This scheme is aimed at laboratories that provide a service as an aid to the diagnosis of Class I and Class II HLA associated diseases, e.g. coeliac disease, birdshot retinopathy, actinic prurigo, psoriasis and narcolepsy (excluding HLA-B27 testing which is covered in Scheme 1B). Participants of Scheme 8 are mainly laboratories that perform partial HLA typing or use a commercial kit(s) to detect the presence of specific disease-associated HLA alleles.
As participants have different clinical requirements for the diseases they test for in terms of loci and resolution (1st or 2nd field), Scheme 8 uses a reference typing result for assessment. This means that laboratories participating in Scheme 8 are able to report the relevant HLA associated diseases at the resolution that is applicable to the needs of their clinical users. Assessment is performed by comparing the participant results to the reference type (at the 1st or 2nd field level).
Laboratories may also report interpretive comments as would appear on clinical reports, these will not be assessed in 2021-22.
Laboratories are not penalised for reporting ‘strings’ of HLA alleles e.g. DQB1*03:02/03:03 if this is the resolution they report for clinical samples.
To assess participants’ ability to correctly determine disease associated HLA allele families/alleles.
A total of ten blood samples will be sent each year as three distributions. Participants will receive three blood samples in the first shipment, four samples the second shipment and three samples in the final shipment.
There is also an option to receive pre-prepared DNA samples instead of whole blood samples. There will be a charge of £50 for this service.
At registration participants must designate the HLA associated diseases they wish to be assessed for. Scheme 8 now includes all Class I and Class II HLA associated diseases (excluding HLA-B27, see Scheme 1B).
Participants are required to report their HLA genotyping findings relevant to each disease registered for. Participants should report the loci and at the resolution they test and report clinically. Each disease must have its own report form completed. Interpretive comments for the disease risk the genotype confers, as reported clinically may also be reported (not assessed).
Participants are requested to report results using the correct nomenclature https://hla.alleles.org/.
Participants must only use the reporting forms provided within the UK NEQAS for H&I Participant’s Portal and are required to return results within 3 weeks.
Participating laboratories will be assessed on the alleles reported for each sample and disease.
Assessment will be at the 1st or 2nd field level appropriate to the individual participant’s results for each locus.
A reference result will be used for assessment. Reports of groups of alleles must include the reference allele.
Interpretive comments can be included although these will not be assessed.
Participants will only be assessed on those alleles that appear in the IMGT/HLA database update (https://www.ebi.ac.uk/ipd/imgt/hla/) from the April two years prior to the start of the Scheme (e.g. the IMGT/HLA release version 3.40 (2020-04) will be used throughout 2022-23).
Each HLA genotype in agreement with the 1st or 2nd field reference type – Acceptable
Each HLA genotype not in agreement with 1st or 2nd field reference type – Unacceptable
Each sample/disease not reported – with valid reason, or equivocal – Not Assessed
Each sample not reported / late submission – Unacceptable
Satisfactory performance is obtaining ten samples in agreement with the reference genotype in a year for each disease registered for.
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
- 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.