Multicenter evaluation of the updated and extended API (RAPID) Coryne database 2.0

Abstract

In a multicenter study, 407 strains of coryneform bacteria were tested with the updated and extended API (RAPID) Coryne system with database 2.0 (bioMérieux, La-Balme-les-Grottes, France) in order to evaluate the system's capability of identifying these bacteria. The design of the system was exactly the same as for the previous API (RAPID) Coryne strip with database 1.0, i.e., the 20 biochemical reactions covered were identical, but database 2.0 included both more taxa and additional differential tests. Three hundred ninety strains tested belonged to the 49 taxa covered by database 2.0, and 17 strains belonged to taxa not covered. Overall, the system correctly identified 90.5% of the strains belonging to taxa included, with additional tests needed for correct identification for 55.1% of all strains tested. Only 5.6% of all strains were not identified, and 3.8% were misidentified. Identification problems were observed in particular for Corynebacterium coyleae, Propionibacterium acnes, and Aureobacterium spp. The numerical profiles and corresponding identification results for the taxa not covered by the new database 2.0 were also given. In comparison to the results from published previous evaluations of the API (RAPID) Coryne database 1.0, more additional tests had to be performed with version 2.0 in order to completely identify the strains. This was the result of current changes in taxonomy and to provide for organisms described since the appearance of version 1.0. We conclude that the new API (RAPID) Coryne system 2.0 is a useful tool for identifying the diverse group of coryneform bacteria encountered in the routine clinical laboratory.

Identification of the emerging skin pathogenCorynebacterium amycolatumusing PCR-amplification of the essentialdivIVAgene as a target

“…Infections by Corynebacterium species are conventionally diagnosed by culturing, followed by phenotypic analysis of the isolates (API Coryne strips, BioMérieux) (Funke et al, 1997a). However, the reliability of the identification of Corynebacterium isolates by their phenotype is limited and in some cases only 25-30% of the samples were correctly identified (Roux et al, 2004).…”

Identification of Corynebacterium amycolatum and Other Nonlipophilic Fermentative Corynebacteria of Human Origin

“…Many conventional tests have variable results with this species, leading to confusion with other fermentative corynebacteria, such as C. striatum or C. minutissimum and, more particularly, C. xerosis (3,13). Moreover, C. amycolatum was not included in some commercial identification systems, resulting in no identification or misidentification of the strains (1,13), although it now appears in the updated API Coryne database 2.0 (5). Recently, several new nonlipophilic fermentative corynebacteria, isolated from humans, have been described: C. argentoratense (12), C. coyleae (4), and C. imitans (2).…”

Evaluation of the RapID CB Plus System for Identification of Coryneform Bacteria andListeriaspp

“…Difficulties with the identification of Listeria spp. on the species level only with commercial identification systems but not by other conventional tests have been reported before (4,6).…”