Evaluation of the Mini-ID Enterobacteriaceae screen system.

A total of 932 typical and atypical enteric fermenters were used to evaluate the Mini-ID Enterobacteriaceae Screen/Identification System. At 4 h, final identifications were available for only 13.3%, but an additional 71% were screened into the correct group, according to the product's database. At 24 h, 58.8% were correctly identified to the species level, often with the use of an additional tube. When 118 of the cultures were arranged into a weighted assortment, as might be found in a clinical laboratory, 35 were definitively identified at 4 h, and another 72 were screened into the correct group. Of these 72, 31 were correctly identified to the species level at 24 h, for a total of 56.0%. False-negative ornithine and incorrect L-pyrrolidonyl-beta-naphthylamide and glucuronide xylopyranoside reactions accounted for 54% of the identification errors, while database problems accounted for 10.2% of the errors. Of the eight Salmonella paratyphi A cultures, seven were missed because of a false-positive lysine reaction. At best, the system serves only as a rough screen.