Microring® XV for Haemophilus Speciation now CE Marked and ISO 9001

Microring® XV is a filter paper ring device designed to differentiate Haemophilus species on the basis of growth requirements for Haemin (X factor) and Nicotinamide Adenine Dinucleotide - NAD (V factor). Microring XV also incorporates a test for porphyrin synthesis which some microbiologists find is a more reliable means of demonstrating the requirement for X factor than using satellite growth methods.

Each Microring XV has 3 tips which are clearly labelled and impregnated with the following:

Directions of use
1 Prepare a suspension of the test organism in sterile peptone water or saline to produce an inoculum equivalent to a No. 1 McFarland standard.

2 Using a swab, spread the suspension uniformly across the surface of a medium such as Tryptone Soy Agar or Columbia Agar.

3 Using sterile forceps, place a Microring on the centre of the agar plate and press each tip lightly to ensure contact with the agar surface.


For the porphyrin test
4 Use an inoculating loop to obtain a large inoculum of the organism by taking a sweep of the culture from the primary isolation media. Spread this lightly over the surface of the V tip of the Microring which is lying on the surface of the agar plate.

5 Incubate at 37°C aerobically for up to six hours then examine the V tip of the Microring under ultraviolet light (360nm). Non-haemin requiring Haemophilus parainfluenzae and H. parahaemolyticus synthesize haemin precursors from ALA resulting in an orange/red/ fluorescence on the filter paper tip when viewed under ultraviolet light.

6 After examination for fluorescence reincubate plates aerobically at 37°C to achieve a total incubation time of 24 hours.

7 Examine plates under normal light for halos or zones of growth around one or more of the Microring tips to determine the growth requirements of the organism. Compare these findings and those of the porphyrin test with the table below to determine the identity of the test organism.

Storage: Store at 2-8ºC. Shelf life 2 years from date of manufacture.

Reference
1.In Vitro Diagnostics Devices Directive (98/79/EC), 1998, Official Journal of European Communities, L331/1

Other Microring® products available
Microring® AN Six tipped antibiotic ring for the simple identification of non-sporing anaerobes .
Microring® AC Three tipped Microring for the differentiation of? anaerobic Gram- positive cocci.
Microring® YT Convenient six tipped ring for rapid identification of yeasts within 24 hours.
Microring® GV Identification of Gardnerella vaginalis.