ID- M. CAT.

INTENDED USE

The Gibson ID- M. CAT. is designed for the detection of butyrate esterase activity from clinical isolates grown on culture media as an aid in the presumptive identification of Moraxella (Branhamella) catanhalls.

SUMMARY AND EXPLANATION

Indoxyl butyrate is a substrate which is hydrolyzed by the butyrate esterase produced by Moraxella catarrhalis.¹

Moraxella catarralis cause infections such as otitis media, sinusitis, bronchopneumoniae, systemic diseases including endocarditis and meningitis.²

Different tests have been reported for the rapid identification of Moraxella catanhalis, including Tn butynn hydrolysis and indoxyl butyrate hydrolysis.

PRINCIPLES

The Gibson ID- M. CAT. utilizes filter paper stnps impregnated with a substrate for butyrate esterase. This test is based on the ability of Moraxella catanhalis to hydrolyze the substance indoxyl butyrate. The enzyme butyrate esterase breaks the ester linkage between butyryl groups liberating indoxyl. The indoxyl molecules react to form indigo in the presence of oxygen yielding a distinct bluejireen color on test cards.

MATERIALS PROVIDED

20 Test Cards

Deionized Water

This test is for IN VITRO DIAGNOSTIC USE only. Precautions should be taken against the dangers of microbiological

hazards.

Specimens, containers, media, and test cards should be sterilized after use.

STORAGE: The ID- M. Cat kit must be stored at 2-8C to prevent breakdown of the substrates and reagents. The kit must be at room temperature before use, and may be left at rcom temperature for up to one hour.

EVIDENCE OF DETERIORATION: Test should not be used if the expiration date has passed. Discard the product if the white filter paper within the test circle shows signs of discoloration. If any deficiencies are noted with this product notify the manufacturer.

SPECIMEN COLLECTION

Clinical specimens should be protected from excessive heat and cold and should be delivered to the laboratory without delay. The specimen should be collected prior to the initiation of therapy. If the specimen is collected after the initiation of therapy, the microbiologist should be notified on the data form. Additional information on the collection of clinical specimens may be found in standard reference texts. Fresh cultures 24-72 hours old give best results. Use pure cultures of oxidase positive, gram negative dipplococci exhibiting typical colonial morphology.

PROCEDURE

MATERIALS REQUIRED BUT NOT PROVIDED: The standard clinical microbiological equipment such as loop, burner,

and incubator are needed for procedures involving the use of this product. Other materials required include the following:

Oxidase reagents, Gram Stain Reagents, Microscope slides, Culture Media, and American Type Culture Collection

(ATCC) strains- Moraxella catanhalis ATCC 25240 and Neisseria gononhoeae ATCC 43069.

Use one card for each specimen tested. Before performing the test make sure to use a pure culture of oxidase positive, gram negative, diplococci exhibiting typical colonial morphology.

1. Remove one test card and add ONE DROP of deionized water to the test circle. ALLOW 90 SECONDS FOR TEST CARD TO DRY BEFORE INOCULATION.

2. Using an applicator stick or Icop, pick up 34 colonies equal to or greater than 4 mm from a

24-72 hours pure culture and mb on the moistened circle.

3. Incubate at rcom temperature for up to 5 minutes.

4. Read color change within the 5 minutes. The formation of a blue~reen color on the test card is a positive reaction. The organisms can be presumptively identified as Moraxella (Branhamella)

catarrhalis. No color change is a negative test.

INTERPRETATION

USER QUALITY CONTROL

Daily quality control should be performed in accordance with proper laboratory procedures using organisms that will produce known positive and negative reactions. Follow steps 14 under PROCEDURE section. If quality control results are false clinical results should not be recorded. Notify the manufacturer if proper results are not obtained. The following American Type Culture Collection strains are recommended:

Organism

Moraxella catanhalis

ATCC 25240

Neisseda gononhoeae

ATCC 43069

Test Circle

Bluegreen color change (Positive)

No color change (Negative)

LIMITATIONS OF PROCEDURE

Longer incubation times and excessive moisture may give false positives, allow test card to dry for 90 seconds and read test within 5 minutes. Some species of Staphylococcus (gram positive), Pseudomonas (rods), and Candida (gram positive) may give a positive test. Use of only gram negative, oxidase positive, diplococci should prevent the misidentification of the above organisms. Animal species, Branhamella caviae and Branhamella avis, give a positive result but are rarely encountered in pathological specimens. False negatives may result from using tco small an inoculum. The Gibson ID- M.Cat. is designed as an aid in the presumptive identification of Moraxella catanhalis. Definitive identification should be done using established test procedures.²

PERFORMANCE STUDIES

The Gibson ID- M CAT. test was tested on 55 dinical isolates. The isolates consisted of 20 Maraxella species, 15 Neisseria species, 7 Candida species, 5 Staphylococcus species, and 5 Pseudomonas species. The Gibson ID- M. CAT. correctly identified all Moraxella species showing positive results. All Neisserla strains produced negative results. All Staphylococcus, Pseudomonas, and two Candida strains gave positive results. However, it should be noted that examination of colony morphology, gram-stains, and oxidase test results should prevent the misidentification of these isolates.

REFERENCES

1. Dealer, S.F., et al. 1989. Identification of Branhamella catarthalis in 2.5 mm with an Indoxyl Butyrate Strlp Test. J. Clin. Microbial. 27:1390-1391.

2. Knapp, J.S. and R.J. Rice. 1995. Neisserla and Branhamella. Pages 324-340 in P.R. Murray, E.J. Baron, M.A. Pfaller, F.C. Tenaver, and R.H. Yalken, eds. Manual of Clinical Microbiology. 6th ed. Amer. Soc. for Microbial., Washington, D.C.

3. Janda, W.M. and P. Ruther. 1989. B.CAT-CONFIRM, A Rapid Test for Confirmation of Branhamella catanhalis. J. Clin. Microbial. 27:1130-1131.

4. Riou, Y.J. et al. 1981. Hydrolyse De La Trlbutyrlne Par Les Neisserla et Les Branhamella. Ann. Microbial. (Inst. Pasteur). 13~:159-169.

5. Vaneechoutte, M., et al. 1988. Rapid Identification of Branhamella catarrhalis with 4-Methylumbelliferyl Butyrate. J. Clin. Microbial. 26:1227:1228.