Session Information
Date: Sunday, November 8, 2015
Title: Systemic Lupus Erythematosus - Clinical Aspects and Treatment Poster Session I
Session Type: ACR Poster Session A
Session Time: 9:00AM-11:00AM
Background/Purpose:
SLE is associated with a broad spectrum of autoantibodies, but currently there is no single serologic test to diagnose SLE definitively. Diagnosis is thus based on multiple ACR or SLICC criteria, including autoantibodies taken together in routine clinical settings. Anti-nuclear antibody (ANA) testing is a standard procedure in evaluating suspected lupus patients. While the test is highly sensitive [97 percent of patients with lupus will have a positive ANA test(1) (ANA+)], the test has poor specificity since approximately 13.8 % of healthy individuals test positive at a 1:80 dilution(2). As a result, ANA+ results can be misleading, leading to patient concern, unnecessary testing and even inappropriate therapy (3). A test to rule out the diagnosis of lupus in ANA+ patients without disease would be a valuable adjunct to current serological testing and important application of the SLE-KeyTM Rule Out technology.
Methods:
We previously developed the SLE-keyTM Rule Out test to exclude the diagnosis of SLE based on the iCHIP®(4) by profiling 250 SLE patients compared to 250 healthy controls and developing classifier algorithms. In the current study, serum samples from 136 self-declared healthy controls were available for comparative ANA testing and were sent to an external lab for fluorescence ANA (fANA) analysis.
Results:
Four different classification methods (support vector machine, Logistic regression, linear discriminant analysis and Quadratic discriminant analysis) were used to develop and validate classifier algorithms to differentiate SLE patients from the ANA positive and negative healthy subjects. Of the 136 healthy samples, 24 samples (17.6%) were found to be ANA+ at the dilution of 1:80 by fANA testing. The SLE-KeyTM classification models excluded SLE in up to 80% of these ANA+ subjects, depending on the particular statistical model.
Conclusion:
SLE-KeyTM classifiers can successfully rule out the diagnosis of SLE in up to 80% of ANA+ subjects depending on the analytic approach. These initial findings suggest that the iCHIPTM technology can be applied to develop more refined classifications to rule out SLE in the ANA+ population.
References:
(1) Kavenaugh A et al. Arch Pathol Lab Med: Jan 2000, Vol. 124, No. 1, pp. 71-81
(2) M. Satoh M et al. Arthritis Rheum. 2012 July; 64(7): 2319–2327.
(3) Slater CA, Davis RB, Shmerling RH. Antinuclear antibody testing: a study of clinical utility. Arch Intern Med. 1986; 156:1421–1425.
(4) Fattal, I, et al; Immunology 2010, 130, 337-343
Acknowledgements: The authors wish to acknowledge the invaluable contributions of Ornit Cohen-Gindi, Miriam Lerner, Naama Shefer, Ilana Gilkaite, Angela Turner, Anat Reiner-Benaim and Nazanin Mishrani
To cite this abstract in AMA style:
Batty DS, Cohen IR, Putterman C, Jordan N, Jakobi K, Sorek R, Blumenstein Y, Safer P, Pisetsky D. SLE-KeyTM Rule-out Test to Assess Lupus in Anti-Nuclear Antibody Positive Subjects Using the Immunarray iCHIP® [abstract]. Arthritis Rheumatol. 2015; 67 (suppl 10). https://acrabstracts.org/abstract/sle-keytm-rule-out-test-to-assess-lupus-in-anti-nuclear-antibody-positive-subjects-using-the-immunarray-ichip/. Accessed .« Back to 2015 ACR/ARHP Annual Meeting
ACR Meeting Abstracts - https://acrabstracts.org/abstract/sle-keytm-rule-out-test-to-assess-lupus-in-anti-nuclear-antibody-positive-subjects-using-the-immunarray-ichip/