Background/Purpose: Detection of anti-nuclear antibodies for the diagnosis of connective tissue diseases (CTD) often requires complex algorithms to obtain conclusive results , including immunofluorescence on Hep2 cells, ELISA multiplex anlaysis and immunoblotting, which can delay the delivery of results to the physician and the patients. The Maverick™ Detection System (Genalyte, Inc. USA) performs multiplexed detection of autoantibody binding events by measuring the shift in wavelength of ring resonance as the antibodies bind to the antigens on the surface above the rings. The ANA 13 PRI Chips are functionalized with SSA/Ro-60, Ro-52, SS-B, Sm, RNP, PCNA, RiboP, dsDNA, nucleosome, Scl-70, Ku, Centromere B and Jo-1. Just 10 µL of whole blood is required and results are obtained in less than 15 minutes. The objectives of this study were to compare the results obtained in real time on the Maverick with those from the standard procedures in the lab, and to compare those results to the patient’s diagnosis.

Methods: Whole blood from 205 consecutive patients followed-up between March and June 2016 at the Pitié-Salpétrière hospital (Paris, France) was analyzed on the ANA 13 PRI. 123 patients had systemic lupus erythematosus (SLE), 13 had Sjögren’s syndrome, 10 had primary antiphospholid syndrome, 6 had ANCA associated vasculitis, 5 had Raynaud’s phenomenon, 4 had rheumatoid arthritis, 2 had myositis and 1 systemic sclerosis. Other patients had symptoms that required the routine procedures for the diagnosis of CTD with final diagnosis different from CTD. Comparisons were made with results obtained on corresponding sera at the laboratory using IFA screening tests and confirmatory testing with FIDIS multiplex assays (THERADIAG) and when necessary Immunoblotting (D-TEK) or anti-DNA ELISA (DiaSorin), Farr assay and anti-nucleosome ELISA (Werfen).

Results: The Maverick Detection System showed excellent total, positive and negative percent agreement when compared to the final conclusion of the laboratory for Sm, Scl-70, Jo-1, SS-A/Ro 60, SS-B, Centromere, Ku antigens with total, positive and negative percent agreement above 95%, and for PCNA above 92 %. For RNP, total agreement was of 90%, positive was 100% and negative was 88.5%. Interestingly, 17 of 19 samples that were positive for RNP by Maverick but negative by the lab test, and all 8 that were positive for Sm by Maverick but negative by the lab test, were from patients diagnosed with SLE. For anti-nucleosome and anti-DNA the ANA 13 PRI displayed diagnostic performances close to commonly used ELISA systems. For Ro 52 and Ribosome P, the overall agreement and specificity were greater than 90%, but the sensitivity was lower. However, for all cases with false negative results for Ro52 and RiboP with the ANA13 PRI, other specific autoantibodies were present and detected with the ANA13 PRI. Therefore, no diagnosis of CTD would have been missed by using the ANA PRI 13.

Conclusion: The Maverick detection system, which uses whole blood as the matrix and gives results in under 15 minutes, offers a reliable rapid diagnosis solution for the search of autoantibodies in CTD.

« Back to 2016 ACR/ARHP Annual Meeting

ACR Meeting Abstracts - https://acrabstracts.org/abstract/near-patient-anti-nuclear-antibody-multiplex-testing-using-whole-blood-for-the-diagnosis-of-connective-tissue-diseases-in-a-tertiary-care-center/