systems, the Vitek ANI card, the BBL Crystal ANR ID kit, the API rapid ID 32 A system, and the API 20 A system (6-8, 10, 14, 18, 19).The new Vitek 2 ANC card (bioMérieux, Marcy l'Etoile, France) is designed to provide clinical laboratories with the capability for the rapid and accurate identification of clinically relevant anaerobic bacteria and Corynebacterium species. The card contains 64 microwells with 36 colorimetric enzymatic tests. The ANC database comprises 63 taxa of anaerobic bacteria and corynebacteria. Twenty genera are listed in the Vitek 2 ANC database: Actinomyces, Arcanobacterium, Bacteroides (Parabacteroides), Bifidobacterium, Clostridium, Collinsella, Corynebacterium, Eggerthella, Eubacterium, Finegoldia, Fusobacterium, Lactobacillus, Microbacterium, Parvimonas (formerly Micromonas), Peptoniphilus, Peptostreptococcus, Prevotella, Propionibacterium, Staphylococcus, and Veillonella. The system provides only a genus-level identification for Bifidobacterium sp. and Veillonella sp. Of the 36 biochemical profiles, 13 are fermentation tests, 17 are glycosidase and arylamidase tests, 2 are alkaline reactions, and 4 are other biochemical tests. Additional simple off-line tests, including cell morphology, Gram stain characteristic, and aerotolerance testing, are required to complete the i...

Species Identification of Clinical Isolates of Anaerobic Bacteria: a Comparison of Two Matrix-Assisted Laser Desorption Ionization–Time of Flight Mass Spectrometry Systems

“…The overall performance of the Shimadzu/SARAMIS system was better with the ␣-cyano matrix than with the DHB matrix. The performance of the MALDI-TOF MS systems for species identification is faster and less expensive than those of the commercial phenotypic systems like the Rapid ID 32A or Vitek 2 ANC card (bioMérieux, Marcy l'Etoile, France) (7,11). Although a higher number of species can be identified with 16S rRNA gene sequencing, it is resource saving to use the MALDI-TOF MS system as a first-line identification system and to reserve gene sequencing for isolates that cannot be identified to the species level by MALDI-TOF MS (8).…”

Treatment of cutaneous actinomycosis with amoxicillin/clavulanic acid

“…Diagnosis was based on clinical and microbiological criteria (presence of granules on direct examination (KOH 10%) and/or Giemsa stains, as isolation of the agent on thioglycollate broth and blood agar with 5% CO 2 atmosphere). Identification of isolated strains was completed using the automated system Vitek 2ANC-Card (Biomerux V R , Marcy-l' Etoile, France) (15).…”

Bacteremia Caused byEggerthella lentain an Elderly Patient with an Intra-abdominal Abscess

“…lenta is an anaerobic, non-spore-forming, gram-positive bacillus of the Coriobacteriaceae first described in 1935 by Eggerth and API 20A systems (bioMérieux) [9][10][11]. 16S rRNA sequencing is useful for confirming an E. lenta infection and is considered to be the gold standard [12].…”