6.7 ± 0.2

This is a chromogenic medium based on CLED that has been developed to allow differentiation and presumptive identification of organisms typically found in urinary tract infections. Reduced electrolyte concentration prevents swarming of Proteus spp. A sophisticated binary chromogenic system and supplementation with tryptophan allows differentiation of Enterococcus spp. (turquoise colonies), Proteus spp. (clear colonies with a brown halo), Enterobacter spp. (metallic blue colonies), Staphylococcus spp. (white colonies), and E. coli (purple colonies).

Recent developments in culture media have given rise to the use of chromogenic substrates as a means of differentiating bacteria particularly among the coliform group of organisms. This is one such medium and has been developed with the aim of simplifying the differentiation and presumptive identification of the main organisms usually found in Urinary Tract Infections. Based on the traditional CLED Medium, to prevent the swarming of Proteus spp, two chromogens are present in the medium. One allows the detection of enterococci giving rise to blue colonies whilst the second results in purple colonies of E. coli. Phenylalanine and Tryptophan are also included as indicators of Tryptophan deaminase activity producing brown colonies of Proteus spp. This media is an opaque version to aid differentiation and presumptive identification of the bacteria isolated.