Evaluation of a rapid tube assay for presumptive identification of Escherichia coli from veterinary specimens

Abstract

Three hundred sixty-six isolates of gram-negative, oxidase-negative bacteria from veterinary specimens were tested by a tube test for identification as Escherichia coli by production within 60 min of indole, .beta.-galactosidase, and .beta.-glucuronidase. The test correctly identified 255 of 269 isolates of E. coli (95% sensitivity) and correctly indicated that 97 of 97 isolates were not E. coli (100 % specificity). We conclude that production of indole, .beta.-galactosidase, and .beta.-glucuronidase as measured by a rapid tube test is useful for identification of E. coli from veterinary specimens.