ELIchrom Coryne

Market Segment: ,

Simple identification of the coryneform bacteria and related species.

ELIchrom CORYNE is a complete routine laboratory test enabling the identification of the principal coryneform bacteria within 24 hours. Furthermore, it allows precise identification of Listeria and propionobacteria, often confused with corynebacteria.

  • Complete, cost-effective, routine laboratory test
  • Multiple species identified
  • High sensitivity and specificity
  • Accurate results available in 24 hours
  • Simple colorimetric reaction, without expert interpretation
  • Operator safe diagnostic reagents

Catalogue Number(s)

22800
Product Description: ELIchrom CORYNE
Number of Tests: 12 test

2801
Product Description: ELIchrom CORYNE Code Book
Number of Tests: 1 CD-ROM

Intended Use

Corynebacterium diphtheriae is a pathogenic specie, responsible for diphtheria and systemic infections. Certain commensal species such as Corynebacterium urealyticum and Corynebacterium jeikeium can also become pathogenic.

Increasing numbers of immuno-depressed patients and the development of invasive hospital techniques are reasons for the increasingly frequent isolation of corynebacteria strains, which requires identification methods adapted to medical analysis laboratories.


Principle

ELIchrom CORYNE is a ready-to-use test featuring a 20 well tray with dehydrated substrates.
Identification using 20 biochemical characters is based upon the presence or the absence of various enzymes visualized by color change reactions.

The enzymatic activities are highlighted by the following reactions:

  • Hydrolysis of chromogenic substrates involving the release of colored molecules.
  • Hydrolysis of urea: with release of ammonia and alkalization of the medium that leads to the indicator (phenol red) turning from orange to fuchsia.
  • Hydrolysis of esculin producing esculetin, which when coupled with ferric ammonium citrate forms a black precipitate.
  • Clark and Lubs Mediumenables the visualization of strong acidification of the medium (RM) following incubation and addition of RM reagent.
  • Use of sugars, which results in acidification of the medium with the indicator (bromoxylenol blue) turning from blue to yellow.

The substrates present in the wells are reconstituted with a bacterial suspension prepared from isolated colonies.

After incubation of the tray for 24 hours at 37°C, the biochemical reactions are read with the naked eye via a spontaneous color change reaction or following the addition of a revelation reagent.

Interpretation of the identification results is carried out with the aid of codes and a results interpretation table included with the kit.


Simple Protocol

methodology


Easy-to-read and easy-to-interpret results

The result is visualized by a simple spontaneous colorimetric reaction, without instrument or expert interpretation.
Identification table & coding system (code book) are available for the interpretation of the results. It is a practical and easy-to-use laboratory test, giving accurate results from isolated colonies usually in 24 hours.
elichrom_coryne_results[1]

Reagents and Material

  • SUSPENSION CORYNE:
    2.5 mL vial of liquid medium for the standardization of the inoculum Quantity: 14TC
  • TC CORYNE:
    2.5 mL vial of barium sulphate solution for turbidity control (Mc Farland 4/4.5) Quantity: 1RM
  • RM CORYNE:
    2 mL vial of methyl red solution for revelation after incubation of the RM test (well 10) Quantity: 1
  • ELIchrom CORYNE Tray:
    20 wells tray, individually packed in an aluminum sachet, and containing the substrates described below Quantity: 12

Stability and Storage

The reagents when stored at 2-8 °C in their original state are stable until the expiry date indicated on the box. The SUSPENSION CORYNE medium as well as the ELIchrom CORYNE tray are ready-to-use and should be used immediately after opening. The RM CORYNE is stable after opening.

Performance

The performance evaluation was carried out using 136 collection strains or freshly isolated strains from clinical specimens (2 Arthrobacter spp, 4 Archanobacterium haemolyticus, 2 Archanobacterium pyogenes, 1 Brevibacterium spp, 8 Corynebacterium accolens, 9 Corynebacterium afermentans, 14 Corynebacterium amycolatum, 4 Corynebacterium argentoratense, 1 Corynebacterium aurimucosum, 1 Corynebacterium diphteriae, 4 Corynebacterium diphteriae gravis, 5 Corynebacterium diphteriae mitis, 6 Corynebacterium glucuronolyticum-seminale, 13 Corynebacterium jeikeium, 6 Corynebacterium minutissimum, 5 Corynebacterium propinquum, 7 Corynebacterium pseudodiphteriticum, 8 Corynebacterium pseudotuberculosis, 1 Corynebacterium simulans, 15 Corynebacterium striatum, 6 Corynebacterium ulcerans, 10 Corynebacterium urealyticum, 2 Dermabacter hominis, 1 Erysipelothrix rhusiopathiae, 1 Rhodococcus equii).

The comparative study was carried out in parallel with the mass spectrometry method. The percentage of agreement between the two methods was 98.5%. Among the strains identified by ELIchrom CORYNE, 58.2 % were identified with a unique code.

Material required but not provided

  • ELIchrom CORYNE Codebook (Ref. 22801)
  • Paraffin oil
  • Sterile pipettes
  • Automatic pipette (100 μL)
  • Incubator at 37 °C
  • Container for contaminated waste