Evaluation of the repliscan system for Enterobacteriaceae identification

A total of 1,013 isolates of Enterobacteriaceae were identified in parallel by the Repliscan (Cathra International, Ontario, Canada) and API 20E (Analytab Products, Plainview, N.Y.) systems. There was a 62% agreement at the genus level between the two systems. Of the 38% discrepant results, Repliscan classified 22% as "biochemical pattern not on file," 8% as a multiple-genus group which included the API 20E identification, and 8% as a genus other than that designated by API 20E. Relative to the various genera, Repliscan agreed with API 20E as follows: Escherichia coli, 80%; Klebsiella spp., 76%; Citrobacter spp., 75%; Proteus spp., 69%; Providencia spp., 54%; Serratia spp., 49%; Enterobacter spp., 25%; Shigella spp., 4%; and Salmonella spp., 0%. Repliscan identified 35% of Enterobacter spp. isolates as Citrobacter spp., 91% of Shigella spp. isolates as a multiple-choice-genus group, and 67% of Salmonella spp. isolates as "biochemical pattern not on file." Repliscan agreed with API 20E at the species level as follows: E. coli, 80%; Klebsiella spp., 56%; Citrobacter spp., 66%; Proteus spp., 55%; Providencia spp., 46%; Serratia spp., 39%; Enterobacter spp., 18%; Shigella spp., 4%; and Salmonella spp., 0%. These findings indicate that the Repliscan system in its present stage of development does not reliably identify the Enterobacteriaceae.