Burkholderia, Stenotrophomonas, Ralstonia, Cupriavidus, Pandoraea, Brevundimonas, Comamonas, Delftia, and Acidovorax

This chapter talks about various environmental organisms that include Burkholderia, Ralstonia, Cupriavidus, Pandoraea, Comamonas, Delftia, Acidovorax, Brevundimonas, and Stenotrophomonas spp. in water, soil, the rhizosphere, and in and on plants including fruits and vegetables. Members of these genera are widely recognized as phytopathogens. The species discussed in the chapter grow well on standard laboratory media such as 5% sheep blood and chocolate agars. Genotyping strategy provides robust, reproducible, and portable results and is quickly becoming the preferred method for investigating bacterial epidemiology, evolution, and population structure. Repetitive-sequence PCR using a BOX A1R primer and multilocus variable-number tandem repeat analysis have been developed for B. pseudomallei to exclude a clonal outbreak. Of the organisms discussed in the chapter, B. pseudomallei is the only one for which serologic tests have been used clinically to diagnose the infection. The indirect hemagglutination assay, although not available commercially, is the most widely used test. It is performed by using a prepared antigen from strains of B. pseudomallei sensitized to sheep cells and includes unsensitized cells as a control. This assay can be adapted to a microtiter plate test system. MIC broth microdilution and the Etest are the preferred methodologies for susceptibility testing. For multiresistant strains, consideration could be given to testing for synergy with double or triple combinations of antimicrobial agents in reference laboratories. It is important to note, however, that neither checkerboard MIC broth microdilution testing nor multiple combination bactericidal antibiotic testing is standardized at present.