Evaluation of the AutoMicrobic system for identification of glucose-nonfermenting gram-negative rods

Abstract

With the Enterobacteriaceae Plus Biochemical Card, the AutoMicrobic system (Vitek Systems, Inc., Hazelwood, Mo.) is purported to identify members of the family Enterobacteriaceae and seven species of glucose-nonfermenting gram-negative rods: Pseudomonas aeruginosa, P. fluorescens, P. putida, P. maltophilia, P. cepacia, and Acinetobacter calcoaceticus (saccharolytic and non-saccharolytic). The latter capability was examined in this investigation. Of 410 glucose-nonfermenting rods included in the identification profile, the AutoMicrobic system correctly identified 366 (89.3%). Of 62 glucose-nonfermenting organisms not included in the identification profile, 41 (66%) were correctly reported as "unidentified organism." The usefulness of the AutoMicrobic system-generated identification probability in establishing criteria for acceptance of identification is discussed.