Fluorogenic assay for immediate presumptive detection of Escherichia coli in urine

Abstract

A rapid and direct fluorogenic assay was used to detect Escherichia coli in urine. Most clinical isolates of E. coli produce β‐glucuronidase, whereas almost all other enterobacteria lack the enzyme. Spectrofluorimetric assay of β‐glucuronidase, without previous induction, was performed on growing and starved uropathogenic E. coli in artificial urine. The presence of 103 cfu ml‐1 of E. coli in urine was detected by β‐glucuronidase activity in less than 1 h. These results indicate that β‐glucuronidase is a rapid, specific and sensitive indicator of the presence of E. coli in urine, and provide additional information on the biological state of the infecting bacterial population.