Comparison of the AutoMicrobic system and a conventional tube system for identification of nonfermentative and oxidase-positive gram-negative bacilli.

The AutoMicrobic system (AMS) Enterobacteriaceae-plus Biochemical Card was developed to identify a select group of 10 species of glucose-nonfermentative and oxidase-positive fermentative gram-negative bacilli. In this study, 159 nonenteric clinical isolates were identified by the AMS and conventional tube biochemicals based on E. O. King's (Centers for Disease Control) identification schema. The AMS properly identified 96.7% (117 of 121) of isolates whose taxa were included in the AMS data base. Of 38 isolates (94.7%) in which taxa were not included in the data base, 36 were correctly called unidentified organisms. A principal advantage of the AMS is the automated identification of frequently isolated nonenterics in a period of only 8 to 13 h. The AMS, with the use of the Enterobacteriaceae-plus Biochemical Card appears to be a rapid and accurate system for the identification of the most commonly isolated nonfermentative and oxidase-positive fermentative gram-negative bacilli.