Interpreting ANA, ENA and anti-dsDNA antibodies
How the HEp-2 immunofluorescence ANA is reported (titre and ICAP pattern), how often healthy people test positive, which ENA antibody goes with which disease, the three anti-dsDNA assays and their trade-offs, and when a result should change management.
Tier 2Medical sciences concept
Written with AI assistance and fact-checked against the sources below. For exam study, not clinical decisions. How notes are made
At a glance
- ANA is a screening test. Its value lies in a negative result in someone with low to moderate suspicion: a negative HEp-2 ANA makes SLE and systemic sclerosis very unlikely.
- ENA and anti-dsDNA are the confirmatory tests. They carry the disease specificity, the organ risks and, for dsDNA, the activity signal.
- Order them for a clinical question, such as unexplained inflammatory arthritis, photosensitive rash, serositis, Raynaud with digital changes, cytopenias, proteinuria with haematuria, or unexplained ILD. Fatigue and widespread pain alone give a low pretest probability, and a positive ANA then mostly creates follow-up work.
Loading the rest of the note…
Finished reading?
Sources
- RCPA Manual: antinuclear antibodies, extractable nuclear antigen antibodies and double-stranded DNA antibodiesAU/NZRoyal College of Pathologists of Australasia, online, accessed November 2026
- Therapeutic Guidelines: Rheumatology (systemic lupus erythematosus)AU/NZTherapeutic Guidelines Limited, current online version, accessed November 2026
- Agmon-Levin N et al. International recommendations for the assessment of autoantibodies to cellular antigens referred to as anti-nuclear antibodies. Ann Rheum Dis 2014;73:17-23Annals of the Rheumatic Diseases, 2014
- Damoiseaux J et al. Clinical relevance of HEp-2 indirect immunofluorescent patterns: the International Consensus on ANA patterns (ICAP) perspective. Ann Rheum Dis 2019;78:879-89Annals of the Rheumatic Diseases, 2019
- von Mühlen CA et al. How to report the antinuclear antibodies (anti-cell antibodies) test on HEp-2 cells: guidelines from the ICAP initiative. Immunol Res 2021;69:594-608Immunologic Research, 2021 (current ICAP reporting guidance, checked November 2026)
- International Consensus on ANA Patterns (ICAP): AC-0 to AC-31 nomenclatureICAP, online, accessed November 2026
- Tan EM et al. Range of antinuclear antibodies in 'healthy' individuals. Arthritis Rheum 1997;40:1601-11Arthritis and Rheumatism, 1997
- Aringer M et al. 2019 European League Against Rheumatism/American College of Rheumatology classification criteria for systemic lupus erythematosus. Ann Rheum Dis 2019;78:1151-9EULAR and ACR, 2019 (current)
- Izmirly P et al. Hydroxychloroquine to prevent recurrent congenital heart block in fetuses of anti-SSA/Ro-positive mothers (PATCH). J Am Coll Cardiol 2020;76:292-302Journal of the American College of Cardiology, 2020
- Sammaritano LR et al. 2020 American College of Rheumatology guideline for the management of reproductive health in rheumatic and musculoskeletal diseases. Arthritis Rheumatol 2020;72:529-56American College of Rheumatology, 2020
- van den Hoogen F et al. 2013 classification criteria for systemic sclerosis: an ACR/EULAR collaborative initiative. Ann Rheum Dis 2013;72:1747-55ACR and EULAR, 2013
- Last updated
- 14 November 2026
What changed
- 14 November 2026 Turnstile bot check on sign-in and signed-out feedback