Antinuclear Antibody (ANA) Screen Test
The antinuclear antibody (ANA) screen detects autoantibodies against nuclear components and is the principal first-line test for suspected systemic autoimmune disease, particularly systemic lupus erythematosus, for which it is highly sensitive.
1
Biomarkers
Blood (serum)
Sample
2–4 business days
Turnaround
No
Fasting
What is the ANA Screen test?
The ANA Screen detects antinuclear antibodies, the principal first-line marker for suspected systemic autoimmune (connective tissue) disease. It is ordered when the clinical picture — such as arthralgia, rash, photosensitivity, serositis, or multisystem symptoms — raises the possibility of a condition like systemic lupus erythematosus. Within autoimmune assessment, the ANA screen is a highly sensitive but non-specific gateway test. It is especially useful for its high negative predictive value in SLE: a negative result makes SLE unlikely. A positive result, however, must be interpreted against the titre, the immunofluorescence pattern, and the clinical context, because low-titre positives are common in healthy people, increase with age, and occur in infections and other conditions. A meaningful positive is followed by specific autoantibody testing directed by the pattern and titre to characterise the underlying disease. Indirect immunofluorescence on HEp-2 cells is the reference method; immunoassay-based screens are also used and may need confirmation. The ANA is interpreted with inflammatory markers, complement, and the specific antibody profile rather than in isolation.
What does the ANA Screen test measure?
Antinuclear antibodies are autoantibodies directed against components of the cell nucleus, including DNA, histones, and various nuclear proteins. They arise from a loss of immune self-tolerance and are a hallmark of systemic autoimmune (connective tissue) diseases, though they also occur in healthy individuals — increasingly with age — and in infections, other autoimmune conditions, and with certain drugs. Indirect immunofluorescence on HEp-2 cells is the reference method, yielding both a titre and a staining pattern that can suggest particular antibody specificities.
The ANA screen is the principal first-line test for suspected systemic autoimmune disease, particularly systemic lupus erythematosus, for which it is highly sensitive. Because it is not specific and a low-titre positive is common in healthy people, a positive result is interpreted in the clinical context and followed by specific antibody testing (such as anti-dsDNA, anti-Sm, anti-Ro/La, anti-centromere, anti-Scl-70) guided by the titre and pattern. A negative ANA makes SLE unlikely but does not exclude all autoimmune disease.
Why is the ANA Screen test ordered?
- Investigation of suspected systemic lupus erythematosus or other connective tissue disease with suggestive multisystem features
- Evaluation of unexplained arthralgia or arthritis with features suggesting an autoimmune rather than degenerative cause
- Assessment of suspected Sjögren's syndrome, systemic sclerosis, dermatomyositis, or mixed connective tissue disease, followed by pattern-directed specific testing
- Workup of unexplained multisystem symptoms — rash, photosensitivity, serositis, cytopenias, or renal involvement — where autoimmunity is considered
- Investigation of suspected drug-induced lupus, interpreted with the medication history and anti-histone antibodies
- Evaluation of Raynaud's phenomenon with features suggesting an underlying connective tissue disease
- Assessment where a highly sensitive screen is wanted to help exclude SLE, given the strong negative predictive value
Sample collection and turnaround
Sample type
Blood (serum)
Fasting required
No
Collection method
Venipuncture at patient service centre
Turnaround
2–4 business days
Collection notes
No special preparation required. Document relevant medications (e.g. hydralazine, procainamide), recent infection, and the clinical features prompting testing, as these guide interpretation of a positive result. A positive screen is typically followed by pattern- and titre-directed specific autoantibody testing.
Specimen requirements
Minimum 0.5 mL serum. Separate serum from cells per Access Medical Laboratories protocol. Specimen stable refrigerated; follow Access Medical Laboratories transport guidelines.
What can affect ANA Screen results?
Low-titre ANA positivity is common in healthy individuals and increases with age and in women, so a low-titre positive without clinical features is often not significant.
Indirect immunofluorescence on HEp-2 cells is the reference method and provides titre and pattern, while immunoassay screens can differ in sensitivity and specificity and may miss or over-call certain patterns; method affects interpretation.
Acute and chronic infections and other inflammatory states can transiently induce ANA positivity that does not reflect a connective tissue disease.
Drugs such as hydralazine, procainamide, and some others can induce ANA and drug-induced lupus, typically with anti-histone antibodies. Medication history should be documented.
ANA positivity occurs in autoimmune thyroid and liver disease and other conditions, so a positive result is not specific to connective tissue disease and requires clinical correlation.
A positive ANA at low titre frequently occurs without any autoimmune disease, so the titre and pattern, not merely positivity, guide whether the result is clinically meaningful.
What do ANA Screen results mean?
Elevated
A positive ANA, particularly at higher titre (e.g. 1:160 or above) with a clinically relevant pattern, supports a systemic autoimmune disease and prompts specific autoantibody testing guided by the pattern — for example anti-dsDNA and anti-Sm for SLE, anti-centromere or anti-Scl-70 for systemic sclerosis, anti-Ro/La for Sjögren's. The result is interpreted with the clinical picture.
Normal
A negative ANA makes systemic lupus erythematosus unlikely given the test's high sensitivity, though it does not exclude all autoimmune disease. Where clinical suspicion remains high, method limitations and specific antibodies (some of which can occur with a negative screen) should be considered.
Reduced
Not applicable — ANA is reported as negative or positive with a titre rather than as a graded low value.
Note: The ANA screen is sensitive but non-specific: low-titre positives are common in healthy people and rise with age, and positivity occurs in infections, other autoimmune conditions, and with certain drugs. It must be interpreted with the titre, pattern, and clinical context, and a meaningful positive is followed by pattern-directed specific antibody testing. Method (immunofluorescence vs immunoassay) affects sensitivity and reporting, and a negative result does not exclude all connective tissue disease.
Frequently asked questions
It detects antinuclear antibodies, autoantibodies against components of the cell nucleus. It is the principal first-line test for suspected systemic autoimmune (connective tissue) disease, particularly systemic lupus erythematosus.
How to access the ANA Screen test
The ANA Screen reference page is free and open to all practitioners. Create a free practitioner account to see pricing, save tests to your list, and generate requisition forms. Verification takes 1–2 business days.
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Published: June 2, 2026
Last reviewed: June 2, 2026
- Aringer M, et al. 2019 EULAR/ACR Classification Criteria for Systemic Lupus Erythematosus. Arthritis Rheumatol. (2019)
- 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)
- Kavanaugh A, et al. Guidelines for clinical use of the antinuclear antibody test and tests for specific autoantibodies to nuclear antigens. Arch Pathol Lab Med. (2000)
- Solomon DH, et al. Evidence-based guidelines for the use of immunologic tests: antinuclear antibody testing. Arthritis Rheum. (2002)
This content is for licensed healthcare practitioners only and does not constitute medical advice. Clinical decisions should be based on the full clinical picture and not on any single test result.