Part of Thermo Fisher Scientific
Organisms this product works with:
Other products used in the isolation of Urinary pathogens :
BRILLIANCE UTI AGAR
Brilliance™ UTI Agar (formerly Chomogenic UTI Agar ) is a chromogenic medium for the presumptive identification and differentiation of all the main micro-organisms that cause urinary tract infections (UTIs).
Products available
| Size/format | order code |
Dehydrated Culture Media | 500g | CM0949B |
Ready-Poured Plates (UK) | 10 x 90mm plates | PO0794A |
Ready-Poured Plates (rest of Europe) | 10 x 90mm plates | PO5120A |
Typical Formula* | gm/litre |
Peptone | 15.0 |
Chromogenic mix | 26.3 |
Agar | 15.0 |
Final pH 6.8 ± 0.2 @ 25°C |
Directions
Suspend 56.3g of Brilliance UTI Agar in 1 litre of distilled water, mix well and sterilise by autoclaving at 121°C for 15 minutes. Cool to 50°C and mix well before pouring plates.
Description
Brilliance UTI Agar contains two specific chromogenic substrates which are cleaved by enzymes produced by Enterococcus spp., Escherichia coli and coliforms. In addition, it contains phenylalanine and tryptophan, which provide an indication of tryptophan deaminase activity, indicating the presence of Proteus spp., Morganella spp. and Providencia spp. It is based on electrolyte deficient CLED Medium which provides a valuable non-inhibitory diagnostic agar for plate culture of other urinary organisms, whilst preventing the swarming of Proteus spp.
One chromogen, X-Gluc, is targeted towards β-glucosidase, and allows the specific detection of enterococci through the formation of blue colonies. The other chromogen, Red-Gal, is cleaved by the enzyme β-galactosidase which is produced by Escherichia coli, resulting in pink colonies. Any uncertainty in identification may be resolved by removing suspect Escherichia coli colonies from the plate and performing an indole test using DMACA reagent. Cleavage of both chromogens occurs in the presence of coliforms, resulting in purple colonies (see Table 1).
The medium also contains tryptophan which acts as an indicator of tryptophan deaminase activity, resulting in colonies of Proteus, Morganella and Providencia spp. appearing brown.
Table 1: typical colour reactions
Organism | β-galactosidase | β-glucosidase | Tryptophan deaminase (TDA) | Colony colour |
Enterococci | + | Blue | ||
Escherichia coli | + | Pink | ||
Coliforms | + | + | ||
Proteus | + | Brown | ||
Pseudomonas | Fluorescent brown or green | |||
Staphylococcus | Normal |
Oxoid Brilliance UTI Agar plates should be stored in the original packaging, at the temperature stated on the pack or product specification, and protected from direct light.
When stored as directed, the unopened product will remain stable until the expiry date on the label. Locally prepared media can be stored for up to 2 weeks when made from CM0949 according to the manufacturer’s instructions and stored at 2-8ºC, in the dark. A longer shelf life may be attainable, but should be validated under the relevant, local manufacturing and storage conditions.
Appearance
Dehydrated medium: straw coloured, free-flowing powder
Prepared medium: pale buff coloured gel
Quality control
Positive controls: | Expected results |
Escherichia coli ATCC® 25922 * | Good growth; pink coloured colonies |
Enterobacter aerogenes ATCC® 13048 * | Good growth; purple coloured colonies |
Enterococcus faecalis ATCC® 29212 * | Good growth; blue-green coloured colonies |
Proteus hauseri ATCC® 13315 * | Good growth; straw coloured colonies; brown halo |
Staphylococcus aureus ATCC® 25923 * | Good growth; white colonies |
Negative control: | |
Uninoculated medium | No change |
Precautions
Brilliance UTI Clarity Agar is for in vitro diagnostic use only, by experienced microbiologists. It must not be used beyond the stated expiry date, or if the product shows any sign of deterioration.
It should be noted that, as with all chromogenic media, organisms with atypical enzyme patterns may give anomalous reactions. The medium should be validated with locally prevalent strains to confirm sensitivity and specificity in the end-users hands, under local conditions.
A presumptive E. coli identification can be confirmed using DMAC indole reagent (do not use Kovac’s reagent as the colour of the pink colonies may be mistaken for the red colour of a positive indole result). The test should be performed on filter paper, not directly on the plate.
References
1. Data on file.
Brilliance UTI PDF (1.26MB)