Comparative evaluation of automated reading versus visual interpretation with the BBL Crystal entericonfermenter identification system in a clinical setting.

摘要

The BBL Crystal entericonfermenter identification system (Becton Dickinson, Sparks, MD, USA) is a miniaturized commercial system that is widely used to identify more than 500 gram-negative bacilli [1-4]. The system is designed to identify members of the family Enterobacteriaceae as well as common isolates of clinically significant glucose-nonfermenting gram-negative bacilli. Many of the tests used in this system are modifications of classical methods. Included among them are tests for fermentation, oxidation, degradation and hydrolysis of various substrates. In addition, there are chromogen-Hnked substrates to detect enzymes used by microbes to metabolize various substrates. The reaction patterns are converted into a ten-digit profile number. In addition, indole and oxidase tests are performed. The reaction patterns for the substrates of a wide variety of gram-negative bacilli are stored in the BBL Crystal identification database. Identification is achieved by comparing the substrate reaction patterns of the test isolate with those stored in the database.