Scheme Description
HLA testing can be performed as an aid to disease diagnosis, one of the most commonly tested being HLA-B27 which is associated with, e.g. ankylosing spondylitis.
Purpose
To assess participants’ ability to correctly determine the HLA-B27/B2708/B*27 status as positive or negative. Participants should use technology routinely employed by their laboratory to determine the B27 status (e.g. flow cytometry, molecular methods).
Samples
A total of ten blood samples will be sent each year as five distributions of two blood samples.
Reporting
Participants are required to report on HLA-B27/B2708/B*27 status as “positive” or “negative”.
An “equivocal” report is accepted for laboratories that are unable to determine a positive or negative result (i.e. by flow cytometry) and their normal clinical procedure would be to refer the sample to another laboratory.
Technical failures and other issues should be reported as ‘not tested’.
Participants must only use the reporting forms provided within the UK NEQAS for H&I Participant’s Portal and make their report within 14 days.
Assessment
The “HLA-B27” status of each sample is determined by at least 75% of laboratories agreeing on the presence or absence of “HLA-B27”. A reference result will be used for assessment for samples failing to reach the 75% consensus level.
Assessment Procedure
Each sample report in agreement with the consensus/reference “HLA-B27” status – Acceptable
Each sample report not in agreement with the consensus/reference “HLA-B27” status – Unacceptable
Each sample not reported – with valid reason, or equivocal result – Not Assessed
Each sample not reported / late submission of results – Unacceptable
Satisfactory Performance
Satisfactory performance is making ten sample reports in agreement with the consensus/reference “HLA-B27” status in a year.
Laboratories with unsatisfactory performance will receive written notification of their status and will be expected to reply to UK NEQAS for H&I detailing their corrective actions. For UK laboratories, unsatisfactory performance will be reported to UK NQAAP for Immunology. For UK laboratories, failure to reply or replies deemed unsatisfactory are likely to be further actioned by UK NQAAP for Immunology.
Information/Analysis Provided to Participants
- The HLA-B type of the donor samples (for indication only).
- Anonymised summary table of all participant results, comments and methodology. Including sample assessment result (acceptable/unacceptable classification) for each participant.
- End of year summary of participant performance.