ANA Multiplex, with Reflex to dsDNA Quest

ANA Multiplex, with Reflex to dsDNA - This multiplex immunoassay detects common antinuclear antibodies (ANAs) that are associated with autoimmune diseases. With a reflex to double-stranded DNA (dsDNA), this test may aid in the evaluation of systemic lupus erythematosus (SLE). Because of its limited sensitivity compared to that of ANA immunofluorescence-based tests, multiplex immunoassay is not the preferred assay for ANA testing [1].

This multiplex immunoassay identifies antibodies to dsDNA, chromatin, ribosomal protein, SSA, SSB, Sm, Sm/RNP, RNP, Scl-70, Jo-1, and centromere B. A positive result indicates the presence of at least one of these autoantibodies. These autoantibodies have been associated with several autoimmune diseases, including SLE, systemic sclerosis, mixed connective tissue disease, polymyositis, and Sjogren syndrome. Antibodies to dsDNA are highly specific for SLE and may be detected before flares of the disease [2]. The 2019 European League Against Rheumatism (EULAR)/American College of Rheumatology (ACR) classification criteria include antibodies to dsDNA in their immunology domains and criteria for SLE [3].

A negative result of this test indicates none of the component autoantibodies were detected but does not rule out the autoimmune diseases characterized by other autoantibodies, such as autoimmune hepatitis and primary biliary cholangitis. The classic ANA immunofluorescence assay on human epithelial type 2 cells, an assay that can detect up to 150 antibodies, is considered by the ACR as the current gold standard for ANA testing [1].

The results of this test should be interpreted in the context of pertinent clinical and family history and physical examination findings.