Rationale and Comments
Testing for antinuclear antibody (ANA) and extractable nuclear antigen (ENA) should be avoided in the investigation of widespread pain or fatigue alone. Instead, testing should be performed only in patients suspected to have a diagnosis of a connective tissue disease (e.g., lupus, rheumatoid arthritis). ANA positivity can be as high as 20% in patients with nonrheumatic conditions and healthy individuals. For this reason, proper pretest probability is important, and false-positive results may lead to further unnecessary testing. Repeat testing is also not recommended unless the clinical picture changes significantly.
Sponsoring Organizations
- American Society for Clinical Laboratory Science
- American Society for Clinical Pathology
Sources
Disciplines
References
- Tozzoli R, Bizzaro N, Tonutti E, et al. Guidelines for the laboratory use of autoantibody tests in the diagnosis and monitoring of autoimmune rheumatic diseases. Am J Clin Pathol. 2002;117(2):316-24.
- Solomon DH, Kavanaugh AJ, Schur PH, et al. Evidence-based guidelines for the use of immunologic tests: antinuclear antibody testing. Arthritis Rheum. 2002;47(4):434-44.
- Ferrari R. Evaluation of the Canadian Rheumatology Association Choosing Wisely recommendation concerning anti-nuclear antibody (ANA) testing. Clin Rheumatol. 2015;34(9):1551-1556.