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Understanding Your Medical Test: Purpose, Procedure, and Preparation

Published: August 9, 2026Updated: August 16, 2026

The ANA test detects antinuclear antibodies in your blood, helping doctors evaluate for autoimmune conditions.

Quick summary

{"ANA testing helps diagnose autoimmune diseases like lupus and rheumatoid arthritis","Results are reported as a titer (ratio) indicating antibody concentration","A positive result means antibodies were found but does not confirm a specific disease","Follow-up testing is usually needed to determine the exact condition"}

Medically reviewed by WellAlly Editorial TeamLast reviewed August 16, 2026Editorial policy

Key facts at a glance

LOINC
33253-6
Short code
ANA Titr Ser HEp2 subst
Synonyms
ANA Titr Ser HEp2 subst
Category
chemistry
Sample
serum
Container
Red-top tube (SST)
Units
N/A
Fasting
false
Population
adult
Sex
all
Age range
18–65 years
Method
hep-substrate
CPT
86038
Specimen volume
5 mL
Stability
Room temperature: 4h, Refrigerated: 24h, Frozen: 7d
Hemolysis max
500
Lipemia max
1000
Icterus max
500
TAT
4–24 hours
Order
routine

This section explains what the test is, why your doctor may have ordered it, and what information it provides about your overall health and any conditions being evaluated.

The Antinuclear Antibody (ANA) test is a blood test that detects antinuclear antibodies—proteins produced by your immune system that may mistakenly attack the nucleus of your own cells. This test uses Hep-2 cells (human epithelial cells) as a substrate, which is considered the gold standard method because these cells contain many different nuclear antigens, allowing for highly sensitive detection of various antibody patterns.

This section describes how the test is performed, including where it takes place, what you can expect during the procedure, and approximately how long it usually takes to complete.

A healthcare professional will draw a small blood sample from a vein in your arm. The blood is then sent to a laboratory where it is analyzed using indirect immunofluorescence with Hep-2 cells. The test results are reported as a titer (such as 1:40, 1:80, 1:320), with higher titers indicating higher concentrations of antinuclear antibodies.

This section explains how to prepare for the test, including whether you need to fast, which medications to keep taking or pause, and what to discuss with your care team beforehand.

No special preparation is typically required. You can eat and drink normally before the test. However, inform your doctor about any medications you are taking, as certain drugs can affect test results. It is also helpful to tell your doctor about any symptoms you are experiencing.

Clinical interpretation

How abnormal results are interpreted and what conditions they suggest.

A positive ANA test result indicates the presence of antinuclear antibodies in your blood. While this can suggest an autoimmune disease, it does not confirm a specific diagnosis. Many people test positive for ANA but do not have an autoimmune condition. Further testing, including specific antibody panels (such as anti-dsDNA, anti-Sm, anti-RNP), is usually needed to determine the exact condition. Common conditions associated with a positive ANA test include Systemic Lupus Erythematosus (SLE), Sjögren's syndrome, Scleroderma, Rheumatoid arthritis, Polymyositis, and Dermatomyositis.

Frequently asked questions

What does a positive ANA result mean?
A positive ANA result means antinuclear antibodies were detected in your blood. However, this alone does not diagnose a specific disease. Many factors can cause a positive result, including other autoimmune conditions, infections, certain medications, or even in healthy individuals, especially older adults. Your doctor will interpret the result along with your symptoms and may order additional tests to determine the cause.
What is a titer, and what do the numbers mean?
A titer represents the highest dilution of your blood sample in which antibodies can still be detected. For example, a titer of 1:320 means antibodies were detected even when the blood was diluted 320 times. Higher titers (like 1:640 or 1:1280) generally suggest a stronger immune response and may be more clinically significant, though the interpretation depends on the specific pattern and your clinical symptoms.
What are the different ANA patterns?
The Hep-2 cell test can reveal different staining patterns that help identify specific autoimmune conditions. Common patterns include homogeneous (diffuse)—associated with SLE; speckled—associated with SLE, Sjögren's, and scleroderma; nucleolar—associated with scleroderma; and centromere—associated with CREST syndrome. Your doctor uses these patterns along with other tests to guide diagnosis.
Can I have a positive ANA without having a disease?
Yes, it is possible. Up to 10-20% of healthy individuals, particularly older adults, may have a low-positive ANA result. This is called a physiological autoimmunity and usually does not require treatment. Additionally, certain infections, medications (like some blood pressure medications, antibiotics, and anti-seizure drugs), and other conditions can cause a positive ANA without an underlying autoimmune disease.
How long does it take to get results?
Results are typically available within a few days to a week, depending on the laboratory. Since this test requires special expertise and equipment, not all laboratories can perform it, which may affect turnaround time.
  1. 1
    American College of Rheumatology - ANA TestingSource
  2. 2
    Mayo Clinic - ANA TestSource
  3. 3
    Lab Tests Online - ANASource

Click any link to access the full source. PubMed Central (PMC) links provide free full-text access.

This information is for educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment.

Medical Disclaimer

This content is for general informational and educational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the guidance of a qualified healthcare provider with any questions you have about a medical condition, and never disregard professional medical advice or delay seeking it because of something you read here.

If you think you may have a medical emergency, call your local emergency number or go to the nearest emergency department immediately.

Medically reviewed by WellAlly Editorial Team Last reviewed August 16, 2026. · Read our editorial policy