Ignat, et al: Autoantibody panels in SLE 1761 From the Department of Microbiology/Immunology and Department of Medicine, Section of Rheumatology, University of Illinois College of Medicine, Chicago, Illinois, USA. Supported in part by Campus Research Board, University of Illinois at Chicago. G.P. Ignat, MD; A-C. Rat, MD; J. Vo, MD; J. Varga, MD, Professor and Head, Section of Rheumatology, Department of Medicine; J.J. Sychra, PhD, Associate Professor, Department of Radiology; M. Teodorescu, MD, PhD, Emeritus Professor, Department of Microbiology/Immunology. Address reprint requests to Dr. M. Teodorescu, 6776 Fieldstone Drive, Burr Ridge, IL 60527. E-mail: oana@uic.edu Submitted July 31, 2002; revision accepted January 3, 2003. Recent guidelines on the use of tests for antinuclear anti- bodies were issued by a committee of the College of American Pathologists and the American College of Rheumatology (ACR) 1,2 . According to these guidelines, (1) measurement of panels of autoantibodies has no clinical value for the diagnosis and management of patients with systemic lupus erythematosus (SLE); and (2) measurement of antibodies against denatured DNA (ssDNA) has no clin- ical value and should be used only for research purposes. However, no publication was cited to support these 2 guide- lines. Most studies on autoantibodies in patients with SLE have focused on those considered disease markers and included in the ACR diagnostic criteria for SLE 3,4 : anti-dsDNA and anti-Sm. However, other autoantibodies have been used in the diagnosis of SLE and related syndromes, including anti- ssDNA (denatured DNA, total DNA or ssDNA), histones, nRNP, SSA (Ro), SSB (La), ribosomal protein P, and Scl- 70 5 . The presence of multiple autoantibodies in different assortments and concentrations reflects both the polyclon- ality and the diversity of the autoimmune response process in individual patients with SLE 6,7 . After the diagnosis of SLE is made, only anti-dsDNA autoantibody concentrations are routinely used as correlates or predictors of flare and disease activity 8-13 . The problem Information on Diagnosis and Management of Systemic Lupus Erythematosus Derived from the Routine Measurement of 8 Nuclear Autoantibodies GHEORGHE PAUL IGNAT, ANNE-CHRISTINE RAT, JERRY J. SYCHRA, JACQUELINE VO, JOHN VARGA, and MARIUS TEODORESCU ABSTRACT. Objective. To determine the value of routine measurement of a panel of 8 nuclear autoantibodies (ANA/8) for the diagnosis and management of patients with systemic lupus erythematosus (SLE). Methods. To estimate disease sensitivity of ANA/8, we studied 25 patients with new SLE and 114 with new and established SLE. To estimate disease specificity, 100 patients with other autoimmune rheumatic diseases were included. We used computerized statistical analysis of the level of 8 ANA in relation to clinical activity determined as Systemic Lupus Activity Measure disease activity scores (DAS). Data were collected retrospectively from the charts of 114 patients with 698 visits and eval- uated by multiple and piece-wise linear regression analysis (PWLRA) and correlation and cluster analyses. Results. The disease sensitivity of the 3 types of SLE profiles identified was 100% for new SLE patients (n = 25) and 87% for mixed SLE patients; the disease specificity was 98%. Autoantibody levels of anti-ssDNA, dsDNA, and Scl-70 were the best individual correlates of general and organ- specific DAS. Twenty-four percent (R 2 ) of the variability in the general DAS was explained by the multiple regression (R = 0.49), with significant contribution made by anti-Scl-70 (ß = 0.39), dsDNA (ß = 0.17), Sm (ß = 0.10), and SSA (ß = 0.08). PWLRA indicated that for 68% of the 698 clinical presentations (average 6/patient), the observed DAS and the predicted DAS from autoantibody levels were both low and clustered; they were partially discrepant for the remaining 32%, which was explained by the relatively high correlation of DAS with prior changes in autoantibody levels (R = 0.6). The changes in DAS and in anti-dsDNA levels were significantly predicted by the multiple regression at one prior visit, with anti-ssDNA as the main contributor. Conclusion. The ANA/8 profile showed ~ 100% sensitivity and ~ 98% specificity for SLE and correlated with contemporary and subsequent changes in DAS and autoantibody levels. Among autoantibodies of this profile, anti-ssDNA (ssDNA) was the most sensitive indicator of SLE and the main contributor to prediction of subsequent changes in DAS. (J Rheumatol 2003;30:1761–9) Key Indexing Terms: SYSTEMIC LUPUS ERYTHEMATOSUS ANTINUCLEAR ANTIBODIES DISEASE ACTIVITY ssDNA Personal, non-commercial use only. The Journal of Rheumatology Copyright © 2003. All rights reserved. www.jrheum.org Downloaded on May 22, 2022 from