Evaluation of the BBL Crystal Enteric/Nonfermenter kit for the identification of water-derived environmental Enterobacteriaceae.

The Crystal Enteric/Nonfermenter (E/NF) identification kit (Becton Dickinson Microbiology Systems, USA) was evaluated using water-derived bacterial isolates and results compared to those obtained by the API 20E system (BioMérieux, UK). Both the E/NF and 20E systems correctly identified 93% of the Enterobacteriaceae reference cultures. Both systems agreed in the identification of 64.9% of environmental isolates. The E/NF system gave a positive identification to 88.0% of isolates and the 20E to 79.5% of isolates. The principal tests which gave differing reactions between the two systems were arginine dihydrolase, lysine decarboxylase, urease and citrate utilization.