Pseudomonas cepacia typing systems: collaborative study to assess their potential in epidemiologic investigations.

To determine the utility of available Pseudomonas cepacia typing systems for confirming the relatedness of isolates, we applied these methods to isolates associated with previously investigated nosocomial outbreaks. We compared chromosome analysis, serologic reactions, biochemical tests, bacteriocin production and susceptibility, and antimicrobial susceptibility in their ability to determine outbreak relatedness. Chromosome analysis, serologic reactions, and biochemical tests were each demonstrated to be epidemiologically useful methods for typing isolates. Determination of the sensitivity and specificity of these typing techniques will facilitate their application in the epidemiologic study of this increasingly important nosocomial pathogen.