Evaluation of Two Commercial Immunoassays Used to Screen Patients for Systemic Lupus Erythematosus

Abstract

Diagnosing systemic lupus erythematosus (SLE) can be challenging as laboratory screening methods, although sensitive, lack specificity. The poor specificity of autoimmune testing produces more false positive results than true positive results. False positive results can cause stress to patients without autoimmune disease and require unnecessary rheumatology consultation to rule out disease. Our objective was to evaluate two screening assays to reduce the number of false positives while maintaining high sensitivity. In this study, we evaluated two immunoassays, the AtheNA Multi-Lyte II ANA System and QUANTA Lite ANA ELISA, to screen patients for SLE. All positive screening results were compared to immunoflourescent ANA testing using theHEp-2000 ANA System. A chart review was performed on all patients tested to determine clinical diagnosis of SLE. The QuantaLite ANA ELISA produced significantly more false positive results than the AtheNA Multi-Lyte II Test System when screening for SLE in our patient population.