MASTASTAPH™

Rapid latex agglutination slide test for Staphylococcusaureus

Staphylococcus is one of the most common genera to be isolated in the routine diagnostic laboratory.Traditional differentiation of S. aureus from other members of the genus has mainly involved slide ortube coagulase tests which are regarded by some workers as being unreliable and laborious toperform. MASTASTAPH� is a rapid, slide agglutination test offering a convenient, reliable alternativeto coagulase tests.

MASTASTAPH� is based on the test principle described by Essers and Radebold who showed thatthe presence of bound coagulase (clumping factor) and Protein A could be detected using humanplasma coated latex particles. MASTASTAPH� latex reagent contains particles coated with fibrinogenand IgG. If mixed on a slide with S. aureus organisms, cell bound coagulase reacts with fibrinogenand/or protein A reacts with IgG causing rapid agglutination of the latex particles.

Convenient • Simple 3 step test procedureusing liquid, ready to usereagents

Reliable • MASTASTAPH� identifies bothclumping factor and protein A

Easy to read • Clear, well definedagglutination patterns

Rapid • Most positives occur within 20seconds

Contents

MASTASTAPH™ contains the followingcomponents:1. Latex Reagent, ready to use. 2 x 3ml. Latex

particles coated with human fibrinogen and IgGin phosphate buffered saline, pH 6.8. Containsless than 0.1% sodium azide as preservative.

2. 30 disposable 4-place test cards.3. 120 single use disposable Mixing Sticks.4. Instruction leaflet.

Product code: RST 101Pack size: 120 tests

Stability and storageStore unopened at 2-8°C until the expiry dateshown on the pack label. Once opened,MASTASTAPH™ should be stored at 2-8°C andmay be used until the expiry date given on the label.Do not freeze latex reagents.

Warnings and precautions

For in vitro diagnostic use only. Observe approvedbiohazard precautions and aseptic techniques. Tobe used only by adequately trained and qualifiedlaboratory personnel. Sterilise all biohazard wastebefore disposal. Sodium azide preservative may betoxic if ingested and may react with lead and copperplumbing to form highly explosive salts. Alwaysdispose of by flushing to drain with plenty of water.Refer to Product Safety Data sheet for furtherinformation.

Procedure

1. Allow the MASTASTAPH� Latex Reagent toequilibrate to room temperature before use.

2. Shake well and then add 1 drop ofMASTASTAPH� Latex Reagent into a circle onthe MASTASTAPH� Test Card.

3. Using a clean mixing stick, pick up 2-4 averagesize colonies from a fresh overnight culture plateand emulsify the colonies in the latex, mixingthoroughly and spreading over half the area ofthe circle. Discard the stick into disinfectant.

4. Rotate and rock the card slowly and read within1 minute.

5. Record result and dispose of the test cardsafely.

Interpretation of results

A positive result is indicated by visible aggregationof the latex particles with a clear background. Thiswill occur within seconds of mixing.

A negative reaction is indicated by a milkyappearance without any visible aggregation of thelatex particles.

Faint traces of granularity or string-like appearancewithout clearing of the background may be detectedin negative patterns depending on the visual acuityof the operator.

For the specific detection of Methicillin ResistantStaphylococcus aureus (MRSA), the MASTALEX�

MRSA test kit (RST501) is recommended.

Limitations of use

Only freshly grown overnight cultures of organismsshould be used for testing directly from the plate. Ifthere is insufficient growth the organism should besub-cultured onto Mast Blood Agar Base (DM100)or Mast Nutrient Agar (DM179) and incubatedovernight at 37°C. Organisms grown on high saltmedium such as Mannitol Salt Agar may showsigns of stringiness when mixed with the latexreagent. Sub culturing onto Mast Blood Agar Base(DM100) or Mast Nutrient Agar (DM179) will avoidthis problem.

Some species of staphylococci other than S. aureus(notably S. intermedius and S. hyicus) may givepositive results in conventional coagulase test andmay also agglutinate latex reagents. Rare speciessuch as S. lugdunensis and S. schleiferi have beenreported as clumping factor positive. Novobiocinresistant strains may also give false positive resultsusing latex based tests. Several species such asEscherichia coli and Candida albicans are capableof non-specifically agglutinating latex particles.Organisms that possess immunoglobulin bindingfactors may also agglutinate the sensitised latex.

Quality control

Check for signs of deterioration. Quality controlmust be performed with at least one organism todemonstrate expected performance. Do not usethe product if the result with the control organism isincorrect. The list below recommends the controlstrains which the end user can easily obtain.

Test Organisms ResultStaphylococcus aureusATCC� 25923

Positive in 20seconds

Normal saline solution Negative

References

Bibliography available on request.

AK 06/06 v1.3MAST is a Registered Trademark

ATCC is a trademark of the AmericanType Culture Collection, Manassas, Virginia, USA