Evaluation of the Repliscan II System for identification of Enterobacteriaceae

In a precious report (Woolfrey et al., J Clin. Microbiol. 13:58-61, 1981), we indicated that the Repliscan system did not reliably identify Enterobacteriaceae. Recent improvements in the system prompted us to evaluate Repliscan II (Cathra International, Inc., St. Paul, Minn.) by using representative isolates of the population sample previously used to test the system. Isolates (692) representing eight genera were identified in parallel by the Repliscan II and API 20E (Analytab Products, Plainview, N.Y.) systems. Isolates given different identifications by the two systems were assigned reference identifications by using classical microbiological methods. Repliscan II identified 95.2% correctly, 4.0% incorrectly, and 0.7% as unknown. API 20E identified 99.4% correctly, 0.6% incorrectly, and none as unknown. Repliscan II correctly identified Salmonella and Shigella spp. to the genus level and isolates of six other genera to the species level as follows: Salmonella spp., 100%; Shigella spp., 97.7%; Escherichia spp., 95.2%; Citrobacter spp., 82.1%; Enterobacter spp., 85.2%; Klebsiella spp., 98.6%; Proteus spp., 97.2%; and Serratia spp., 97.9%. These findings indicate that Repliscan II is a significantly improved system and provides acceptable identification of Enterobacteriaceae.