It has become necessary to change our screening strategy for anti-nuclear antibodies (ANA) from the current manual HEp-2 Indirect ImmunoFluorescence (IIF) to an automated EliA Connective Tissue Disease (CTD) test which uses a panel of recombinant antigens to detect highly specific ANAs.
Our internal validation indicates that the EliA CTD shows excellent concordance with samples reported ANA positive (>=160) by IIF. In addition, the introduction of the EliA CTD screen will also improve detection of Ro positive samples.
Although this is a change in our ANA screening approach, it will impact mainly on the negative samples and follow-up testing and reporting will remain unchanged. Thus, any samples that test negative by the EliA CTD screen will be reported as ANA negative. Samples that test positive by the EliA CTD screening test they will be retested by IIF and the pattern and titre will be reported as we do currently.
Based on the excellent concordance between the EliA CTD and IIF ANA this change will have a minimal impact on your current services.
What to expect:
You will notice a quicker reporting turnaround time for ANA negative samples tested by the EliA CTD assay and an improvement in the detection rate of Ro positive samples.
You will not observe any changes in the reporting of positive ANA ENA, dsDNA positive samples.
We believe that this change will not impact significantly on your service and we are happy to discuss any issues that may incur.
See the attached letter sent to key users of the ANA service from the Laboratory Director Prof Peter Kelleher
Please contact the laboratory by emailing firstname.lastname@example.org should you wish further information about this change