Code: DR0575

This kit is a streptococcal grouping test utilising nitrous acid extraction for the rapid identification of b haemolytic streptococci of Lancefield types A, B, C, F & G.

Introduction
b-haemolytic streptococci can be differentiated into Lancefield groups based on specific carbohydrate antigens¹. Differentiation is necessary for clinical treatment and for epidemiological purposes². For extraction of the group specific antigen prior to grouping a variety of methods have been used including hot acid¹, hot formamide³ and enzyme extraction methods^4,5. The Oxoid Streptococcal Grouping Kit (DR585) utilises an enzyme extraction technique. This requires a 10 minute incubation period and efficiently extracts streptococci of Lancefield Groups A, B, C, D, F and G⁶. The Oxoid Nitrous Acid Kit is based on modified nitrous reagents^6,7, which will rapidly extract the group antigens without the requirement for any incubation. However, the group D antigen is not extracted as efficiently and therefore an alternative method must be used to confirm suspected group D streptococci.

Principal of the Test
The test is intended for use with streptococcal colonies that are b-haemolytic on blood agar. The group specific antigens are extracted from streptococci by using an instant room temperature nitrous acid extraction procedure. The extract is then neutralised and the antigens are identified by agglutination.

DR0576 Extraction Reagent 1
One bottle containing 8 ml of sodium nitrate solution with a pH indicator. The reagent contains 0.095% sodium azide.
DR0577 Extraction Reagent 2
One bottle containing 8 ml of 0.4N hydrochloric acid.
DR0578 Extraction Reagent 3
One bottle containing 8 ml of a neutralising solution with 0.095% sodium azide.
DR0586 Latex Grouping Reagent A
DR0587 Latex Grouping Reagent B
DR0588 Latex Grouping Reagent C
DR0590 Latex Grouping Reagent F
DR0591 Latex Grouping Reagent G
DR0592 Polyvalent Positive Control
DR0500 Disposable Reaction Cards
Instruction Leaflet

Material Required but not Provided
Microbiological loop
12 x 75 mm test tubes
Pasteur pipette
Suitable laboratory disinfectant
For full proceedure please see product insert.

Precautions
Reagents contain 0.095% sodium azide as a preservative. Sodium axide is toxic and may react with lead or copper plumbing to produce metal azides which are explosive by contact detonation. To prevent azide accumulation in plumbing flush with copious amounts of water immediately after waste disposal.
Specimen materials may contain pathogenic organisms, handle with the appropriate precautions. The extraction procedure may not kill bacteria therefore the extract must be handled with the same precautions.
Extraction Reagents 1, 2 contain a mild irritant and a weak acid respectively. Avoid direct contact by wearing suitable protective equipment. If the material comes into contact with the skin, mucous membranes or eyes immediately wash the area by rinsing with plenty of water.

Storage
This kit should be stored 2-8°C. Do not freeze. The kit should not be used after the expiry date printed on the outside of the carton.

References
1. Lancefield R.C. (1938) Proc. Soc.Exp. Biol. 38: 473-478.
2. Facklam R.R. and Washington J.A. II. (1991) Streptococcus and Related catalase-Negative Gram-Positive Cocci. p.238-257. In A. Balows, W. Hausler, K.L. Herrmman, H.D., Isenberg and H.J. Shadomy (Ed) Manual of Clinical Microbiology, 5th Ed. American Society for Microbiology, Washington, D.C. Pages 238-257.
3. Fuller A.T. (1938) Brit. J. Exp. Path. 19: 130-139.
4. Maxted W.R. (1948) Lancet, ii. 255-256.
5. Ederer G.M., Herman M.M., Bruce. R., Matsen J.M. and Chapman S.S. (1972) Appl. Microbiol. 23: 285-288.
6. Data on File, Oxoid.
7. El Kholy A., Wannamaker L.W. and Krause R.M. (1974) Appl.Microbiol., 28: 836-839.
8. Birch B.R., Keaney M.G.L. and Ganguli L.A. (1984) J. Clin. Pathol. 37: 1289-1292.
9. Harvey C.L. and McIllmurray M.B. (1984) Eur. J. Clin. Microbiol. 3: 526-530.
10. Hopfer R.L., Pinzon R., Wenglar M. and Rolston K.V.I. (1985) J.Clin.Microbiol., 22: 677-679.
11. Lee P-C. and Wetherall B.L. (1987) J. Clin. Microbiol. ``Cross-Reaction between Streptococcus pneumoniae and Group C Streptococcal Latex Reagent’’. 25: 152-153.
12. Lawrence J., Yajko D.M. and Hadley W.K. 1985 J. Clin. Microbiol. 22: 772-777.