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Quality Assurance Unit - Scheme Details

PT Number
Scheme title
Staphylococci including MRSA (Methicillin-Resistant Staphylococcus aureus) - Culture / Identification / PCR
Suitable testing methods
Culture / PCR
Reporting format

Participants are to record:

  1. Bacterial species and methicillin-susceptible or resistant at least for all S. aureus isolates and preferably for all isolates.
  2. Results for the following tests, where these have been used:
    1. Coagulase (method used - tube, slide or kit),
    2. Methicillin susceptibility (method used, plus quantitative result),
    3. Oxacillin susceptibility (method used, plus quantitative result),
    4. Cefoxitin susceptibility (method used, plus quantitative result),
    5. PBP2' result (where used),
    6. mecA result (if done).
  3. Whether the isolate is considered to be MRSA. [MRSA is defined as S. aureus with methicillin resistance conferred by the presence of the altered penicillin binding protein PBP2’]

Final report will be published electronically showing all participants results

Results to be returned within
21 days
Number of samples in each distribution
Sample Type
0.1mL freeze-dried sample in glass vial.
In each distribution there will be a panel of 7 staphylococcal isolates, these may include S. aureus, S. pseudintermedius (formerly called S. intermedius) and coagulase negative staphylococci for identification, determination of methicillin susceptibility and identification of MRSA
Packaging and transport details
UN3373 – Biological substance category B. Courier delivery required which will incur additional charges. Please contact the QA unit for further details
Number of distributions per year
Accreditation Status
ISO/IEC 17043: 2010 Conformity assessment General requirements for proficiency testing.
Date scheme started
Pre 2009

The scheme has two objectives and participants may wish to take part in either or both of these: 

  1. To correctly identify all staphylococcal strains, determine their methicillin susceptibility and which are MRSA.
  2. To correctly determine which of the strains are MRSA.

The nomenclature of Staphylococcus intermedius has recently changed and most isolates formerly called S. intermedius from dogs are now properly called S. pseudintermedius (Devriese 2009). For the purposes of the QA exercise, where a S. intermedius is included in the panel, identification of isolates belonging to the S. intermedius group to the level of S. intermedius, S. pseudintermedius and S. delphini is not required and isolates can be identified to the “intermedius complex” level.

For price and detail of distribution months please see price list or contact:

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